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Earth Sciences, Environmental Sciences; Flint Creek; mercury; water quality; fish; soil; sediment; organic carbon; methylmercury
Online: 15 August 2018 (11:49:50 CEST)
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Water, soil/sediment, and 36 fish samples were collected at three major sites along Flint Creek in 2015-2016 and analyzed for total organic carbon (TOC), dissolved organic carbon (DOC), total mercury (tHg), and other water quality indicators. This study was a follow-up to a 2012 study that revealed elevated tHg levels in fish, resulting in a public health advisory. This study revealed tHg concentrations in water below the detection limit (0.0002 ppm); while, tHG in soil/sediment ranged from < 0.0133 ppm to 0.0682 ppm dry weight. No temporal trends existed, but tHG tended to increase with TOC. Mercury levels in sediment were below the threshold effects level suggested as a preliminary screening level by the National Oceanic and Atmospheric Administration (acute = 1.4, chronic = 0.77 ppb). In summary, tHg levels were low; posing little risk to drinking water. Soil/sediment levels were generally higher and could pose risk to aquatic species.
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Earth Sciences, Environmental Sciences; mHM, remote sensing, spatial pattern, sensitivity analysis, GLUE, actual evapotranspiration
Online: 11 August 2018 (18:36:29 CEST)
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Hydrologic models are conventionally constrained and evaluated using point measurements of streamflow, which represents an aggregated catchment measure. As a consequence of this single objective focus, model parametrization and model parameter sensitivity are typically not reflecting other aspects of catchment behavior. Specifically for distributed models, the spatial pattern aspect is often overlooked. Our paper examines the utility of multiple performance measures in a spatial sensitivity analysis framework to determine the key parameters governing the spatial variability of predicted actual evapotranspiration (AET). Latin hypercube one-at-a-time (LHS-OAT) sampling strategy with multiple initial parameter sets was applied using the mesoscale hydrologic model (mHM) and a total of 17 model parameters were identified as sensitive. The results indicate different parameter sensitivities for different performance measures focusing on temporal hydrograph dynamics and spatial variability of actual evapotranspiration. While spatial patterns were found to be sensitive to vegetation parameters, streamflow dynamics were sensitive to pedo-transfer function (PTF) parameters. Above all, our results show that behavioral model definition based only on streamflow metrics in the generalized likelihood uncertainty estimation (GLUE) type methods require reformulation by incorporating spatial patterns into the definition of threshold values to reveal robust hydrologic behavior in the analysis.
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Earth Sciences, Environmental Sciences; morphological indices; urban climate; planning process
Online: 9 August 2018 (06:21:33 CEST)
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The purpose of this article is to analyze urban form through the mapping of morphological indices, namely impervious surface fraction, building density, verticality, height/width ratio, roughness length, and porosity, to support urban planning in the city of João Pessoa, PB, in northeastern Brazil. The application of this study identifies and calculates such significant indices for the city's urban space from a Geographic Information System (GIS) model. The spatial indices play notable roles in climate at different scales, developing guidelines to maximize environmental quality, promote improvements to thermal comfort, minimize the urban heat island in the city of João Pessoa, and provide relevant data (considering microclimate aspects), guiding decisions related to the planning process.
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Earth Sciences, Environmental Sciences; persistent pollutants; risk assessment; arctic; glacial melt; climate change;human health; alaska; alpine glacier; Alaska Range
Online: 9 August 2018 (00:40:50 CEST)
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To assess the presence of organochlorine pollutants (OCP) in Alaskan sub-Arctic latitudes, we analyzed ice core and meltwater samples from Jarvis Glacier, a polythermal glacier in Interior Alaska. Jarvis Glacier is receding as atmospheric warming continues throughout the region, increasing opportunity for OCP transport both englacially and into the proglacial watershed. Across all meltwater and ice core samples we identify the pesticides DDT, DDE and DDD, α- HCH and ϒ-HCH. OCP concentrations in ice core samples were highest at the 7-14 m depth (0.51 ng/L of DDT) and decreased gradually approaching the bedrock at 79m. Meltwater concentrations from the proglacial creek slightly exceeded concentrations found in the ice core, potentially indicating aggregate OCP glacial loss, with peak OCP concentration (1.12 ng/L of DDD) taken in July and potentially associated to peak melt. Ongoing use of DDT to fight Malaria in Asia, and the extended atmospheric range of HCH may account for concentrations in near-surface ice, correlating with use and atmospheric transport. The opportunity for biota bioaccumulation of OCPs, or human uptake of OCPs from glacial meltwater, may increase as glacial melt continues.
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Earth Sciences, Environmental Sciences; ammonia nitrogen; bentonite; COD; RSM; sawdust; SBR
Online: 6 August 2018 (09:08:31 CEST)
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Water pollutants removal by biomass adsorbent has been considered innovative and cost effective, thus commendable for application in industrial applications. However, certain important aspects have been overlooked by researchers, namely the efficiency in the operation time and pollutant removal. In this research, landfill leachate samples with organic components were treated using bentonite-enriched with sawdust augmented (SBR) process. By modifying the pH, the sawdust samples were categorized into three: the acidic, the alkaline, and the neutral. To bentonite samples, the pH-adjusted sawdust was added at 10%, 20%, and 30% amounts by mass respectively. At the optimum aeration rate of 7.5 L/min and contact period of 22 h, the treatment achieved 99.28% and 95.41% removal of COD and NH3-N with bentonite respectively. For both pollutants, in the presence of sawdust, the removal reduced by about 17% with contact period reduced to 2 h which was a considerable achievement.
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Earth Sciences, Environmental Sciences; mine waste; lead; zinc; cadmium; microbial role; sulfur-reducing bacteria
Online: 4 August 2018 (11:07:24 CEST)
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Milling and mining metal ores are major sources of heavy metal contamination. The Spring River and its tributaries in southeast Kansas are contaminated with Pb, Zn, and Cd as a result of 120 years of mining activities. Trace metal transformations and cycling in mine waste materials greatly influence their mobility and toxicity and affect plant productivity and human health. It has been hypothesized that under reduced conditions in sulfate-rich environments, these metals can be transformed into their sulfide forms, thus limiting mobility and toxicity. We studied biogeochemical transformations of Pb, Zn and Cd in flooded subsurface mine waste materials, natural or treated with organic carbon (OC) and/or sulfur (S), by combining advanced microbiological and X-ray spectroscopic techniques to determine the effects of treatments on the microbial community structure and identify the dominant functional genes involved in the biogeochemical transformations, especially metal sulfide formation over time. Samples collected from medium-, and long-term submerged columns were used for microarray analysis via functional gene array (GeoChip 4.2). The total number of detected gene abundance decreased under long-term submergence, but major functional genes abundance was enhanced with OC plus S treatment. The microbial community exhibited a substantial change in structure in response to OC and S addition. Sulfur-reducing bacteria genes dsrA/B were identified as key players in metal sulfide formation via dissimilatory sulfate reduction. Uniqueness of this study is that microbial analyses presented here in details are in agreements with molecular-scale synchrotron-based X-ray data supporting that OC-plus-S treatment would be a promising strategy for reducing metal toxicity in mine waste materials.
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Earth Sciences, Environmental Sciences; Artificial restoration; ecological restoration; coal mining subsidence; semi–arid; soil microbial community
Online: 3 August 2018 (15:48:23 CEST)
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Increased attention has been paid to the influence of coal mining subsidence on ecological environment. Restoration of ecosystem in damaged mining area is critical for restoring disturbed environment. The comparing of plant communities and microbial communities in the artificial restoration and natural restoration areas provides an effective method for evaluating the restoration effects. However, such studies are limited in coal mining subsidence restoration areas. Subsidence area in Shendong mining area, located in the semi-arid region of Western China, was restored from 2003 with 5 ecological restoration plant species. In July 2017, the comparison and analysis of plant and microbial communities were conducted at the artificial restoration areas (AR) and the natural remediation areas (NR). The results showed that the artificial ecological restoration in Shendong mining area has achieved some success, but it has not recovered to a similar ecosystem before the destruction. A higher plant species, coverage and bacterial community diversity were observed in AR. However, these features have lower similarity compared with those in NR sites. Potential soil factors, such as pH, moisture content, total carbon content, organic matter, nitrogen and bulk density, have a greater impact on soil bacterial community structure and diversity. In the ecological restoration of the mining area, attention should be paid to the restoration of soil properties in the mining area. This study can provide theoretical guidance for more scientific ecological restoration in the damaged mining area.
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Earth Sciences, Environmental Sciences; groundwater; Haiti; filtration; water treatment; developing country; point of use treatment; household treatment
Online: 3 August 2018 (04:03:22 CEST)
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Water resources, especially safe, potable water, are limited for many Haitians. In areas where shallow groundwater is available, many household water needs such as laundry, bathing, and cooking are supplied by hand-dug wells. In order to better understand the water quality and prevalence of these household wells, 35 hand-dug wells were surveyed and sampled near the Hôpital Albert Schweitzer (HAS) in Deschapelles, Haiti. Water samples were collected and tested for fecal coliform and E. coli using the IDEXX Colilert-18 method. Of the samples collected, 89 percent were determined unsafe to use as a drinking water source based on the World Health Organization standard of 1.0 colony-forming unit (cfu) Escherichia Coli (E. coli) per 100 mL. 66 percent of the wells exceeded recreational/body contact standards for the state of Michigan (130 cfu/100 mL). Some of these wells were deemed suitable for conversion to a new well type called In-Situ Filtration (ISF) wells. ISF wells are installed with an internal sand filter pack, PVC casing, pump, and cap which seals the well from surface contamination and provides additional water treatment as water is pumped. Previous ISF installations have reduced E. coli to safe drinking water levels within 90 days.
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Earth Sciences, Environmental Sciences; Landsat, analysis ready data, collection 1
Online: 1 August 2018 (20:03:52 CEST)
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Data that have been processed to allow analysis with a minimum of additional user effort are often referred to as Analysis Ready Data (ARD). The ability to perform large scale Landsat analysis relies on the ability to access observations that are geometrically and radiometrically consistent, and have had non-target features (clouds) and poor quality observations flagged so that they can be excluded. The United States Geological Survey (USGS) has processed all of the Landsat 4 and 5 Thematic Mapper (TM), Landsat 7 Enhanced Thematic Mapper Plus (ETM+), Landsat 8 Operational Land Imager (OLI) and Thermal Infrared Sensor (TIRS) archive over the conterminous United States (CONUS), Alaska, and Hawaii, into Landsat ARD. The ARD are available to significantly reduce the burden of pre-processing on users of Landsat data. Provision of pre-prepared ARD is intended to make it easier for users to produce Landsat-based maps of land cover and land-cover change and other derived geophysical and biophysical products. The ARD are provided as tiled, georegistered, top of atmosphere and atmospherically corrected products defined in a common equal area projection, accompanied by spatially explicit quality assessment information, and
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Earth Sciences, Environmental Sciences; bed load transport; shear Reynolds number; mixed-size bed material; complex morphodynamics
Online: 1 August 2018 (19:56:03 CEST)
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The aim of this study is to introduce a novel method which can separate sand or gravel dominated bed load transport in rivers with mixed-size bed material. In engineering practice, the Shields-Parker diagram could be used for such purposes, however, the method has certain applicability limits, due to the fact that it is based on uniform bed material and provides information rather on river-scale, instead of reach or local scale. When dealing with large rivers with complex hydrodynamics and morphodynamics the bed load transport modes can also indicate strong variation even locally, which requires a more suitable approach to estimate the locally unique behavior of the sediment transport. Here, we suggest that the decision criteria utilizes the shear Reynolds number (Re*). The method was verified against field and laboratory measurement data, both performed at non-uniform bed material compositions. The comparative assessment of the results show that the shear Reynolds number based method operates more reliably than the Shields-Parker diagram and it is expected to predict the sand or gravel transport domination with a < 5% uncertainty. The introduced results can greatly contribute to the improvement of numerical sediment transport modeling as well as to the field implementation of bed load transport measurements.
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Earth Sciences, Environmental Sciences; flood mapping; Multispectral; SAR; free satellite data; Ebro basin; Po basin
Online: 31 July 2018 (12:45:03 CEST)
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Satellite remote sensing is a powerful tool to map flooded areas. In the last years, the availability of free satellite data sensibly increased in terms of type and frequency, allowing producing flood maps at low cost around the World. In this work, we propose a semi-automatic method for flood mapping, based only on free satellite images and open-source software. As case studies, we selected three flood events recently occurred in Spain and Italy. Multispectral satellite data acquired by MODIS, Proba-V, Landsat, Sentinel-2 and SAR data collected by Sentinel-1 were used to detect flooded areas using different methodologies (e.g., MNDWI; SAR backscattering variation; Supervised classification). Then, we improved and manually refined the automatic mapping using free ancillary data like DEM based water depth model and available ground truth data. For the areas affected by major floods, we also validated and compared the produced flood maps with official maps made by river authorities. We calculated flood detection performance (flood ratio) for the different datasets we used. The results show that it is necessary to take into account different factors for the choice of best satellite data, among these, the time of satellite pass with respect to the flood peak is the most important one. SAR data showed good results only for co-flood acquisitions, whereas multispectral images allowed detecting flooded areas also with the post-flood acquisition. With the support of ancillary data, it was possible to produce reliable geomorphological based flood maps in the study areas.
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Earth Sciences, Environmental Sciences; backscattering; L-band; SAR polarimetry; microwave; Chapman-Richards model; tropical forest
Online: 31 July 2018 (05:02:29 CEST)
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Secondary forests (SF) are important carbon sinks, removing CO2 from the atmosphere through the photosynthesis process and storing photosynthates in their aboveground live biomass (AGB). This process occurring at large-scales partially counteracts C emissions from land-use change, playing, hence, an important role in the global carbon cycle. The absorption rates of carbon in these forests depend on forest physiology, controlled by environmental and climatic conditions as well as on the past land use, which is rarely considered for retrieving AGB from remotely sensed data. In this context, the main goal of this study is to evaluate the potential of full polarimetric ALOS-2 PALSAR-2 data for estimating AGB by taking into account the past-land use of SF areas in the Brazilian Amazon. We surveyed a chronosequence of 42 SF plots (20 ha) near the Tapajós National Forest in Pará state to quantifying AGB growth rates. We explored the full polarimetric data testing three regression models including non-linear (NL), multiple linear regressions models (MLR), and the semi-empirical extended water cloud model (EWCM). The results showed that the intensity of previous use has affected the structure of SF by reducing the AGB accumulation and being noticeable by several polarimetric attributes. The combination of multiple prediction variables with MLR improved the AGB estimation by 70% comparing amongst other models (R² adj. = 0.51; RMSE = 13.2 Mg ha-1) bias = 2.1 ± 37.9 Mg ha-1. The error propagation of the MLR model was estimated to be 15%.
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Earth Sciences, Environmental Sciences; recharge area; karst aquifers; stable isotope, environmental tracer
Online: 27 July 2018 (14:30:08 CEST)
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Water resources management is one of the most important challenges worldwide because water represents a vital resource for sustaining life and environment. In the aim of sustainable groundwater management, the identification of aquifer recharge areas is a useful tool for water resources protection. In a well-developed karst aquifer, environmental isotopes provide support for identifying aquifer recharge areas, residence time and interconnections between aquifer systems. This study deals the use of environmental isotopes to identify the main recharge area of a karst aquifer in the Upper Valley of Aniene River (Central Italy). The analysis of 18O/16O and 2H/H values and their spatial distribution in the aquifer, make it possible to trace back groundwater recharge areas based on average isotope elevations. The Inverse Hydrogeological Balance Method was used to validate spring recharge elevations obtained by the use of stable isotopes. Areas impacted by direct and rapid rainfall recharge into the study area were delineated, showing groundwater flowpaths from the boundaries to the core of the aquifer. The results of this study demonstrate the contribution that spatial and temporal isotope changes can provide to the identification of groundwater flowpaths in a karst basin, taking into account the hydrogeological setting
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Earth Sciences, Environmental Sciences; sea; remote sensing; oil pollution
Online: 27 July 2018 (06:19:37 CEST)
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Oil spills are adverse events that may be very harmful to ecosystems and food chain. In particular, large sea oil spills are very dramatic occurrence often affecting sea and coastal areas. Therefore the sustainability of oil rig infrastructures and oil transportation via oil tankers are linked to law enforcement based on proper monitoring techniques which are also fundamental to mitigate the impact of such pollution. Within this context, in this study a meaningful showcase is analyzed using remotely sensed measurements collected by the Synthetic Aperture Radar (SAR) operated by the COSMO-SkyMed (CSK) constellation. The showcase presented refers to the Deepwater Horizon (DWH) oil incident that occurred in the Gulf of Mexico in 2010. It is one of the world's largest incidental oil pollution event that affected a sea area larger than 10,000 km2. In this study we exploit, for the first time, dual co-polarization SAR data collected by the Italian CSK X-band SAR constellation showing the key benefits of HH-VV SAR measurements in observing such a huge oil pollution event, especially in terms of the very dense revisit time offered by the CSK constellation.
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Earth Sciences, Environmental Sciences; Bronze Age settlement; modern soil; micromorphology; chemical properties; gypsum; anthropogenic impact
Online: 24 July 2018 (12:00:13 CEST)
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In some cases, the human impact on ancient landscapes has been so profound that local soils still remain significantly affected even after hundreds and thousands of years after ending impact. We studied the Late Bronze Age Muradymovo settlement located in Urals, Russia, aiming to estimate the consequences of the ancient people activity for environment. Despite the present humid climate, the modern soils inside the cultural layer of the study site contain more than 27% of gypsum at a depth of just 10 cm from the surface, and a microrelief of the study site is typical of a gypsum desert. The nearby background Chernozems are gypsum-free to a depth of 2 meters. According to the archaeological data, the ancient people belonged to the ‘Srubno-Alakul’ archaeological culture (1750–1350 yrs BC cal) and had a tradition of building their houses from gypsum rocks. At the present time, this area is still unsuitable for human settlement. The properties of modern soils inside the cultural layer of the study site are directly affected by the Late Bronze Age human activities. It has been identified on soil morphology, micromorphology and chemical properties of soils developed inside the cultural layer of the settlement.
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Earth Sciences, Environmental Sciences; groundwater; sustainability assessment; small islands; Caribbean islands; sustainability assessment indicators; water management
Online: 24 July 2018 (08:12:19 CEST)
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Groundwater is an important resource for many countries and its scarcity is a major concern in small territories, especially in the islands where the constant extraction is creating a high risk of public calamity. This issue has been increasing because of the anthropogenic activities and the climate change and it has called the attention of scientists and stakeholders in order to assess the sustainability of the water management system, and therefore, to establish strategies for a more sustainable water use. San Andres island was taking as case study and a description of the water balance was carried out in order to understand the management system. Then, a water system sustainability assessment was performed with indicators such as water security, water quality, drinking water, sanitation, infrastructure, climate robustness, biodiversity, attractiveness, and governance, according to the City Blueprint Methodology. The result for the 24 evaluated indicators was a score of 3.2, whose interpretation is “an unsustainable water management”. The qualitative assessment was the base to propose water security, water quality, and governance strategies to improve the water management in the island. The assessment and its discussions are relevant for the water management in small islands across the world whose economy is based on the tourism and whose water security is at a high risk.
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Earth Sciences, Environmental Sciences; physico-chemical characteristics; biochar; BET surface area; SEM; total carbon; CEC; FTIR; feedstock
Online: 22 July 2018 (11:38:11 CEST)
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This study compares the physico-chemical characteristics of three different types of biochar produced from biomass residues in Vietnam as a basis for optimising their application in water purification and soil fertilisation. Wood biochar (WBC), rice husk biochar (RBC), and bamboo biochar (BBC) were produced under limited oxygen conditions using equipment available locally in Vietnam, known as a Top-Lid Updraft Drum (TLUD). The resulting biochars were characterised using a suite of state-of-the-art methods to understand their morphology, surface chemistry and cation exchange capacity. Surface areas (measured by BET) for WBC and BBC were 479.34 m2/g and 434.53 m2/g, respectively, significantly higher than that of RBC which was only 3.29 m2/g. The morphology as shown in SEM images corresponds with the BET surface area, showing a smooth surface for RBC, a hollow surface for BBC, and a rough surface for WBC. All three biochars produced alkaline, with pH values around 10, and all have high carbon contents (47.95 - 82.1 %). Cation exchange capacity (CEC) was significantly different (p<0.05) among the biochars, being 26.70 cmol/kg for RBC, 20.7 cmol/kg for BBC, and 13.53 cmol/kg for WBC, which relates to the cations (Ca, Mg, K) and functional groups with negative charge (carboxyl, hydroxyl) present on the biochar surfaces. The highest contents of Ca, Mg and K in rice husk BC may explain its highest CEC values. Thus, although the biochars were produced by the same method, the various feedstocks lead to quite different physico-chemical properties. Ongoing work is linking these physico-chemical properties to the biochar efficiencies in terms of nitrate and ammonia capture capacities for use as fertilisers, and for adsorption of heavy metals (Zn, Cu) or water filtration, in order to design optimal biochar properties for specific applications.
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Earth Sciences, Environmental Sciences; stormwater; monitoring; gross pollutant generation rates; suspended solids; nitrogen; phosphorus; heavy metals
Online: 18 July 2018 (09:07:46 CEST)
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Urban stormwater runoff from a medium-density residential development in southeast Queensland has been monitored in the field since November 2013. A treatment train installed on the site includes rainwater tanks collecting roofwater, 200-micron mesh baskets installed in grated gully pits and two 850 mm high media filtration cartridges installed in an underground 4 m3 vault. A monitoring protocol developed by research partners, Queensland University of Technology (QUT), guided the monitoring process over a 4.5-year period. Heavy metals were included in the list of analytes during the monitoring period as the catchment is within 1 km of the environmentally-sensitive Moreton Bay, Queensland. Removal efficiencies observed at this site for the regulated pollutants; total suspended solids (TSS), total phosphorus (TP) and total nitrogen (TN) for the pit baskets were 61%, 28% and 45% respectively. The cartridge filters removed 78% TSS, 59% TP, 42% TN, 40% total copper and 51% total zinc. As the measured influent concentrations to the cartridge filters were low when compared to industry guidelines, the dataset was merged with international field results for TSS (n=39) and TP (n=32) but truncated within anticipated guideline levels. The combined dataset for the media filter demonstrates performance at 89% TSS, 66% TP and 42% TN. The total gross pollutant generation rate from the medium-density residential catchment was observed to be 0.24 m3/Ha/year, with a corresponding air-dried mass of 142.5 kg/Ha/year. Less than 2% of the gross pollutant mass was anthropogenic. The findings of this research suggest that the treatment train, and in particular the media filter, holds promise for the removal of total copper and total zinc, in addition to TSS, TP and TN, from urban stormwater runoff. Based on a maximum, low risk trigger TN concentration of 1.5 mg/L, the field test data from 4.5 years of operation and standard maintenance, suggests a 5.5-year replacement interval for the media filters.
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Earth Sciences, Environmental Sciences; adaptation; complex adaptative systems; ecosystem services; governance; resilience; sustainability; transdisciplinary
Online: 17 July 2018 (10:06:22 CEST)
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In the last decade, probably in response to global changes and environmental crisis, the use of the term “social-ecological system” (SES) in the scientific literature has been growing. This is certainly a sign of the recognition of the need and importance of transdisciplinary research. Here, we explore whether the use of the term is a buzzword, or it actually represents a key concept toward the integration of social and ecological research. We compiled a data base of publications (N = 1289) that mentioned SES in title, keywords and abstract. Subsequently, we analyzed: authors affiliations, type of work (conceptual, empirical, review), study site, prevailing human use, temporal and spatial scales of analysis, kind of variables analyzed (socioeconomic, biophysical), and the method/s used to integrate them. We detected four time spans in the use of the term (1975–1997, 1998–2006, 2007–2012, 2013–2016). Our results suggest that SES is a widely invoked concept to study the interface between social and ecological systems. Most works show some common elements such as the analysis of resilience, ecosystem services, sustainability, governance and adaptive management. However, the majority of studies does not study SES as a whole, integrating both social and ecological variables and their feedback loops. We consider that SES is still a concept in construction in order to build a necessary framework to integrate social and ecological sciences. For a robust evolution we recommend to focus on 1. a conscious, discussed and agreed effort of scientists to conduct transdisciplinary research needed to study SES; 2. developing methodological tools for the true integration of social and ecological data.
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Earth Sciences, Environmental Sciences; climate change; gis; geostatistic; raster math
Online: 16 July 2018 (12:26:24 CEST)
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The province of Macerata, Italy, is a topographically complex region which has been little studied in terms of its temperature and precipitation climatology. Temperature data from 81 weather stations and precipitation data from 55 rain gauges were obtained, and, following quality control procedures, were investigated on the basis of 3 standard periods: 1931-1960, 1961-1990 and 1991-2014. Spatial and temporal variations in precipitation and temperature were analysed on the basis of six topographic variable (altitude, distance from the sea, latitude, distance from the closest river, aspect, and distance from the crest line). Of these, the relationship with altitude showed the strongest correlation. Use of GIS software allowed investigation of the most accurate way to present interpolations of these data and assessment of the differences between the 3 investigated periods. The results of the analyses permit a thorough evaluation of climate change spatially over the last 60 years. Generally, the amount of precipitation is diminished while the temperature is increased across the whole study area, but with significant variations within it. Temperature increased by 2 to 3°C in the central part of the study area, while near the coast and in the mountains the change is between about 0 and 1°C, with small decreases focused in the Appennine and foothill belt (-1 to 0°C). For precipitation, the decrease is fairly uniform across the study area (between about 0-200 mm), but with some isolated areas of strong increase (200-300 mm) and only few parts of territory in which there is an increase of 0-200 mm, mainly in the southern part of the coast, to the south-west and inland immediately behind the coast. The monthly temperature trend is characterized by a constant growth, while for precipitation there is a strong decrease in the amount measured in January, February and October (between 25 and 35 mm on average).
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Earth Sciences, Environmental Sciences; ecological footprint; biocapacity; resource consumption; grazing land; carbon emission; renewable energy
Online: 9 July 2018 (14:05:23 CEST)
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Urbanization and industrialization processes in Mongolia have been significant and rapid for the last half-century. During this period, changes in political and economic systems, growth in the population, and the occasional harsh climate conditions were subject to fluctuations in the natural resource usage. The total Ecological Footprint (EF) in Mongolia has increased from 6.8 million global hectares (gha) in 1961 to 14.6 million gha in 2012. However, Biocapacity (BC) has decreased from 50.6 million gha in 1961 to 39.0 million gha in 2012. The study shows that grazing land Footprint and carbon uptake land Footprint are the two major contributors of the recent intensified use of biological resources. To ensure stable economic development and sustainable use of natural resources, environmental planning is required to consider both the population’s pressure on the environment and the ecosystem’s regeneration capacity, simultaneously. We have proposed a few possible strategies for sustainable utilization of grazing land Footprint and carbon Footprint. For grazing land Footprint, efficient management of both herding practice and number of animals should be considered. In case of carbon Footprint, it is estimated that with the improved combustion efficiencies of coal-based power plants and the maximum use of renewable energy, carbon dioxide (CO2) emissions in Mongolia can be reduced up to 30% compared to the base line business as usual case in 2030.
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Earth Sciences, Environmental Sciences; cultural heritage; preventative conservation; climate change; mitigation; adaptation; climate modelling
Online: 4 July 2018 (10:36:51 CEST)
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There is a range of local weather and climate-related factors that contribute to the degradation of cultural heritage buildings, structures and sites over time. Some of these factors are influenced by changes in climate and some of these changes manifest themselves though a speeding up of the rate of degradation. It is the intention of this paper to review this situation with special reference to the Nordic Countries, where typical trends resulting from climate change are shorter winters and increased precipitation all year round. An attempt is made to initially draw up a classification of materials and structures relevant to cultural heritage that are affected, with a proposed numeric scale for the urgency to act. The intention is to provide information on where best to concentrate cultural heritage site preservation resources in the future.
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Earth Sciences, Environmental Sciences; cover crop; spontaneous vegetation; vineyard; topsoil water content; soil erosion; runoff coefficient; sediment trap; temporal stability; Mediterranean region
Online: 3 July 2018 (11:20:06 CEST)
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Soil erosion seriously affects vineyards. In this study, the influence of two plant covers on soil moisture and the effect of different physiographic conditions on runoff and sediment yields were evaluated in a rainfed vineyard formed by four fields (NE Spain) during 15 months. One field had spontaneous vegetation as plant cover and three fields had a cover crop of common sainfoin. The vineyards’ rows were dry and stable, whereas the inter-row areas were wet although very variable, and the corridors were wet and very stable. Soil moisture in the inter-row areas with Common sainfoin was much higher than in the rows (62% - 70%) whereas this difference was lower with spontaneous vegetation (40%). Two runoff and sediment traps (STs) were installed in two ephemeral gullies, and 26 time-integrated surveys (TIS) done. The mean and maximum runoff yields were 9.8 and 30.7 l TIS–1 in ST2 and 13.5 and 30.2 l TIS–1 in ST3. The mean turbidity was 333 and 19 g l–1, and the maximum sediment yields were 41,260 and 2,778 g TIS–1 in ST2 and ST3. Changes in the canopy covers (grapevines and plant covers) and rainfall parameters explained the runoff and sediment dynamics.
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Earth Sciences, Environmental Sciences; allophane; adsorption; precipitation; interface processes; environment; heavy metals; nano-structure; short-range order aluminosilicate; wastewater treatment; aqueous geochemistry
Online: 28 June 2018 (15:39:12 CEST)
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The capacity and the mechanism of the adsorption of aqueous barium (Ba), cobalt (Co), strontium (Sr) and zinc (Zn) by Ecuadorian (NatAllo) and synthetic (SynAllo-1 and SynAllo-2) allophanes were studied as a function of contact time, pH and metal ion concentration using kinetic and equilibrium experiments. The mineralogy, nano-structure and chemical composition of the allophanes were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy and specific surface area analyses. The evolution of adsorption fitted to a pseudo-first-order reaction kinetics, where equilibrium between aqueous metal ions and allophane was reached within < 10 min. The metal ion removal efficiencies varied from 0.7 to 99.7 % at pH 4.0 to 8.5. At equilibrium, the adsorption behavior is better described by the Langmuir model than by the Dubinin-Radushkevich model, yielding sorption capacities of 10.6, 17.2 and 38.6 mg/g for Ba^(2+), 12.4, 19.3 and 29.0 mg/g for HCoO_2^-, 7.2, 15.9 and 34.4 mg/g for Sr^(2+) and 20.9, 26.9 and 36.9 mg/g for Zn^(2+), respectively, by NatAllo, SynAllo-2 and SynAllo-1. The uptake mechanism is based on a physical adsorption process. Allophane holds great potential to remove aqueous metal ions and could be used instead of zeolites, montmorillonite, carbonates and phosphates for wastewater treatment.
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Earth Sciences, Environmental Sciences; gas flaring; SLSTR
Online: 24 June 2018 (08:57:34 CEST)
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Gas flaring is a disposal process widely used in the oil extraction and processing industry. It consists in the burning of unwanted gas at the tip of a stack and due to its thermal characteristic and the thermal emission it is possible to observe and to quantify it from space. Spaceborne observations allows us to collect information across regions and hence to provide a base for estimation of emissions on global scale. We have successfully adapted the Visible Infrared Imaging Radiometer Suite (VIIRS) Nightfire algorithm for the detection and characterisation of persistent hot spots, including gas flares, to the Sea and Land Surface Temperature Radiometer (SLSTR) observations on-board the Sentinel- satellites. A hot event at temperatures typical of a gas flare will produce a local maximum in the night-time readings of the shortwave and mid-infrared (SWIR and MIR) channels of SLSTR. The SWIR band centered at 1.61 mmis closest to the expected spectral radiancemaximumand serves as the primary detection band. The hot source is characterised in terms of temperature and area by fitting the sum of two Planck curves, one for the hot source and another for the background, to the radiances from all the available SWIR, MIR and thermal infra-red channels of SLSTR. The flaring radiative power is calculated from the gas flare temperature and area. Our algorithm differs from the original VIIRS Nightfire algorithm in three key aspects: (1) It uses a granule-based contextual thresholding to detect hot pixels, being independent of the number of hot sources present and their intensity. (2) It analyses entire clusters of hot source detections instead of individual pixels. This is arguably a more comprehensive use of the available information. (3) The co-registration errors between hot source clusters in the different spectral bands are calculated and corrected. This also contributes to the SLSTR instrument validation. Cross-comparisons of the new gas flare characterisation with temporally close observations by the higher resolution German FireBIRD TET-1 small satellite and with the Nightfire product based on VIIRS on-board the Suomi-NPP satellite show general agreement for an individual flaring site in Siberia and for several flaring regions around the world. Small systematic differences to VIIRS Nightfire are nevertheless apparent. Based on the hot spot characterisation, gas flares can be identified and flared gas volumes and pollutant emissions can be calculated with previously published methods.
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Earth Sciences, Environmental Sciences; tree-ring width; Juniperus Turkestanica; climate; temperature minimum; Tajikistan Tian Shan
Online: 20 June 2018 (06:07:51 CEST)
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Despite the ecological importance of forest tree species, our study was motivated by scarce data on dendrochronology studies limited to the northwestern part of Tajikistan due to lack of access to such a part of the country which is difficult to access. Current studies on Junipers in the northwestern part of Tajikistan identified that tree ring-based climate reconstruction is possible. Cores of Juniperus Turkestanica from Taboshar area, Sogd province were developed into 176-year tree-ring width chronology. In the current study a summer (June-September) minimum temperature reconstruction spanning AD 1840–2016 was developed, which can explain 30.0% of the instrumental variableness for the period of 1940–2015. Five warmest (1856–1866, 1869–1871, 1907–1916, 1923–1935, 1988–2016) and four coldest time periods (1840–1855, 1872–1906, 1917–1922, 1940–1984) were identified. The developed reconstruction coincides with cold and warm periods with prior investigations from tree-rings in China, Mongolia, Kyrgyzstan, Kazakhstan and Tajikistan. Spatial correlation analysis with the gridded minimum temperature data shows that the temperature reconstruction covers geographical representation over High Asia. Significant correlation was found between temperature reconstruction with summer SST, which suggests strong linkages of regional temperature variability with Indian-Ocean climate system. The obtained spectral peaks from the spectral analysis of the summer temperature reconstruction were significantly at 84.7-year (90%), 2.9-year (99%), 2.6-year (99%), 2.5-year (99%), 2.4-year (99%) and 2.2-year (99%).
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Earth Sciences, Environmental Sciences; Lead, children's health, zinc, soil, citizen-science
Online: 18 June 2018 (15:14:55 CEST)
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An ambitious citizen-science effort in the city of Indianapolis (Indiana, USA) led to the collection and analysis of a large number of samples at the property scale, facilitating the analysis of differences in soil metal concentrations as a function of property location (i.e., dripline, yard, and street) and location within the city. This effort indicated that dripline soils had substantially higher values of lead and zinc than other soil locations on a given property, and this pattern was heightened in properties nearer the urban core. Soil lead values typically exceeded the levels deemed safe for children’s play areas in the US (<400 ppm), and almost always exceeded safe gardening guidelines (<200 ppm). As a whole, this study identified locations within properties, and cities, that exhibited the highest exposure risk to children, and also exhibited the power of citizen science to produce data at a spatial scale (i.e., within a property boundary) that is usually impossible to feasibly collect in a typical research study.
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Earth Sciences, Environmental Sciences; impervious surface mapping; multi-temporal data; change detection; high-resolution imagery; LiDAR; object-based post-classification fusion
Online: 15 June 2018 (14:32:50 CEST)
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Impervious surface mapping with high-resolution remote sensing imagery has attracted increasing interest as it can provide detailed information for urban structure and distribution. Previous studies have suggested that the combination of LiDAR data and high-resolution imagery for impervious surface mapping performs better than using only high-resolution imagery. However, due to the high cost of the acquisition of LiDAR data, it is difficult to obtain the multi-sensor remote sensing data acquired at the same acquisition time for impervious surface mapping. Consequently, real landscape changes between multi-sensor remote sensing data at different acquisition times would lead to the error of misclassification in impervious surface mapping. This issue has mostly been neglected in previous works. Furthermore, the observation differences generated from multi-sensor data, including the problems of misregistration, missing data in LiDAR data, and shadow in high-resolution images would also challenge the final mapping result in the fusion of LiDAR data and high-resolution images. In order to conquer these problems, we propose an improved impervious surface mapping method incorporating both LiDAR data and high-resolution imagery at different acquisition times in consideration of real landscape changes and observation differences. In the proposed method, a multi-sensor change detection by supervised multivariate alteration detection is employed to obtain changed areas and misregistration areas. The no-data areas in the LiDAR data and the shadow areas in the high-resolution imagery are extracted by independent classification yielded by its corresponding single sensor data. Finally, an object-based post-classification fusion is proposed to take advantage of independent classification results with single-sensor data and the joint classification result with stacked multi-sensor data. Experiments covering the study site in Buffalo, NY, USA demonstrate that our method can accurately detect landscape changes and obviously improve the performance of impervious surface mapping.
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Earth Sciences, Environmental Sciences; bioplastics; seaweed; lactic acid; Life Cycle Assessment; Ulva spp.
Online: 13 June 2018 (16:28:59 CEST)
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An exploratory Life Cycle Assessment was carried out to provide insight into the environmental impacts of using the green seaweed Ulva spp. as a feedstock for production of bioplastic. The study focused on the production of lactic acid as a precursor of polylactic acid. The studied production process consists of (1) the cultivation of Ulva spp. in Integrated Multitrophic Aquaculture, (2) the processing of the biomass for solubilisation of sugars, (3) the fermentation of the sugars to lactic acid and (4) isolation of lactic acid from the fermentation broth. The study identifies environmental hotspots and compares the experimental seaweed production chain with conventional feedstock. The main hotspot identified is electricity consumption during seaweed cultivation. This impact of electricity consumption can be lowered by reducing energy use and sourcing renewable energy, and by improving the material efficiency in the product chain. To improve understanding of the environmental impacts of the production process, future studies can broaden the system boundaries and broaden the scope of sustainability issues included in the environmental assessment.
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Earth Sciences, Environmental Sciences; triggering of debris flows; overland flow; infiltration; laboratory experiments; modelling; rain intensity-duration threshold curves
Online: 13 June 2018 (08:37:32 CEST)
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Many studies, which try to analyze conditions for debris flow development, ignore the type of initiation. Therefore this paper deals with the following questions: What type of hydro-mechanical triggering mechanisms for debris flows can we distinguish in upstream channels of debris flow prone gullies? Which are the main parameters controlling the type and temporal sequence of these triggering processes and what is their influence on the meteorological thresholds for debris flow initiation? A series of laboratory experiments were carried out in a flume, 8 m long and with a width of 0.3 m. to detect the conditions for different types of triggering mechanisms. The flume experiments show a sequence of hydrological processes triggering debris flows, namely erosion and transport by intensive overland flow and by infiltrating water causing failure of channel bed material. On the basis of these experiments an integrated hydro-mechanical model was developed, which describes Hortonian and Saturation overland flow, maximum sediment transport, through flow and failure of bed material. The model was calibrated and validated using process indicator values measured during the experiments in the flume. Virtual model simulations, carried out in a schematic hypothetical source area of a catchment show that slope angle and hydraulic conductivity of the bed material determine the type and sequence of these triggering processes. It was also clearly demonstrated that the type of hydrological triggering process and the influencing geometrical and hydro-mechanical parameters may have a great influence on rainfall intensity-duration threshold curves for the start of debris flows.
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Earth Sciences, Environmental Sciences; fire management; human activities; participation; firewood; charcoal; grazing; water; honey; farming; community forest association
Online: 12 June 2018 (11:20:43 CEST)
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This paper proposes an Integrated Fire Management (IFM) framework that can be used to support communities and resource managers in finding effective and efficient approaches to prevent damaging fires, as well as maintain desirable fire regimes in Kenya. Designing and implementing an IFM approach in Kenya calls for a systematic understanding of the various uses of fire and the underlying perceptions and traditional ecological knowledge of the local people. The here proposed IFM framework allows an evaluation of the risks posed by fires, while balancing them with their beneficial ecological and economic effects, and thus developing effective fire management approaches. A case study of the proposed IFM framework was conducted in Gathiuru Forest that is part of the larger Mt. Kenya Forest Ecosystem. Focus group discussions were held with key resource persons, primary and secondary data on socio-economic activities were studied, fire and weather records were analyzed and the current fire management plans were consulted. Questionnaires were used to assess how the IFM is implemented in the Gathiuru Forest Station. The results show that the proposed IFM framework is scalable and can be applied in places with fire-dependent ecosystems as well as in places with fire-sensitive ecosystems in Kenya. The effectiveness is dependent on the active participation, formulation and implementation of the IFM activities by the main stakeholder groups (Kenya Forest Service (KFS), Kenya Wildlife Service (KWS), and the Community Forest Associations (CFA)). The proposed IFM framework helps in implementing cost-effective approaches to prevent damaging fires and maintain desirable fire regimes in Kenya.
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Earth Sciences, Environmental Sciences; subplinian eruption; co-occurrence matrix; wavelet transform; similarity metrics
Online: 8 June 2018 (12:33:49 CEST)
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This paper presents a new methodology that provides the analysis of surface texture changes in areas adjacent to the volcano and its impact product of volcanic activity. To do this, algorithms from digital image processing such as the co-occurrence matrix and the wavelet transform are used. These methods are working on images taken by the Landsat satellite platform sensor 5 TM and Landsat 7 ETM + sensor, and implemented with the purpose of evaluating superficial changes that can warn of surface movements of the volcano. The results were evaluated by similarity metrics for grayscale images, and validated in two different scenarios that have the same type of eruption, but differ, essentially, in climate and vegetation. Finally, the proposed algorithm is presented, setting the parameters and constraints for implementation and use.
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Earth Sciences, Environmental Sciences; sulfur; reclamation; acid mine drainage; salinity; soil contamination
Online: 7 June 2018 (11:21:57 CEST)
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Sulfur contamination of topsoil, spatial distribution of contamination and surface water chemistry were investigated on an area of over 200 ha of a new forest ecosystem. Common birch and Scots pine growth reaction, vitality and nutrients supply, as well as wood small-reed (Calamagrostis epigejos (L.) Roth) chemical composition were assayed. The chemistry dynamics of soil leaching and the sulfur load leached from the sulfur contaminated soil-substrates were analyzed. The remediation effect of the birch and pine litter was assayed in an experiment under controlled conditions. It was found that reclamation was effective in a majority of the post-mining site, however hot-spots with sulfur contamination reaching even 45,000 mg kg-1, pH <2.0, and EC 6,500 µS cm-1 were reported. Surface waters typically displayed elevated concentrations of sulfate ions (average 935.13 mg L-1), calcium ions (up to 434 mg L-1) and high EC (average 1.795 µS cm-1), which was connected both with sulfur contamination and sludge lime used in neutralization. Wood small-reed was found to be species adapting well to the conditions of elevated soil salinity and sulfur concentration. We noted that an addition of organic matter had a significant impact on the chemistry of soil solutions but did not indicate in short term experiment a remediation effect by increased sulfur leaching.
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Earth Sciences, Environmental Sciences; optimization of planting structure; biannual cropping pattern; arid oasis irrigation area; moderate scale; benefit of unilateral water use
Online: 5 June 2018 (11:08:42 CEST)
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Light and heat resources are ample in Xinjiang plain oasis region. Planting structure is single in irrigation area, which leads to severe seasonal water shortages due to high concentration of water utilization. Therefore, how to make full use of light and heat resources to develop oasis agriculture without expanding planting scale has become the focus of research. The biannual cropping patterns are possible solutions to the problem. Manas River Irrigation area, which is located on the northern slope of Tianshan Mountain in Xinjiang in China is regarded as a typical case study to analyze the suitable planting structure and planting scale for biannual cropping pattern. The effects of optimizing planting patterns on alleviating the contradiction between water supply and water need，and the efficiency of water resources utilization was also studied. The results of the study show that：(1) the suitable planting scales of Manas River irrigation area in wet year (P = 25%), normal year (P = 50%), and low flow year (P = 75%) are about 72.66%, 78.73% and 83.91% of the current planting scale. (2) After the planting structure was optimized, the water use process in the irrigation area extends from May to August at present to April to November. The water use ratio at the peak period of water use decreased from 0.847 to 0.601, and the water use peak was significantly dispersed. (3) Economic benefits per cubic metre of water of the biannual cropping patterns increased from 8.65 yuan·m−3 at present to 9.45 yuan·m−3, 10.31 yuan·m−3 and 11.43 yuan·m−3 in wet year (P = 25%), in normal year (P = 50%) and low flow year (P = 75%) respectively, which proved that replanting crops could improve the efficiency of water resources utilization in irrigated areas. Therefore, the optimal planting pattern can be implemented to improve the utilization efficiency of soil and water resources in irrigation area in the arid oasis with single planting pattern with excessive concentration of water use peak and serious water shortage.
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Earth Sciences, Environmental Sciences; geomorphosites; geomorphosites assessment; Alvão (north of Portugal)
Online: 1 June 2018 (08:27:44 CEST)
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The analysis of the morphological features can be framed in different temporal and spatial scales, depending on the specific objectives and methodologies of the various scientific fields that find in them a valuable source of information. The inventory and assessment of the geomorphological heritage may be based not exclusively in geophysical factors, but also in its contribution to the structuring of the biosphere, in its interrelation with other types of heritage or even in its potential for research or education purposes. In this article, we proceeded to the selection of a set of geomorphosites, at different scales, in Serra do Alvão (northern Portugal), seeking to demonstrate the importance of the broad lines of relief and intermediate and detailed landforms to the organization of the cultural landscape. Based on a questionnaire applied to a sample of 104 persons, it was intended to assess the value of the geomorphosites, concerning the scientific, preservation, use, cultural and educational dimensions.
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Earth Sciences, Environmental Sciences; Water Security, Groundwater assessment, Groundwater quality, India
Online: 31 May 2018 (16:47:27 CEST)
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Achieving water security and availability for all is among the principle agenda of the UN-Sustainable Development Goals. To achieve the goal of water security, particularly in rapidly expanding cities, identification of safe and sustainable water resources is an absolute necessity. The paper conducts an exploratory investigation in the hydro geochemical characteristics of groundwater and thereby, assess the suitability of groundwater as an alternative and reliable resource for public water supply in the Indian city of Surat. A total of 33-groundwater samples, selected on the basis of aquifer depth, land use signatures, were collected from open, bore, dug wells and hand pumps. After the hydrogeochemical analysis, the study evaluated the present state of the groundwater quality and determined the spatial distribution of groundwater quality parameters such as hardness, electrical conductivity, Cl −, pH, SO42-, and NO3 − concentrations. An interpolation technique, known as ordinary kriging, was used to acquire the spatial distribution of parameters of groundwater quality parameters. Based on the permeability index, result showed that 80% of the sampled groundwater quality falls under excellent class i.e. category I with PI value ranging from 1-24%, whereas the rest 20% of the samples has fallen under good class i.e. category II with PI value ranging from 25 to 75% on the suitability of water for irrigation. The results of this study outlines the unsustainability of groundwater for direct consumption, especially without any improved onsite water treatment, but it is appropriate for the irrigation purposes.
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Earth Sciences, Environmental Sciences; remote sensing; python; data management; landsat; open-source
Online: 31 May 2018 (11:12:27 CEST)
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Many remote sensing analytical data products are most useful when they are in an appropriate regional or national projection, rather than globally based projections like Universal Transverse Mercator (UTM) or geographic coordinates, i.e., latitude and longitude. Furthermore, leaving data in the global systems can create problems, either due to misprojection of imagery because of UTM zone boundaries, or because said projections are not optimised for local use. We developed the open-source Irish Earth Observation (IEO) Python module to maintain a local remote sensing data library for Ireland. This pure Python module, in conjunction with the IEOtools Python scripts, utilises the Geospatial Data Abstraction Library (GDAL) for its geoprocessing functionality. At present, the module supports only Landsat TM/ETM+/OLI/TIRS data that have been corrected to surface reflectance using the USGS/ESPA LEDAPS/ LaSRC Collection 1 architecture. This module and the IEOtools catalogue available Landsat data from the USGS/EROS archive, and includes functions for the importation of imagery into a defined local projection and calculation of cloud-free vegetation indices. While this module is distributed with default values and data for Ireland, it can be adapted for other regions with simple modifications to the configuration files and geospatial data sets.
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Earth Sciences, Environmental Sciences; Land-use; satellite imagery; agriculture
Online: 30 May 2018 (17:21:00 CEST)
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The natural and man-made landscape settings in the Khyber Pakhtunkhwa (KPK) province of Northern Pakistan have significantly changed in the last decade due to increasing demands of urbanized populace, migration, two major natural disasters, and climate change. The aim of this study is to analyze land possession, income and land-use diversification of KPK administered Charsadda district. Field data is collected through a sample survey. Furthermore, freely available Landsat 7 satellite images are used to classify land-use classes (e.g. vegetation, built-up) for two different years (e.g. 2005 and 2017) for cross-verification and comparison. The highest 45% of 80% land-owners occupy land-area between 1-10 hectares. Annually, the highest 57.5% of the total farmers / employed in-habitants of surveyed regions earn more than Rs. 100,000 or ~ $ 970 from agriculture activities. About 41.9% land-area covered by agricultural-land is transformed into built-up area since 2007, which is attributed to the increasing demand for buildings and commercial markets. The highest diversification is reported in Naguman area of Charsadda district followed by Rajjar and Niami. Population growth and huge migration of displaced persons from neighboring tribal areas are likely to be few factors which contributed to such a drastic change in land-use pattern since 2007 to 2017. Urgent attention of the policy makers, agricultural experts and society is required to minimize land degradation and to thwart further agricultural-land loss.
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Earth Sciences, Environmental Sciences; drinking water; lead; Pb; flush; exposure prevention; intervention; lead service line
Online: 29 May 2018 (09:39:42 CEST)
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Flushing tap water is often promoted as a simple and low cost approach to reducing water lead exposures. This study evaluated lead reduction when prevailing flush guidelines (30 seconds-2 minutes) are implemented in a city compliant with lead-associated water regulations (New Orleans, LA). Water samples (n=1,497) collected from a convenience sample of 376 residential sites (2015-2017) were analyzed for lead in samples collected: at 1) first draw (n=375), and after incremental flushes of 2) 30-45 seconds (n=375), 3) 2.5-3 minutes (n=373), and 4) 5.5-6 minutes (n=218). There was no significant reduction when compared to the first draw lead level, until the 6 minute flush (p<0.05); but most sites (52%) still had detectable lead (≥1 ppb) after 6 minutes. Older homes (pre-1950) and low occupancy sites had significantly higher WLLs (p<0.05).Each sample type had health-based standard exceedances at over 50% of sites sampled (max: 58 ppb). While flushing is an effective short-term approach to remediate high lead, prevailing flush recommendations are an inconsistently effective exposure prevention measure that can often inadvertently increase exposures. Public health messages should be modified to ensure appropriate application of flushing for specific cities, while acknowledging its short-comings and practical limitations.
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Earth Sciences, Environmental Sciences; transformation; flood risk reduction; Jakarta; risk governance
Online: 29 May 2018 (09:32:27 CEST)
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Jakarta belongs to the cities with the highest flood risk in the world. Its flood hazard is driven by land subsidence, soil sealing, changes in river discharge and increasingly sea level rise. As all of these trends are set to continue, Jakarta’s flood hazard is expected to intensify in the future. Designing and implementing risk reduction and adaption measures is therefore of utmost importance. Against the background, the paper draws on a discourse analysis and original empirical household survey data to review and evaluate current adaptation measures and to analyze in how far they describe a path that is transformative from previous risk reduction approaches. The results show that the focus is clearly on engineering solutions, foremost in the Giant Sea Wall project. The project is likely to transform the city’s flood hydrology. However, it cements rather than transforms the current risk management paradigm which gravitates around the goal of controlling flood symptoms, rather than addressing their anthropogenic root causes. The results also show that the planned measures are heavily contested due to concerns about ecological impacts, social costs, distributional justice, public participation and long-term effectiveness. On the outlook, the results therefore suggest that the more the flood hazard will intensify in the future, the deeper a societal debate will be needed about the desired pathway in flood risk reduction and overall development planning – particularly with regards to the accepted level of transformation, such as partial retreat from the most flood-affected areas.
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Earth Sciences, Environmental Sciences; urban forests; silvicultural treatments; NEXUS; simulation; fire
Online: 25 May 2018 (13:53:53 CEST)
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The peri-urban and urban forests in Greece occupy a total area of 105.353 ha. In these vulnerable ecosystems, fire constitutes a natural disaster presenting particular challenges and specific difficulties. These include the high number of visitors as well as forests characteristics - such as the presence of particularly flammable tree species and high accumulation of combustible biomass – that make the on-start of fires more likely. The main purpose of the current research is to identify the optimum combination of silvicultural treatments to efficiently reduce potential forest fire severity and to facilitate their successful suppression by firefighting crews. In order to simulate the basic fire environment of urban forests, two main experimental plots were established and several tree and topographical characteristics were measured. Additionally, the NEXUS wildfire system was used to simulate forest fire potential behavior before and after the adoption of the silvicultural treatments that altered critical characteristics of the forest fire environment. The results clearly show that specific silvicultural prescriptions altered the type of forest fire spreading potential, revealing the overall efficiency of preventing actions during forest management.
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Earth Sciences, Environmental Sciences; vulnerability; culture; religion; agency; adaptation; perceptions; climate change; dependency
Online: 25 May 2018 (12:06:03 CEST)
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Semi-arid Namibia is marginal for agricultural production. Low soil fertility combined with low and variable rainfall restrict the livelihoods of smallholder farmers who often struggle to produce enough food. Although historically communities have adopted a number of coping mechanisms, climate change threatens to further reduce agricultural production. There are many additional options available to smallholder farmers to adapt to climate change, but they are not necessarily adopting these measures despite having noticed increasing temperatures and declining rainfall. Semi-structured interviews were conducted in three villages in Onesi constituency to examine what agricultural practices smallholder crop farmers use, perception of changes in their yields, their perspective on future yields and whether they are planning on changing their agricultural practices. The results suggest that to sustain the livelihoods of rural communities in north-central Namibia support is needed from local and regional authorities, as well as traditional and religious leaders to assist with enhancing access to information, enabling information sharing on adaptation options, and increasing awareness on climate change, it’s impacts and what can be done about it. In addition to this the implementation of adaptation action also requires demonstration sites and building capacity to enable the development of self-help groups.
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Earth Sciences, Environmental Sciences; Landsat; MODIS; change detection; forest disturbance; forest health
Online: 25 May 2018 (10:48:32 CEST)
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The Operational Remote Sensing (ORS) program leverages Landsat and MODIS data to detect forest disturbances across the conterminous United States (CONUS). The ORS program was initiated in 2014 as a collaboration between the US Department of Agriculture Forest Service Geospatial Technology and Applications Center (GTAC) and the Forest Health Assessment and Applied Sciences Team (FHAAST). The goal of the ORS program is to supplement the Insect and Disease Survey (IDS) and MODIS Real-Time Forest Disturbance (RTFD) programs with imagery-derived forest disturbance data that can be used to augment traditional IDS data. We developed three algorithms and produced ORS forest change products using both Landsat and MODIS data. These were assessed over Southern New England and the Rio Grande National Forest. Reference data were acquired using TimeSync to conduct an independent accuracy assessment of IDS, RTFD, and ORS products. Overall accuracy for all products ranged from 77.64% to 93.51% (kappa 0.09–0.59) in the Southern New England study area and 59.57% to 79.57% (kappa 0.09–0.45) in the Rio Grande National Forest study area. In general, ORS products met or exceeded the overall accuracy and kappa of IDS and RTFD products. This demonstrates the current implementation of ORS is sufficient to provide data to augment IDS data.
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Earth Sciences, Environmental Sciences; decision support; multi-criteria decision analysis; multiple criteria pareto frontier methods; criterium decision plus; net weaver developer; SADfLOR; ecosystem management decision support system
Online: 24 May 2018 (10:35:18 CEST)
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This study examines the potential of combining decision support approaches to identify optimal bundles of ecosystem services. A forested landscape, Zona de Intervenção Florestal of Paiva and Entre-Douro and Sousa (Portugal), is used to test and demonstrate this potential. The landscape extends over 14,000 ha, representing 1,976 stands. The property is fragmented into 376 holdings. The overall analysis was performed in three steps. First, we selected six alternative solutions (A to F) in a Pareto frontier generated by a multiple criteria method within a decision support system (SADfLOR) for subsequent analysis. Next, an aspatial strategic multi-criteria decision analysis (MCDA) analysis was performed with the Criterium DecisionPlus (CDP) component of another decision support system (EMDS) to assess the aggregate performance of solutions A to F for the entire forested landscape with respect to their utility for delivery of ecosystem services. For the CDP analysis, SADfLOR data inputs were grouped into two sets of primary criteria: Wood Harvested and Other Ecosystem Services. Finally, a spatial logic-based assessment of solutions A to F for individual stands of the study area was performed with the NetWeaver component of EMDS. The NetWeaver model was structurally and computationally equivalent to the CDP model, but the key NetWeaver metric is a measure of the strength of evidence that solutions for specific land stands were optimal for the unit. Solutions D and B performed best in the aspatial strategic MCDA analysis, and a composite of the maps generated by NetWeaver demonstrated the spatial basis for the performance of solutions D and B in individual land stands. We conclude with a discussion of how the combination of decision support approaches encapsulated in the two systems could be further automated.
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Earth Sciences, Environmental Sciences; atmospheric pollution; Pb accumulation rate; peat geochemistry; Roman period; Pb isotopes
Online: 22 May 2018 (07:44:10 CEST)
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Two peat cores from two bogs were used to reconstruct high–resolution changes in atmospheric Pb accumulation rate (Pb AR) in Belgium during the Roman period. The two records were compared to assess the reliability of peat cores as archives of atmospheric Pb deposition and to established histories of atmospheric emissions from anthropogenic sources. To address these issues we analyze Pb concentration and isotopes, using ICP-MS, LA-ICP-MS and MC-ICP-MS in two peat sections, spanning 1000 yr each. Lead concentrations in the two cores range from 0.1 to 60 μg g−1, with the maxima between 15 and 60 μg g−1. The average natural background of Pb AR was 0.005± 0.002 mg m-2 yr-1 and the maximum ranges from 0.7 to 1.2 mg m-2 yr-1 between 50 BC and AD 215. The highest Pb AR exceed the pre-Roman period values by a factor of 25-30. Pb isotopic composition indicates that mining and metallurgical activities were the predominant sources of pollution during the Roman period. The Pb AR and chronologies in the Belgian peat cores are consistent with those reported for other continental archives as lake sediments, peat and ice cores.
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Earth Sciences, Environmental Sciences; land degradation; food security; climate change; remote sensing; survey datasets; Kloto district
Online: 16 May 2018 (08:40:46 CEST)
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This study investigates proximate drivers of cropland and forest degradation in Kloto district (Togo, West Africa) as, way of, exploring integrated sustainable landscape approaches in respect to socio-economic and environmental needs and requirements. Net change analysis of major cash and food crops based on three time steps Landsat data (1985–2002, 2002–2017 and 1985–2017) and quantitative analysis from participatory survey data with farmers and landowners are used. Study underlines poor agricultural systems and cassava farming as major impediments to alarming forest losses between 1985–2017. Significant net loss in forests cover by 23.6% and surface areas under cultivation of cocoa agroforestry and maize by 12.99 and 10.1% from 1985 to 2017, due to, intensive cassava cropping (38.78%) and settlement expansions (7.84%). Meanwhile, loss in forest cover between 2017 and 2002 was marginal (8.36%) compared to the period 1985–2002 for which the loss was considerable (15.24%). Based on participatory surveys, majority of agricultural lands are threatened by erosion or physical deterioration (67.5%), land degradation or salt deposits and loss of micro/macro fauna and flora at 56.7%, declining in soil fertility (32.5%), soil water holding capacity (11.7%) and changes in soil texture (3.3%). Majority of farmers adhere to the adoption of the proposed climate smart practices with emphasis on cost effective drip irrigation systems (45.83%), soil mulching (35%) and adoption of drought resilient varieties (29.17%) to anticipate drought spells adverse. The study concludes that low adoption of improved soil conservation, integrated water management and harvesting systems and low productive and adaptive cultivars entail extreme degradation of croplands and crops productivity decline. Therefore, farmers are forced to clear more forests in search of stable and healthy soils for production and extraction of forest products to meet their food demands and improve their livelihoods conditions. Capacity building on integrated pathways of soil and land management practices are therefore needed to ensure sustainable and viable socio-ecological systems at local scale.
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Earth Sciences, Environmental Sciences; chlorpyrifos; cypermethrin; daily intake; home environment; Monte Carlo simulation; non-dietary ingestion; SHEDS model; Taiwan
Online: 15 May 2018 (06:30:06 CEST)
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We estimated the daily intakes of chlorpyrifos and cypermethrin via ingestion of indoor dust and outdoor soils using the Stochastic Human Exposure and Dose Simulation Model on a probabilistic approach for Taiwan’s homes. Variable information for the daily intake estimation, such as concentration, ingestion rate, body weight, was adopted from previous studies. Monte Carlo simulation was performed with 1,000,000 iterations to simulate a single daily intake, which was shown in terms of percentage of the Acceptable Daily Intake (ADI) of either insecticide. The daily intakes were minimal with a 99% probability; at 99.9th percentile, however, the total intakes leaped to 13.1% and 20.0% of the respective ADIs of chlorpyrifos and cypermethrin. The sensitivity analysis indicated that concentration was the most determinant variable. Compared to the data of daily intakes via dietary ingestion of vegetables derived from a previous study, the estimated intakes by this study were considerable at the highest percentile, which referred to insecticide residues few days after insecticide application. Consequently, the non-dietary ingestion exposure to either insecticide was negligible in most cases; nevertheless, for those with indoor insecticide applications, the daily intakes for young children could be of concern. Frequently home cleaning is recommended to reduce the exposure.
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Earth Sciences, Environmental Sciences; deforestation; forest degradation; forest reference level; forest reference emission level; REDD+; intensity analysis; GHG; Togo
Online: 14 May 2018 (12:57:50 CEST)
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Accurate forest reference and emission level (FRL, FREL) with related policies and regulations are the key determinants in establishing sustainable forest ecosystem management programmes (e.g. REDD+). This fundamental is for promoting and sustaining climate smart agricultural practices in a changing climate. With the aim to deliver better knowledge to the scientific community and policy makers on regulations and existing tools for more rigorous scientific communication when it comes to FRL and FREL accountability and policies. Thus, this review investigates forest in the changing climate and policies and underlines the performance of land use transition and intensity analysis towards deforestation with some key examples and achievements (e.g. Togo). Simply put, (i) forest as break of greenhouse gas (GHGs) and ecosystem regulator, (ii) policies and REDD+ actions, (iii) potential drivers and (iv) transition and intensity analysis approach for their accountability are discussed. In sum, impressive studies, policies and regulations are under initiations and implementations regarding the role, place and evaluation of forest losses and its ecosystem functions and services. However, there are still some gaps when it comes to: the choice of the evaluation methods in the real context of a specific ecosystem as well as the firm implementations of formulating policies in developing countries. This paper concludes with some policy measures for forest sustainability, carbon enhancement and accountability.
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Earth Sciences, Environmental Sciences; cyanobacteria; cyanotoxins; nutrient enrichment; akinetes; harmful algal blooms; PCR; phylogenetic analyses
Online: 10 May 2018 (15:37:51 CEST)
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The presence of harmful algal blooms (HABs) and cyanotoxins in drinking water sources poses a great threat to human health. The current study employed molecular techniques to determine the occurrence of non-toxic and toxic cyanobacteria species in the Limpopo River basin based on the phylogenetic analyses of 16S rRNA gene. The bottom sediments samples were collected from selected rivers: Limpopo, Crocodile, Mokolo, Mogalakwena, Nzhelele, Lephalale, Sand Rivers (South Africa); Notwane (Botswana), Shashe River and Mzingwane River (Zimbabwe). The physical-chemical analysis of the bottom sediments showed the availability of nutrients, nitrates and phosphates, in excess of 0.5 mg/l for most of river sediments, alkaline pH and salinity in excess of 500 mg/l. The FlowCam showed the dominant cyanobacteria species identified from the samples were Microcystis species, followed by Cylindrospermopsis raciborskii, Phormidium and Planktothrix species and this was confirmed by molecular techniques. Nevertheless, two samples showed the amplification of cylindrospermopsin polyketide synthetase gene (S3 and S9) while two samples showed amplification for microcystin/nodularin synthetase gene (S8 and S13). Thus these findings may imply the presence of toxic cyanobacteria species in the river sediments. The presence of cyanobacteria may be hazardous to human because rural communities and farmers who abstract water from Limpopo river catchment for human consumption, livestock and wildlife watering and irrigation.
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Earth Sciences, Environmental Sciences; rule-based system; reservoir management model; land management model; SWAT (Soil and Water Assessment Tool)
Online: 10 May 2018 (06:27:38 CEST)
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Decision tables have been used for many years in data processing and business applications to simulate complex rule sets. Several computer languages have been developed based on rule systems and they are easily programmed in several current languages. Land management and river-reservoir models simulate complex land management operations and reservoir management in highly regulated river systems. Decision tables are a precise yet compact way to model the rule sets and corresponding actions found in these models. In this study, we discuss the suitability of decision tables to simulate management in the river basin scale Soil and Water Assessment Tool (SWAT+) model. Decision tables are developed to simulate automated irrigation and reservoir releases. A simple auto irrigation application of decision tables was developed using plant water stress as a condition for irrigating corn in Texas. Sensitivity of the water stress trigger and irrigation application amounts were shown on soil moisture and corn yields. In addition, the Grapevine Reservoir near Dallas, Texas was used to illustrate the use of decision tables to simulate reservoir releases. The releases were conditioned on reservoir volumes and flood season. The release rules as implemented by the decision table realistically simulated flood releases as evidenced by a daily NSE (Nash-Sutcliffe Efficiency) of 0.52 and a percent bias of -1.1%. Using decision tables to simulate management in land, river and reservoir models was shown to have several advantages over current approaches including: 1) mature technology with considerable literature and applications, 2) ability to accurately represent complex, real world decision making, 3) code that is efficient, modular and easy to maintain, and 4) tables that are easy to maintain, support, and modify.
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Earth Sciences, Environmental Sciences; agrobiodiversity; environment; ecosystem; culture; farms; planning
Online: 9 May 2018 (07:37:48 CEST)
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This document presents, from environmental thinking (ecosystem - culture relations), the concept of the Main Agroecological Structure of Agroecosystems (MAS, EAP, for its acronym in Spanish), considered as a dissipative cultural structure. It discusses its possible applications (resilience, production, diversity) both inside and outside the farms. The MAS can be useful in the land planning on the farms, based on the concept of potential MAS that allows the quantification of the management of internal and external corridors, including natural vegetation. At the same time, it can be useful in the context of landscape management because it shows a series of cultural relations (economic, social, symbolic and technological) hidden from the partial analysis of landscape ecology.
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Earth Sciences, Environmental Sciences; water quality; soil structure; threshold electrolyte concentration; zero point of dispersion
Online: 4 May 2018 (07:53:35 CEST)
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The sustainability of irrigated agriculture depends on the quality of irrigation water used. The electrolyte concentration (EC) of irrigation water may lead to the accumulation of salts in the root zone layers and affect the physiological functions of the crop by osmotic and ion toxicity effects. Further, the cationic and anionic composition of the water may alter the exchangeable cation composition of the soil and as well as its pH. Because of the dominance of sodium salts in many sources of irrigation water, parameters related to sodium such as exchangeable sodium percentage (ESP) of soils and sodium adsorption ratio (SAR) of soil solutions have been commonly used to study the effects of sodium in irrigation water on soil structural stability. Quirk and Schofield concept of ‘threshold electrolyte concentration’ (TEC) has shown the importance of electrolytes in preventing the effects of sodium on soil structure. Based on this concept, several models have been proposed to relate ESP or SAR with EC to predict the possible impacts of irrigation water on soil structural stability. However, many research reports indicate that this relationship varies with soils and a given model is not suitable for all types of soils. Further, the effects of potassium and magnesium in the processes leading to clay dispersion are disregarded in these models. This essay analyses all the factors involved in the structural failure of soils with different cationic composition, identify the defects in these TEC models and re-defines TEC on the basis of new insights on dispersive and flocculating charges of soils. This review does not deal with EC effects on crops and also the role of contaminant ions not involved with soil structural stability.
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Earth Sciences, Environmental Sciences; water-reuse; governance capacity; water management; water scarcity
Online: 3 May 2018 (08:36:07 CEST)
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The world will experience an estimated 40% freshwater supply shortage by 2030, converting water scarcity into one of the principal global challenges that modern society face. Urban water-reuse is recognized as a promising and necessary measure to alleviate the growing water stress in many regions. The transformation to widespread application of water-reuse systems requires major changes in the way water is governed, and countries such as Spain already find themselves involved in this process. Through the systematic assessment of the city of Sabadell (Spain), we aim to identify the main barriers, opportunities and transferable lessons that can enhance governance capacity to implement systems for non-potable reuse of treated wastewater in cities. It was found that continuous learning, the availability and quality of information and level of knowledge and strong agents of change are the main capacity-building priorities. On the other hand, awareness, multilevel network potential and implementing capacity are already well-established. It is concluded that in order to undertake a widespread application of water-reuse practices, criteria examining water quality according to its use need to be developed, independently of the water’s origin. The development and implementation of such a legislative frame should be based on the experience of local water-reuse practices and continuous evaluation. Finally, the need for public engagement and adequate pricing mechanisms are emphasized.
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Earth Sciences, Environmental Sciences; decision dilemma; intergenerational welfare; time horizon; risk attitude; inequality aversion; fairness; responsibility; sustainability paradigms
Online: 2 May 2018 (12:41:08 CEST)
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We introduce and analyse a simple formal thought experiment designed to reflect a qualitative decision dilemma humanity might currently face in view of climate change. In it, each generation can choose between just two options, either setting humanity on a pathway to certain high wellbeing after one generation of suffering, or leaving the next generation in the same state as this one with the same options, but facing a continuous risk of permanent collapse. We analyse this abstract setup regarding the question of what the right choice would be both in a rationality-based framework including optimal control, welfare economics and game theory, and by means of other approaches based on the notions of responsibility, safe operating spaces, and sustainability paradigms. Despite the simplicity of the setup, we find a large diversity and disagreement of assessments both between and within these different approaches.
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Earth Sciences, Environmental Sciences; environmental health; risk communication; risk management; particulate matter; risk analysis; mass event
Online: 27 April 2018 (05:15:54 CEST)
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Atmospheric pollution arising from diesel-powered engines can result in acute and chronic diseases of the respiratory and cardiovascular systems. The annual carnival festival that takes place in the city of Salvador, Bahia-Brazil, is a large-scale event that gathers approximately 2 m revelers and 170,000 workers who accompany dozens of sound-trucks, or trios elétricos, for a period of seven days. These slow-moving sound-trucks run on diesel fuel, constantly exposing those around them to exhaust fumes. The present study aimed to evaluate air quality along the approximately 10km-long carnival parade circuit and determine possible impacts on human health. We applied a three-phase risk analysis strategy from 2007–2009: 1) hazard identification, 2) risk characterization and 3) risk management. Our quantification of atmospheric particulate matter 2.5 (PM2.5) and nitrogen dioxide (NO2) concentrations revealed variable levels of PM2.5 ranging from 19 µg/m3 to 580 µg/m3, with peaks of up to 800 μg/m3 at sound-truck concentration areas. We then assessed the effects of air pollution on human health using ophthalmologic parameters obtained from 28 carnival volunteers, who often presented symptoms of eye irritation. Finally, we established strategies to communicate the study’s objectives and obtained results to the population through media outlets and open discussions with government agencies. According to our risk analysis, carnival sound-trucks represent the main source of atmospheric PM2.5 and NO2 pollution during the annual 7-day carnival festival. As a consequence of our research, the municipal government of Salvador issued an addendum to its carnival legislation mandating organizers to monitor atmospheric pollution, and, subsequently, all large-scale public events. Municipal government authorities have also promoted a shift from petroleum-based diesel fuel to biodiesel, a less-polluting fuel, for all adapted carnival sound-trucks. Our approach, which employed easily accessible and inexpensive methodology, provided substantial scientific evidence to support improvements in the regulation of air quality during large-scale public events held in the city of Salvador.Keywords: environmental
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Earth Sciences, Environmental Sciences; gold nanoparticle; fungi; nanoparticle shape; nanoparticle size; nanotoxicology
Online: 25 April 2018 (07:47:04 CEST)
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The possibility of releasing gold nanoparticles (GNP) into the environment has been rapidly increasing with the wide spread and flourishing application of gold nanoparticles (GNPs) in a wide range of areas. Consequently, environmental effects of GNP, especially toxicities to living organisms have drawn great attention. However, their toxicological characteristics still remain unclear. Fungi, as the decomposers of the ecosystem, interact directly with the environment and critically control the overall health of the biosphere. Thus, their sensitivity to GNP toxicity is particularly important. The aim of this study was to evaluate the role of shape and size of GNPs on their toxicities to fungi, which could help reveal the ecotoxicity of GNPs. Aspergillus niger, Mucor hiemalis and Penicillium chrysogenum were chosen for toxicity assessment, and spherical and star/flower-shaped GNPs sized from 0.7 nm to large aggregates of 400 nm have been synthesised. After exposure to GNPs and their corresponding reaction agents and incubation for 48 hours, the survival rates of each kind of fungus was calculated and compared. The results indicated that fungal species was the major determinant of the variation of survival rates, whereby A. niger was most sensitive and M. himalis was least sensitive to GNP exposure. Additionally, larger and non-spherical GNPs had relatively stronger toxicities.
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Earth Sciences, Environmental Sciences; semi-arid steppe region; large-scale coal-power base; landscape ecological classification
Online: 23 April 2018 (12:48:59 CEST)
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The ecological background condition of the semi-arid steppe region (SASR) is extremely fragile. It is recognized that the development of coal and electricity power is a kind of strong human interference behavior for regional landscape ecology. Landscape ecological classification (LEC) is the premise of landscape ecology research of the mining area. The current research on the SASR and grassland LEC of coal-power base is relatively less, but still remains uncertainty concerning how to stratify and classify urban mining landscapes into units of ecological significance at spatial scales appropriate for management. This study is based on hierarchy theory, scale theory, landscape process, the patch-corridor-matrix model, the network, the theory of multiple planning integration and the principle of remote sensing. According to the comprehensive principle, principles of the combining of structure and function, principle of the combining human-ominated and natural landscape, principle of emphasis, and principle of combining qualitative analysis with quantitative research of LEC in large-scale coal-power base(LSCPB). On the basis of occurrence method land classification, fully consider the ecological attributes of the land, integration pattern, processes and function theory of the landscape ecology, the LEC system of the LSCPB in the SASR has been constructed by using top-down decomposition classification method. Empirical research of the Victory and Mindong No.1 mining areas of Shenhua Group shows that the classification system constructed in this paper can meet the requirements of LEC and fully reflect the status of landscape ecology of LSCPB in SASR. This study can provide theoretical guidance for the landscape ecology of LSCPB, while also supporting a theoretical reference for the LEC research.
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Earth Sciences, Environmental Sciences; renewable energy sources; life quality; RES public acceptance; logit regression
Online: 17 April 2018 (10:18:42 CEST)
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The aim of this paper is to analyze and evaluate Renewable Energy Sources (RES) usage and their contribution to citizens’ life quality. For this purpose, a survey was conducted, using a sample of 400 residents in an urban area of Attica region in Greece. The methods of Principal Components Analysis and Logit Regression were used on a dataset containing respondents’ views on various aspects of RES. Two statistical models were constructed for the identification of the main variables that are associated with RES’ usage and respondents’ opinion on their contribution to life quality. The conclusions that can be drawn show that the respondents are adequately informed about some of the RES’ types while most of them use at least one of the examined types of RES. The benefits that RES offer, were the most crucial variable in determining both respondents’ perceptions on their usage and on their contribution to life quality.
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Earth Sciences, Environmental Sciences; soil salinity; arid; semi-arid; Landsat 8 OLI
Online: 16 April 2018 (10:18:42 CEST)
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Soil salinity, whether natural or human induced, is a major geo-hazard in arid and semi-arid landscapes. In agricultural lands, it negatively affects plant growth, crop yields, whereas in semi-arid and arid non-agricultural areas it affects urban structures due to subsidence, corrosion and ground water quality, leading to further soil erosion and land degradation Accurately mapping soil salinity through remote sensing techniques has been an active area of research in the past few decades particularly for agricultural lands. Most of this research has focused on the utilization and development of salinity indices for properly mapping and identifying saline agricultural soils. This research study develops a soil salinity index and model using Landsat 8 OLI image data from the near infra-red and shortwave infra-red spectral information with emphasis on soil salinity mapping and assessment in non-agricultural desert arid and semi-arid surfaces. The developed index when integrated into a semi-empirical model outperformed in its soil salinity mapping overall accuracy (60%) in comparison to other salinity indices (~50%). The newly developed index further outperformed other indices in its accuracy in mapping and identifying high saline soils (67%) and excessively high saline soils (90%).
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Earth Sciences, Environmental Sciences; UAV; multi-spectral; lychee; pruning; tree crop structure; change detection
Online: 16 April 2018 (08:56:39 CEST)
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Unmanned aerial vehicles (UAV) provide an unprecedented capacity to monitor the development and dynamics of tree growth and structure through time. It is generally thought that the pruning of tree crops encourages new growth, has a positive effect on fruiting, makes fruit-picking easier, and may increase yield, as it increases light interception and tree crown surface area. To establish the response of pruning in an orchard of lychee trees, an assessment of changes in tree structure, i.e. tree crown perimeter, width, height, area and Plant Projective Cover (PPC), was undertaken using multi-spectral UAV imagery collected before and after a pruning event. While tree crown perimeter, width and area could be derived directly from the delineated tree crowns, height was estimated from a produced canopy height model and PPC was most accurately predicted based on the NIR band. Pre- and post-pruning results showed significant differences in all measured tree structural parameters, including an average decrease in tree crown perimeter of 1.94 m, tree crown width of 0.57 m, tree crown height of 0.62 m, tree crown area of 3.5 m2, and PPC of 14.8%. In order to provide guidance on data collection protocols for orchard management, the impact of flying height variations was also examined, offering some insight into the influence of scale and the scalability of this UAV based approach for larger orchards. The different flying heights (i.e. 30, 50 and 70 m) produced similar measurements of tree crown width and PPC, while tree crown perimeter, area and height measurements decreased with increasing flying height. Overall, these results illustrate that routine collection of multi-spectral UAV imagery can provide a means of assessing pruning effects on changes in tree structure in commercial orchards, and highlight the importance of collecting imagery with consistent flight configurations, as varying flying heights may cause changes to tree structural measurements.
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Earth Sciences, Environmental Sciences; manometric tests; liquid phase test; SOUR; stability; organic substrates; respiration activity; respirometry
Online: 6 April 2018 (18:38:51 CEST)
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The stability of twenty seven composts and organic substrates (including raw, less stable and stable materials) was assessed using two different liquid phase tests were carried out. One of the tests was introduced in 1998 and was based on the calculation of a Specific Oxygen Uptake Rate (SOUR). The newly introduced liquid phase test presented here is simpler to set-up and to perform that the older liquid phase test. It is based on the quantification of oxygen consumption in the headspace of a BOD bottle that contains the liquid-solid solution. The results indicate that a marginal correlation does exist between the main indices calculated from both tests. The correlation was stronger for the indices calculated for stable-processed organics than for the raw (unprocessed materials). The SOUR ranged from 1520 to 3650mg O2/kg VS-h for the raw materials and from 110 to 1150 mg O2/kg VS-h for the processed materials, respectively. The corresponding stability rate related index (LSRI24) of the new liquid phase test introduced here ranged from 240 to 1180 mg O2/dry kg-h for the raw materials and from 64 to 792 mg O2/dry kg-h for the processed ones.
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Earth Sciences, Environmental Sciences; pollutant transport modelling; metals transport modelling; free surface water bodies; toxics-reaction equation
Online: 2 April 2018 (11:27:40 CEST)
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This paper describes the development of a two-dimensional water quality model that solves hydrodynamic equations tied to transport equations with reactions mechanisms inherent in the processes. This enable us to perform an accurate assessment of the pollution in a coastal ecosystem. The model was developed with data drawn from the ecosystem found in Mexico's southeast state of Tabasco. The coastal ecosystem consists of the interaction of El Yucateco lagoon with the Chicozapote and Tonalá rivers, that connect the lagoon with the Gulf of Mexico. We present the results of pollutants transport simulation in the coastal ecosystem, focusing on toxic parameters for two hydrodynamic scenarios: wet and dry seasons. As it of interest in the zone, we study the transport of four metals: Cadmium, Chromium, Nickel and Lead. In order to address our objectives we solved numerically a self-posed mathematical problem,which is based on the measured data. The performed simulations show to characterise metal transport within the acceptable range of accuracy and in accordance with the measured data. The performed simulations show to characterise metals transport with an acceptable accuracy, agreeing well with measured data in total concentrations in four control points along the water body. Although for the accurate implementation of the hydrodynamic-based water quality model herein presented, boundary (geometry, tides, wind, etc.) and initial (concentrations measurements) conditions are required, it poses as an excellent option when the distribution of solutes with high accuracy is required, easing environmental, economic and social management of coastal ecosystems.
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Earth Sciences, Environmental Sciences; severity mapping; regression models; maximum likelihood; GeoCBI; dNBR; RdNBR; RBR
Online: 29 March 2018 (06:06:32 CEST)
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The severity of forest fires derived from remote sensing data for research and management has become increasingly widespread in the last decade, where these data typically quantify the pre- and post-fire spectral change between satellite images on multi-spectral sensors. However, there is an active discussion about which of the main indices (dNBR, RdNBR or RBR) is the most adequate to estimate the severity of the fire, as well about the adjustment model used in the classification of severity levels. This study proposes and evaluates a new technique for mapping severity as an alternative to regression models, based on the use of the maximum likelihood estimation (MLE) automatic learning algorithm, from GeoCBI field data and spectral indices dNBR, RdNBR and RBR applied to Landsat TM, ETM+ Images, for two fires in central Spain. We compare the severity discrimination capability on dNBR, RdNBR and RBR, through a spectral separability index (M) and then evaluated the concordance of these metrics with field data based on GeoCBI measurements. Specifically, we evaluated the correspondence (R2) between each metric and the continuous measurement of fire severity (GeoCBI) and the general precision of the regression and MLE models, for the four categorized levels of severity (Unburned, Low, Moderate, and High). The results show that the RBR has more spectral separability (average between two fires M = 2.00) that the dNBR (M = 1.82) and the RdNBR (M=1.80), additionally the GeoCBI has a better adjustment with the RBR of (R2 = 0.73), than the RdNBR (R2 = 0.72), and dNBR (R2 = 0.71). Finally, the overall classification accuracy achieved with the MLE (Kappa = 0.65) has a better result than regression models (Kappa = 0.58) and higher accuracy of individual classes.
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Earth Sciences, Environmental Sciences; wetland vegetation; normalized difference vegetation index (NDVI); Landsat; precipitation; air temperature; snowmelt; extremely arid regions
Online: 28 March 2018 (06:13:23 CEST)
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Based on 541 Landsat images between 1988 and 2016, the normalized difference vegetation indices (NDVIs) of the wetland vegetation at Xitugou (XTG) and Wowachi (WWC) inside the Dunhuang Yangguan National Nature Reserve (YNNR) in northwest China were calculated for assessing impacts of climate change on wetland vegetation in the YNNR. It was found that the wetland vegetation at the XTG and WWC both had shown a significant increasing trend in the past 30 years, and the increase in both annual mean temperature and peak snow depth over the Altun Mountains led to the increase of wetland vegetation. The influence of local precipitation on the XTG wetland vegetation was greater than on the WWC wetland vegetation, which demonstrates that in extremely arid regions, the major constrain to the wetland vegetation is water availability in soils which is greatly related to the surface water detention and discharge of groundwater. At both XTG and WWC, snowmelt from the Altun Mountains is the main contributor to the groundwater discharge, while local precipitation plays a less role in influencing the wetland vegetation at the WWC than at the XTG, because the wetland vegetation grows on a relatively flat terrain at the WWC, while in a stream channel at the XTG.
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Earth Sciences, Environmental Sciences; thermal comfort; green spaces; South American city; urban morphology; climate perception
Online: 23 March 2018 (05:03:39 CET)
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This paper presents a research carried out in the city of Chillan, a medium size city located on the southern limit of the Chilean Mediterranean domain, at 36º 36`s south latitude. Chillán provides a good representative example of warm summers in central and southern Chilean cities. Five public spaces were selected, representing different typologies and relating to different urban background conditions. Users in these public spaces were observed, counted and photographed five times a day (12, 14, 16, 18 and 20 hours, local time) during a heat wave event in the summer of 2016, while meteorological parameters were established at different points within the public space. The variables evaluated were impervious surfaces, Skyview factor, H/W, azimuth, shadow and radiation. Local public environmental management should pay attention to the complex relations between urban climate, public spaces and thermal comfort since they affect the quality of life of the most vulnerable sectors of the population. This is particularly important given the increasing episodes of high temperatures and intense heat waves occurred in the city of Chillán in recent summers, which are related to urban heat islands and climate change.
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Earth Sciences, Environmental Sciences; local climate change; spring drying; rainfall pattern changes
Online: 22 March 2018 (03:59:30 CET)
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The City of Pasadena is located in southern California; a region which has a Mediterranean climate and where the vast majority of rainfall occurs between October and April with the period between January and March being the most intense. A significant amount of the local water supply comes from regional rainfall, therefore any changes in precipitation patterns in the area has considerable significance. HYPOTHESIS: Local climate change has been occurring in the Pasadena area over the last 100 years resulting in changes in air temperature and rainfall. AIR TEMPERATURES: Between 1886 and 2016 the air temperature in Pasadena, California has increased significantly, from a minimum of 23.8°C in the daytime and 8.1°C at night between 1911 and 1920 to 27.2°C and 13.3°C between 2011 and 2016. The increase in nighttime temperature was uniform throughout the year, however daytime temperatures showed more seasonal variation. There was little change in the daytime temperatures May through July but more change the rest of the year. For example, the median daytime temperature for June between 1911 and 1920 was 27.9°C but was 28.7°C between 2011 and 2016, a difference of 0.8°C. In contrast, for October for the same periods the median daytime temperatures were 25.6°C and 28.9°C, a difference of 3.3°C. RAINFALL: There has been a change in local rainfall pattern over the same period. In comparing rainfall between 1883 – 1949 and 1950 – 2016, there appeared to be less rainfall in the months of October, December, and April while other months seemed to show no change in rainfall. For example, between the two periods mentioned above, the median rainfall in October was 12.4 mm and 8.9 mm respectively while for December they were 68.6 mm and 40.4 mm. There was comparatively a smaller change in the median volume of rainfall in April (18.8 mm vs. 17.5 mm). However, between 1883 and 2016 there were 13 with less than 1 mm of rain, 12 of which occurred after 1961. In the same line of logic, no measureable amount of rain occurred for 23 Octobers, 15 of those occurred after 1961. CONCLUSION: As air temperatures increased over the last 100 years in the Pasadena area, rainfall may have decreased in October, December, and April.
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Earth Sciences, Environmental Sciences; artificial wetlands; horizontal wetland; subsurface flow
Online: 20 March 2018 (07:44:13 CET)
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Currently, several researchers are working to improve the artificial wetlands performance and make them a competitive alternative to conventional treatment mechanisms. In the same vein, this paper analyzes the performance of subsurface flow wetlands removal by COD concentration, suggesting two different hydrodynamic solutions. Firstly, we worked on wetlands at pilot scale and in a real-scale wetland. This subsurface flow wetlands behaviour (HFSS) and its elimination results of organic matter were evaluated in function on the configuration and structure of the capture and evacuation effluent device. The traditional and innovative capture and evacuation effluent device were compared. In this experience, this innovative device designed for the collection and effluent evacuation was applied for the first time, what is in a process of patenting and constitutes an unprecedented improvement in wastewater treatment through HFSS. This innovative tool for capture and evacuation of the effluent, was designed and built to cover the entire width and height of the wetland, its incidence is in the entire cross-sectional area of the flow. The results show that the incorporation of the innovative device improves the wetland hydrodynamic condition, increasing the biodegradation yields of the carbonaceous organic matter. The HFSS behaviour was evaluated using both effluent capture and exit devices, comparing the respective removal efficiencies of organic matter and nitrogen. We analyzed the HFSS behaviour using both configurations (devices), evaluated and determined the incidence in the elimination efficiency of COD and nitrogen in both devices. Using the innovative effluent outlet device, the COD removal performance exceeds that of the conventional device by 10%. The improvement of the yield will allow the reduction of wetland surfaces for the same treatment horizon or the same pollutant load.
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Salvatore Manfreda,
Matthew McCabe,
Pauline Miller,
Richard Lucas,
Victor Pajuelo Madrigal,
Giorgos Mallinis,
Eyal Ben Dor,
David Helman,
Lyndon Estes,
Giuseppe Ciraolo,
Jana Müllerová,
Flavia Tauro,
M. Isabel De Lima,
Joao L.M.P. De Lima,
Felix Frances,
Kelly Caylor,
Marko Kohv,
Antonino Maltese,
Matthew Perks,
Guiomar Ruiz-Pérez,
Zhongbo Su,
Giulia Vico,
Brigitta Toth
Earth Sciences, Environmental Sciences; UAS; remote sensing; environmental monitoring; precision agriculture; vegetation indices; soil moisture; river monitoring
Online: 14 March 2018 (02:38:42 CET)
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Environmental monitoring plays a central role in diagnosing climate and management impacts on natural and agricultural systems, enhancing the understanding hydrological processes, optimizing the allocation and distribution of water resources, and assessing, forecasting and even preventing natural disasters. Nowadays, most monitoring and data collection systems are based upon a combination of ground-based measurements, manned airborne sensors or satellite observations. These data are utilized in describing both small and large scale processes, but have spatiotemporal constraints inherent to each respective collection system. Bridging the unique spatial and temporal divides that limit current monitoring platforms is key to improving our understanding of environmental systems. In this context, Unmanned Aerial Systems (UAS) have considerable potential to radically evolve environmental monitoring. UAS-mounted sensors offer an extraordinary opportunity to bridge the existing gap between field observations and traditional air- and space-borne remote sensing, by providing not just high spatial detail over relatively large areas in a cost-effective way, but as importantly providing an entirely new capacity for enhanced temporal retrieval. As well as showcasing recent advances in the field, there is also a need to identify and understand the potential limitations of UAS technology. For these platforms to reach their monitoring potential, a wide spectrum of unresolved issues and applications specific challenges require focused community attention. Indeed, to leverage the full potential of UAS-based approaches, sensing technologies, measurement protocols, post-processing techniques, retrieval algorithms and evaluations techniques need to be harmonized. The aim of this paper is to provide a comprehensive general overview of the existing research on studies and applications of UAS in environmental monitoring in order to suggest users and researchers on future research directions, applications, developments and challenges.
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Earth Sciences, Environmental Sciences; streamflow; runoff model GR4J; performance; simulation; watershed; Bonou;
Online: 12 March 2018 (14:03:11 CET)
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The study aims to analyze the performance criteria of the GR4J model to reproduce high water flows in the Ouémé watershed at Bonou's outlet which has been vulnerable to climate change in recent decades. The methodology focused on the use of daily climatological and hydrometric data extracted from files of National Directorate of Meteorology, and General Directorate of Water; they were supplemented by those of SIEREM/HSM dataset over the period 1961-2015. The rainfall was regionalized using Thiessen method. The performance of the GR4J model was assessed with NSE, RMSE and KGE criteria. The results indicate that the study area is marked by rainfall variabilities and detection of two breakpoints (1968 and 1987) which divide the series into three sub-periods; these discontinuities have repercussions on the streamflow. It's found that GR4J model overestimates the streamflow during the low water period and underestimates them in high water. However, the efficiency and performance criteria NSE, RMSE and KGE calculated on high water flow rates are better in calibration than in validation. The KGE values are range between 83-85% in calibration and 56-68% during validation, which gives to GR4J model the efficiency and performance to reproduce high flow rates in the study area
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Earth Sciences, Environmental Sciences; Shared Socioeconomic Pathways; climate change; vulnerability; projections; Europe
Online: 8 March 2018 (10:16:59 CET)
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The Shared Socioeconomic Pathways (SSPs) are the new global development trends that inform global and regional climate change research. They have the potential to foster the integration of socioeconomic scenarios within assessments of future climate-related health impacts. To date, such assessments have primarily superimposed climate scenarios on current socioeconomic conditions only. Until now, the few assessments of future health risks that employed the SSPs have focused on future human exposure—i.e., mainly future population patterns—neglecting future human vulnerability. This paper first explores the research gaps—mainly linked to the paucity of available projections—that explain such a lack of consideration of human vulnerability under the SSPs. It then highlights the need for projections of socioeconomic variables covering the wide range of determinants of human vulnerability, available at relevant spatial and temporal scales, and accounting for local specificities through sectoral and regional extended versions of the global SSPs. Finally, this paper presents two innovative methods of obtaining and computing such socioeconomic projections under the SSPs—namely the scenario matching approach and an approach based on experts’ elicitation and correlation analyses—and applies them to the case of Europe. They offer a variety of possibilities for practical application, producing projections at sub-national level of various drivers of human vulnerability such as demographic and social characteristics, urbanization, state of the environment, infrastructure, health status, and living arrangements. Both the innovative approaches presented in this paper and existing methods—such as the spatial disaggregation of existing projections and the use of sectoral models—show great potential to enhance the availability of relevant projections of determinants of human vulnerability. Assessments of future climate-related health impacts should thus rely on these methods to account for future human vulnerability—under varying levels of socioeconomic development—and to explore its influence on future health risks under different degrees of climate change.
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Earth Sciences, Environmental Sciences; human urine; biomonitoring; chlorophenol; demographic characteristics
Online: 8 March 2018 (09:50:42 CET)
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Humans are exposed to the environmental pollutants 2, 4-dichlorophenol (2, 4-DCP) and 2, 5-dichlorophenol (2, 5-DCP) through air, use of water and consuming products. In this study, we evaluated the urinary concentrations of these compounds in Korean people from the age of 18 to 69 years by making use of the data from the Korean National Human Biomonitoring Survey that was completed in 2009. Of 1,865 representative Koreans, 63.4% and 97.9% were found to have concentrations of 2, 4-DCP and 2, 5-DCP > 0.05 μg/L (limit of detection) in their urine. The geometric mean urinary concentrations were 0.14 μg/L (confidence interval of 95% = 0.13–0.16) and 0.44 μg/L (confidence interval = 0.41–0.48), respectively. It was fond that the adjusted proportional changes in 2, 4-DCP concentrations were significantly associated with body mass index, whereas those of 2, 5-DCP concentrations were influenced by place of residence. From these findings, it is evident that most adults in Korea have levels of 2, 4-DCP and 2, 5-DCP that are detectable in their urine and burden of these compounds on their bodies varies depending on numerous demographic factors.
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Earth Sciences, Environmental Sciences; ocean acidification; acid sulphate soils; calcification; molluscs; snails; tropical
Online: 2 March 2018 (10:41:37 CET)
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Marine water pH is becoming progressively reduced in response to atmospheric CO2 elevation. Considering that marine environments support a vast global biodiversity and provide a variety of ecosystem functions and services, monitoring of the coastal and intertidal water pH assumes obvious significance. Because current monitoring approaches using meters and loggers are typically limited in application in heterogeneous environments and are financially prohibitive, we sought to evaluate an approach to acidification biomonitoring using living gastropod shells. We investigated snail populations exposed naturally to corrosive water in Brunei (Borneo, South East Asia). We show that surface erosion features of shells are generally more sensitive to acidic water exposure than other attributes (shell mass) in a study of rocky-shore snail populations (Nerita chamaeleon) exposed to greater or lesser coastal geochemical acidification (acid sulphate soil seepage, ASS), by virtue of their spatial separation. We develop a novel digital approach to measuring the surface area of shell erosion. Surficial shell erosion of a muddy-sediment estuarine snail, Umbonium vestiarium, is shown to capture variation in acidic water exposure for the timeframe of a decade. Shell dissolution in Neripteron violaceum from an extremely acidic estuarine habitat, directly influenced by ASS inflows, was high variable among individuals. In conclusion, gastropod shell dissolution potentially provides a powerful and cost-effective tool for rapidly assessing marine pH change across a range of spatial and temporal frameworks and coastal intertidal environments. We discuss caveats when interpreting gastropod shell dissolution patterns.
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Earth Sciences, Environmental Sciences; Water Treatment, Filtration, Modified Perlite, Optical density, wastewater
Online: 27 February 2018 (16:02:02 CET)
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Water treatment efficiency of several filter media such as perlite, modified (silicated) perlite, zeolite and sand were studied on wastewater. This study contains 2 distinct experiments which the first one emphasize on the modified perlite’s performance in removing turbidity which has been gone through 3 phases including low turbidity model water, mid turbidity and high turbidity model water; the second experiment underlines the differentiation between 3 evolutionary material based on perlite which undergoes the filtration process with certain turbid model water. It was dedicated that modified perlite removed more than 90% of turbidity and it functions better than other materials with high turbidity (more than100 NTU). The experiments have been conducted with sodium silicate perlite, normal perlite and synthetic zeolite perlite in order to determine the optimized material which is able to be substituted with perlite in the filtration process.
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Earth Sciences, Environmental Sciences; shortcut nitrification; constructed rapid infiltration system; potassium chlorate inhibition; domestic sewage
Online: 27 February 2018 (08:50:13 CET)
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Constructed rapid infiltration system (CRI) is a new type of sewage biofilm treatment technology, but due to its anaerobic zone lacks of the carbon sources and the condition for nitrate retention, its nitrogen removal perfomance is very poor; However, shortcut nitrification-denitrification process presents distinctive advantages, as it saves oxygen, requires less organic matter and needs less time for denitrification compared to conventional nitrogen removal method. Thus, if the shortcut nitrification-denitrification process could be applied to CRI system properly, the simpler, more economic and efficient nitrogen removal method will be obtained. But, as its reaction process shows that the first and the most important step of achieving shortcut nitrification-denitrification is to achieve shortcut nitrification. Thus, in this study, we explored the feasibility to achieve shortcut nitrification, which produces nitrite as the dominant nitrogen species in effluent, by addition of potassium chlorate (KClO3) to the influent. In an experimental CRI model system, the effects on nitrogen removal, nitrate inhibition and nitrite accumulation were studied, and the advantages of achieving shortcut nitrification-denitrification were also analysed. The results showed that shortcut nitrification was successfully achieved and maintained in a CRI system by adding 5 mM KClO3 to the influent at a constant pH of 8.4. Under these conditions nitrite accumulation rate was increased, while a lower concentration of 3 mM KClO3 had no obvious effect. The addition of 5 mM KClO3 in influent presumably allowed sufficient activity of ammonia-oxidizing bacteria (AOB) but inhibited nitrite-oxidizing bacteria (NOB) strongly enough to result in a maximum nitrite accumulation rate of up to over 80%. As a result, nitrite became the dominant nitrogen product in the effluent. Moreover, if the shortcut denitrification will be achieved in the subsequent research, it could save 60.27 mg carbon source (CH3OH) consumption when treatment of per liter sewage in CRI system compared with full denitrification process.
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Earth Sciences, Environmental Sciences; peat; electrical conductivity; magnetic susceptibility; K-means clustering; loss on ignition (LOI); organic soils; mineral soils; Indonesia
Online: 27 February 2018 (05:21:36 CET)
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Various type of soils have been identified based on their electrical and magnetic properties, especially with regards to peat soils. Peat soils are commonly considered as partly decomposed vegetation. In this study, electrical and magnetic properties have been used in K-means clustering to identify layers of peat soils. K-means clustering is a partitioning method that treats observations in the data. Data cores were obtained at every centimeter and examined for their electrical conductivity (σ) and magnetic susceptibility (χm) properties. A 291 cm core was obtained at Tegal Arum Village in South Kalimantan, Indonesia. The K-means clustering results indicate two different layers at 148 cm, and this is supported by loss on ignition (LOI) measurements. In the first layers, a 87.65% LOI was found associated with peat soils (above 248 cm). Whereas, in the second layers, there was a 26.11% LOI associated with mineral soils (below 248 cm). The results of this study using K-means clustering can be used to delineate soil layers.
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Earth Sciences, Environmental Sciences; rocky desertification; MESMA; high spatial resolution; landscape heterogeneity; topographic effects
Online: 27 February 2018 (03:22:59 CET)
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Karst rocky desertification (KRD) is a process where strong anthropogenic disturbances and exposure of carbonate bedrock occurs in fragile karst ecosystems. The fractional cover of rocky outcrops is a key indicator and mechanistic driver of KRD and can be accurately assessed using remote sensing technology. Nevertheless, rugged karst terrain relief can cause shadow effects on satellite imagery and combine with high heterogeneity of karst landscapes to prevent fractional cover retrievals. In this study, we explored the feasibility of applying multispectral high spatial resolution ALOS imagery for fractional cover extraction of rocky outcrops. We selected the dimidiate pixel model (DPM), which has been applied in previous studies, and spectral mixture analysis (SMA; including simple endmember spectral mixture analysis (SESMA) and multiple endmember spectral mixture analysis (MESMA)) to explore the feasibility of using remote images for KRD monitoring and improve accuracy for estimating fractions. Results from MESMA achieved high overall accuracy (76.4%) in monitoring percentage of rocky outcrop fraction in the study area. SESMA appears to underestimate percentage of rocky outcrop likely because the development of KRD was driven by complex factors (soil erosion, dissolution and anthropogenic disturbances). This results in spectral reflectance of rocky outcrop being variable in different settings. Predicted exposed bedrock coverage using SESMA and MESMA was similar in sun-lit and shaded areas although predictions from SESMA were smaller than reference data. DPM underestimated the fractional cover of rocky outcrops on south-facing slopes and overestimated it in shaded areas. Furthermore, SESMA and MESMA effectively reduced topographic effects. We conclude that it is better to extract percentage of rocky outcrop using MESMA in the karst region of southwestern China. Remote sensing is emerging as a feasible method to extract surface condition information in heterogeneous and rugged landscapes.
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Earth Sciences, Environmental Sciences; Fe- and Mg-rich smectite; alkaline; ophiolite; M-S-H; F-S-H; C-S-H; geological disposal; natural analogue; Mars
Online: 16 February 2018 (15:30:00 CET)
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Formation of Fe- and Mg-rich smectite and zeolite under alkaline conditions is concerned as secondary minerals after alkaline alteration of bentonite in a repository of radioactive wastes. It might be crucial for safety assessment whether smectite will be formed or not as secondary minerals after alkaline alteration of bentonite. In present paper, Fe- and Mg-rich smectite which are currently interacting with hyperalkaline groundwater was found at Narra in Palawan, Philippines. Mineralogical and geochemical investigation was conducted to understand formation process of smectite and factors determined secondary mineral species. Our study revealed a certain amount of smectite may have been produced under hyperalkaline conditions, altered from amorphous or poorly crystalline material such as M-S-H and F-S-H. Key factor which decides smectite or zeolite as secondary minerals after alkaline alteration of bentonite might be whether nuclei of M-S-H and/or F-S-H will be formed or not. This might be decided by the presence of dissolved Mg2+ and Fe2+ in the system. Our suggested formation process of smectite under alkaline conditions is analogue with generally-accepted model of smectite formation that might have been occurred on early Mars.
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Earth Sciences, Environmental Sciences; building damage; climate change scenarios; decision tree analysis; limit value; natural disaster; random forest; risk assessment process; South Korea
Online: 12 February 2018 (11:13:37 CET)
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Changes in extreme weather patterns are expected under climate change. In this study, a risk assessment was conducted using 4 building damage history datasets and 33 weather datasets (precipitation, wind speed, snow, and temperature) from 230 regions in South Korea to quantitatively analyze and predict building damage caused by potential future natural disasters. Decision tree analysis was used to evaluate building damage risk in 230 regions. The decision tree model to determine the risk of flood, gale, and typhoon was generated, which excluded gales, with less damage. The weight (variable importance) and limit value (damage limit) of the weather variables ware derived using the decision tree model. Using these two factors, we assessed the building damage risk in 230 regions in South Korea until 2100. The number of regions at risk of flood damage increased by more than 30% in average. Conversely, regions at risk of snowfall damage decreased by more than 90%. The regions at risk of typhoons decreased by 57.5% on average, and the number of regions at high risk of typhoon damage increased by up to 62.5% in RCP 8.5. These results can be used as objective data to minimize future building damage throughout South Korea, representing the first step towards sustainable development in the region with respect to disaster response.
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Earth Sciences, Environmental Sciences; microbial sulphide oxidation, corrosion, mine waste and water remediation, biofilm development, inhibition of Acid mine and rock draiange
Online: 8 February 2018 (15:35:56 CET)
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Abstract: Measures to counteract AMD generation need to start at the mineral surface, inhibiting mineral-oxidizing, acidophilic microbes. Laboratory and long-term field tests with pyrite-containing mining wastes, where Carbonaceous Phosphate Mining Waste (CPMW) was added, resulted in low acidity, and near neutral drainage. The effect was reproducible, nd confirmed by several independent research groups. This was shown to involve an organic coating, likely a biofilm. The biofilm formation was confirmed when CPMW was added to lignite coal waste with an initial pH of 1. Forty five days after the addition, the coal waste was dominated by heterotrophic microorganisms in biofilms. A review of the scientific literature supports that CPMW has physical and chemical characteristics which are capable of inducing a strong inhibitory effect on sulphide oxidation by forming an organic coating over the mineral surface. CPMW characteristics appear to provide the cornerstone of a new technology for the reduction of sulphide oxidation in mine wastes. An hypothesis for testing this technology is presented which could result in an economical and sustainable approach to mine waste and water management.
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Earth Sciences, Environmental Sciences; resource efficiency; zero waste; resource recovery from waste; low-carbon economy; circular economy infrastructure; clean growth; resource productivity; sustainable development goals; transdisciplinary research; participatory action research
Online: 5 February 2018 (03:27:02 CET)
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The UK economy is overly reliant on unsustainable production and consumption practices, depleting finite resources at rates that will increase production costs, business risk and economic instability. This over-consumption produces emissions and waste that cause climate change and environmental degradation, impacting on the wellbeing of people in the UK and beyond. The Resource Recovery from Waste programme (RRfW) promotes a transition towards waste and resource management in a circular economy that restores the environment, creates societal benefits and promotes clean growth by engaging relevant actors in the transition process. RRfW collaborates with academia, government, and industry to co-produce a shared vision and approach to realise such a transition. Reflecting insights from RRfW’s government engagement, this article presents a positive outlook for changing the UK economy and society. It envisions a long-term future for waste and resource management that maximises the value of materials by circulating them in the economy for as long as possible. Four themes and an approach are proposed, including recommendations for regulatory instruments and a stable policy framework. It recommends further collaborative research to capitalise on opportunities for economic growth, innovation and resilient infrastructure whilst contributing to quality jobs and welfare in all four UK nations.
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Earth Sciences, Environmental Sciences; ground water; pit latrines; fecal contamination; common factors
Online: 2 February 2018 (09:06:10 CET)
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The coastal dry zone areas of Sri Lanka mostly rely on ground water as the potable drinking water source because pipe born water is rarely provided. Most of the domestic units construct dug wells adjacent to houses where the ground water is exposed to fecal contamination due to pit – latrines. There available standards and commonly accepted factors regulating the construction of ground water extraction sources yet there is lack of evidence whether following them effectively prevent ground water fecal contamination. This research focus on applicability of commonly accepted factors on preventing the pit latrines correlated ground water contamination, taking twenty (20) sampling locations of Kalpitiya Peninsula of Sri Lanka as the case study area. The ground water was tested for Total coliform bacteria at 37 °C and E.Coil at 44 °C to identify the water quality level related to fecal contamination. The depth of water table, gap of infiltration layer, depth of latrine pit and distance between dug well and latrine pit were identified as the most commonly considered factors. Accordingly, case specific and area specific reasons apart from the ‘commonly accepted factors’ are highly influencing the pit latrines correlated ground water contamination in Kalpitiya Peninsula, Sri Lanka.
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Earth Sciences, Environmental Sciences; different sampling scales; spatial distribution; stony desertification characteristics; Karst; small watershed
Online: 30 January 2018 (13:19:46 CET)
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In this paper, the spatial distribution of stony desertification characteristics and its influencing factors in Karst areas in different sampling scales are studied using a grid sampling method based on geographic information system (GIS) technology and geo-statistics, with the rock bareness rate obtained through sampling with 150m × 150m grids in the Houzhai River Basin being taken as the original data and five grid scales (300m × 300m, 450m × 450m, 600m × 600m, 750m × 750m, and 900m × 900m) as the subsample sets. The results show that the rock bareness rate does not vary much from one sampling scale to another while average values of the five sub-samples all fluctuate around the average value of the entire set. As the sampling scale is expanding, the maximum value and the average value of rock bareness rate are decreasing gradually, with a gradual increase in the coefficient of variability. In the scale of 150m × 150m, the areas of minor stony desertification, medium stony desertification, and major stony desertification in the Houzhai River Basin are 7.81 km2, 4.50 km2, and 1.87 km2, respectively. The spatial variability of stony desertification on small scales is influenced by many factors, and that on medium scales is jointly influenced by gradient, rock contents, and rock bareness rate. On large scales, the spatial variability of stony desertification is mainly influenced by soil thickness and rock bareness rate.
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Earth Sciences, Environmental Sciences; forest biomass; aboveground biomass; airborne lidar; monitoring; regional forest inventory; variable selection; Bayesian model averaging; multiple linear regression
Online: 30 January 2018 (04:05:36 CET)
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Historical forest management practices in the southwestern US have left forests prone to high intensity, stand-replacement fires. Effective management to reduce the cost and impact of forest-fire management and allow fires to burn freely without negative impact depends on detailed knowledge of stand composition, in particular, above-ground biomass (AGB). Lidar-based modeling techniques provide opportunities to reduce costs and increase ability of managers to monitor AGB and other forest metrics. Using Bayesian Model Averaging (BMA), we develop a regionally applicable lidar-based statistical model for Ponderosa pine and mixed conifer forest systems of the southwestern USA, using previously collected field data. The selected regional model includes a mid and low canopy height metric, a canopy cover, and height distribution term. It explains 72% of the variability in field estimates of AGB, and the RMSE of the two independent validation data sets are 23.25 and 32.82 Mg/ha. The regional model developed is structured in accordance with previously described models fit to local data, and performs equivalently to models designed for smaller scale application. Developing regional models for broad scale application provides a cost-effective, robust approach for managers to monitor and plan adaptively at the landscape scale.
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Earth Sciences, Environmental Sciences; local activities, regional products, sustainability support
Online: 26 January 2018 (16:19:26 CET)
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Regional product labeling can help develop regional business activities, especially with traditional regional products. Their general popularity is a significant source of income for the less developed regions. The Gemer-Malohont region belongs to economically underdeveloped areas with high unemployment rate. The subject of the survey was regional food products, which are made by small farmer. The analysis was carried out on a questionnaire survey in the period April-July 2017 in each of the region's districts. The results obtained by questionnaire survey have been statistically processed using the statistical method (two-step cluster analysis, radar chart, box-plots, regression analysis) using Microsoft Excel and IBM SPSS Statistics 23 software. Through cluster analysis and based on the preference of regional food, we divided consumers into two groups - knowledgeable regional food purchasers and priced oriented consumers. We have shown that the more developed regions (Rimavská Sobota, Rožňava) show a higher rate of purchase of regional foods. Less developed regions (Poltár, Revúca) are represented by lower-income consumers for whose the food price is the decisive criterion. Local residents of backward regions should pay attention to domestic food and local small farmers, who are the way to create local capital and local development.
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Earth Sciences, Environmental Sciences; drought; diversity; oaks; remote sensing
Online: 26 January 2018 (04:52:27 CET)
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Drought periods have an adverse impact on the condition of oak stands. Research on different types of ecosystems has confirmed a correlation between plant species diversity and the adverse effects of droughts. The purpose of this study was to investigate the changes which occurred in an oak stand (Krotoszyn Plateau, Poland) under the impact of the summer drought in 2015. We used a method based on remote sensing indices from satellite images in order to detect changes in the vegetation in 2014 and 2015. A positive difference was interpreted as an improvement, whereas a negative one was treated as a deterioration of the stand condition. The Shannon-Wiener species diversity was estimated using an iterative PCA algorithm based on aerial images. We observed a relationship between the species indices of the individual forest divisions and their response to drought. The highest correlation between the index differences and the Shannon-Wiener indices was found for the GNDVI index (+0.74). In addition, correlations were observed between the mean index difference and the percentage shares in the forest divisions of species such as Pinus sylvestris (+0.67 ± 0.08) and Quercus robur (-0.65 ± 0.10). Our results lead us to infer that forest management based on highly diverse habitats is more suitable to meet the challenges in the context of global climatic changes, characterized by increasingly frequent droughts.
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Earth Sciences, Environmental Sciences; vegetation indices; LANDSAT; WorldView-2; RapidEye; AVIRIS
Online: 25 January 2018 (04:37:02 CET)
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Oil spills from offshore drilling and coastal refineries often cause degradation of coastal wetlands that can take a long time to recover. Early oil detection may prevent losses and speed up recovery if monitoring of the initial oil extent, oil impact, and recovery are in place. Satellite imagery data can provide a cost-effective alternative to expensive airborne imagery or labor intensive field campaigns for monitoring effects of oil spills on wetlands. However, these satellite data may be restricted in their ability to detect and map ecosystem recovery post-spill given their spectral measurement properties and temporal frequency. In this study, we assessed whether spatial and spectral resolution, and other sensor characteristics influence the ability to detect and map vegetation stress and die-off due to oil. We compared how well three satellite multispectral sensors: WorldView2, RapidEye and Landsat EMT+, match the ability of the airborne hyperspectral AVIRIS sensor to map oil-induced vegetation stress, recovery, and die-off after the DeepWater Horizon oil spill in the Gulf of Mexico in 2010. We found that finer spatial resolution (3.5m) provided better delineation of the oil-impacted wetlands and better detection of vegetation stress along oiled shorelines in saltmarsh wetland ecosystems. As spatial resolution become coarser (3.5m to 30m) the ability to accurately detect and map stressed vegetation decreased. Spectral resolution did improve the detection and mapping of oil-impacted wetlands but less strongly than spatial resolution, suggesting that broad-band data may be sufficient to detect and map oil-impacted wetlands. AVIRIS narrow-band data performs better detecting vegetation stress, followed by WorldView2, RapidEye and then Landsat 15m (pan sharpened) data. Higher quality sensor optics and higher signal-to-noise ratio (SNR) may also improve detection and mapping of oil-impacted wetlands; we found that resampled coarser resolution AVIRIS data with higher SNR performed better than either of the three satellite sensors. The ability to acquire imagery during certain times (midday, low tide, etc.) or a certain date is also important in these tidal wetlands; WorldView2 imagery captured at high-tide detected a narrower band of shoreline affected by oil likely because some of the impacted wetland was below the tideline. These results suggest that while multispectral data may be sufficient for detecting the extent of oil-impacted wetlands, high spectral and spatial resolution, high-quality sensor characteristics, and the ability to control time of image acquisition may improve assessment and monitoring of vegetation stress and recovery post oil spills.
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Earth Sciences, Environmental Sciences; crop residues; water regime; crop rotation; temperate region
Online: 17 January 2018 (13:00:39 CET)
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This study was carried out at Kita-mura near Bibai located in central Hokkaido, Japan, with the intention of investigating the effects of different agronomical managements on CH4 emissions from paddy fields on mineral soil over peat under farmers’ actual management conditions in the snowy temperate region. Four fields were studied, including two fields with twice drainage (D1-M and D2-M) and also a single-drainage field (D3-S) under single-cropping yr-1 and a paddy-fallow-paddy crop rotation as their systems. The other field was under single cropping yr-1 with continuous flooding (CF-R) in the pattern of soybean (upland crop)-fallow-paddy. The mineral-soil thickness of these soil-dressed peatland fields varied from 20 to 47 cm. The amount of crop residues leftover in the fields ranged from 277 to 751 g dry matter m−2. Total CH4 emissions ranged from 25.3 to 116 g CH4-C m−2 per growing season. There was a significant relationship between crop-residue carbon (C) and total CH4 emissions during the rice-growing season. This study, therefore, CH4 fluxes from paddy soils in that there was a strong interaction between readily available C source for methanogens and anaerobic conditions created by water management. Despite the differences in water regime and soil type, the average values of straw’s efficiency on CH4 production in this study were significantly higher than those of southern Japan and statistically identical with central Hokkaido. Our results suggest that the environmental conditions of central Hokkaido in association with crop-residue management had a significant influence on CH4 emission from paddy fields on mineral soil over peat. Rotation soybean (upland)-to-paddy followed by drainage twice practices also largely reduces CH4 emission. However, mineral-soil dressing on peat could have a significant impact to suppress CH4 emission from beneath the peat reservoir.
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Earth Sciences, Environmental Sciences; Epithermal; Kerogen; Pyrite; Pyro-Bitumen; Thallium; Volcanogenic sulfide mineralization.
Online: 17 January 2018 (11:48:52 CET)
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Hydrothermal pyrite is an important source of thallium (Tl) but this rare element can be also detected in the secondary iron goethite-lepidocrocite and jarosite ores, associated to hydrothermal kerogen, manganese oxides, accessorial potassium minerals and tiny Tl-bearing clusters shielded in quartz masses. We studied Tl-bearing samples collected from Fe-Mn ores hosted in dolostone rocks sited along ca. 15 km of fossil thermal springs following a geological fault in the Lodares surroundings. Samples were analyzed by environmental scanning electron microscopy and energy dispersive spectroscopy (ESEM-EDS), electron probe micro-analysis (EPMA), inductively coupled plasma-mass spectroscopy (ICP-MS), X-ray diffraction analysis (XRD), Tl LIII-edge X-ray absorption near-edge structure (XANES) spectroscopy, Micro-Raman and Fourier transform infrared spectroscopy (FTIR). We found epithermal pyrite, sphalerite, galena and baryte and secondary gypsum, jarosite, scorodite, anglesite, goethite, epsomite and elemental sulfur produced by both hydroxylation and bacterial processes. The highest Tl contents were found in hydrothermal pyrite (200 mg kg-1), kerogen (13 mg kg-1), manganese ores (27 mg kg-1) and iron sulfate-hydroxides (142 mg kg-1). The aquatic kerogen was formed in a marine environment and later heavily carbonized during the hydrothermal processes. The Lodares outcrops exhibit interesting details on the geochemical cycle of Tl in a genetic frame of epithermal formation of pyrite and kerogen.
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Earth Sciences, Environmental Sciences; climate change; GR2M; hydrologic modeling; transboundary river; West Africa
Online: 17 January 2018 (11:09:07 CET)
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In the context of climate change in West Africa characterized by a reduction of precipitation, this study was conducted to evaluate the impact of climate change on water resources from now to the end of the 21st century in the transboundary watershed of the Sassandra River shared by Guinea and Côte d’Ivoire. Historical and future climate (Representative Concentration Pathways or RCPs 4.5 and 8.5 scenarios) data were projected with the model. The Abdus Salam ICTP RegCM4 was used. The hydrological modeling of the river basin was carried out with the conceptual hydrological model, GR2M. This model is a monthly time steps model that allows the assessment of the discharge of the Sassandra River for each climate scenario according to the 2030 (2021–2040), 2050 (2041–2060), 2070 (2061–2080), and 2090 (2081–2100) horizons. The results showed a reduction of the annual discharge when compared to the baseline (1961–1980). For the RCP 4.5, the observed values went from –1.2% in 2030 to –2.3% in 2070 and rose to –2.1% in 2090. Concerning the RCP 8.5, we saw a variation from –4.2% to –7.9% in the 2030 and 2090 horizons, respectively. With the general decrease of rainfall in West Africa, it is appropriate to assess the impact on water resources on the largest rivers (Niger, Gambia, and Senegal) that irrigate the Sahelo-Saharian zone.
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Earth Sciences, Environmental Sciences; water quality indices; spatio-temporal analysis; ébrié lagoon; surface water; Abidjan
Online: 17 January 2018 (07:54:12 CET)
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For decades, the Ébrié Lagoon in Côte d'Ivoire has been the receptacle of wastewater effluent and household waste transported by runoff water. This work assesses the spatio-temporal variability of the Ébrié lagoon water quality at the city of Abidjan. The methodological approach used in this study is summarized in three stages: the choice and standardization of the parameters for assessing water quality for uses such as aquaculture, irrigation, watering, and sports and recreation; the weighting of these parameters using the Hierarchical Analysis Process (AHP) of Saaty; and finally, the aggregation of the weighted parameters or factors. Physicochemical and microbiological analysis data on the waters of the Ébrié lagoon for June and December of 2014 and 2015 were provided by the Ivorian Center for Anti-Pollution (Centre Ivoirien Anti-Pollution, CIAPOL) and the concentrations of trace elements in sediments (As, Cd, Cr, Pb, Zn) were used. The aggregation of standardized and weighted parameters allowed the determination of the Water Quality Indices (WQI) by usage for each bays of the lagoon. The results show that in both 2014 and 2015, the waters of the Ébrié lagoon were generally of poor quality for the different uses examined in this study (aquaculture, irrigation, watering and sport and recreation) with an accentuation in 2015. However, some bays of the lagoon have waters of dubious to satisfactory quality. This study contributes an improved evaluation of the Ébrié lagoon waters.
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Earth Sciences, Environmental Sciences; water level measurement; surface hydrology; unmanned aerial vehicle; drone; dam
Online: 10 January 2018 (17:48:03 CET)
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Unmanned Aerial Vehicles (UAVs) are now filling in the gaps between spaceborne and ground-based observations and enhancing the spatial resolution and temporal coverage of data acquisition. In the realm of hydrological observations, UAVs have a key role to quantitatively characterize the surface flow allowing for remotely accessing the water body of interest. In this paper we propose a technology which uses a sensing platform encompassing a drone and a camera to determine the water level. The images acquired my means of the sensing platform are then analyzed using the Canny method to detect the edges of water level and of Ground Control Points (GCPs) used as reference points. The water level is then retrieved from images and compared to a benchmark value obtained by a traditional device. The method is tested at four locations in an artificial lake in central Italy. Results are encouraging as the overall mean error between estimated and true water level values is around 0.02 m. This technology is well suited to improve hydraulic modeling and thus provide a reliable support to flood mitigation strategies also in uneasy-to-access environments.
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Earth Sciences, Environmental Sciences; particulate matter; AOD; planetary vertical corrections; humidity corrections
Online: 10 January 2018 (03:16:02 CET)
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Satellite-based monitoring can retrieve ground-level PM2.5 concentrations with higher-resolution and continuous spatial coverage to assist in making management strategies and estimating health exposures. The Sichuan Basin has a complex terrain and several city clusters that differ from other regions in China: it has an enclosed air basin with a unique planetary boundary layer dynamic which accumulates air pollution. The spatiotemporal distribution of 1-km resolution Aerosol Optical Depth (AOD) in the Sichuan Basin was retrieved using the improved dark pixel method and Moderate Resolution Imaging Spectroradiometer (MODIS) data in this study. The retrieved seasonal AOD reached its highest values in spring and had the lowest values in autumn. The higher correlation (r = 0.84, N = 171) between the ground-based Lidar AOD and 1-km resolution MODIS AOD indicated that the high-resolution MODIS AOD could be used to retrieve the ground-level PM2.5 concentration. The Lidar-measured annual average extinction coefficient increased linearly with the Planetary Boundary Layer Height (PBLH) in the range of 100 ~ 670 m, but exponentially decreased between the heights of 670 ~ 1800 m. Both the correlation and the variation tendency of simulated PBLH from WRF_SHIN/CALMET were closer to the Lidar observation than that of three other Planetary Boundary Layer (PBL) schemes (the Grenier-Bretherton-McCaa (GBM) scheme, the he Total Energy-Mass Flux (TEMF) scheme and the University of Washington (UW) scheme), which suggested that the simulated PBLH could be used in the vertical correction of retrieval PM2.5. Four seasonal fitting functions were also obtained for further humidity correction. The correlation coefficient between the aerosol extinction coefficient and the fitted surface-level PM2.5 concentration at the benchmark station of Southwest Jiao-tong University was enhanced significantly from 0.62 to 0.76 after vertical and humidity corrections during a whole year. During the evaluation of the retrieved ground-level PM2.5 with observed values from three cities, Yibin (YB), Dazhou (DZ), and Deyang (DY), our algorithm performed well, resulting in higher correlation coefficients of 0.78 (N = 177), 0.77 (N = 178), and 0.81 (N = 181), respectively.
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Earth Sciences, Environmental Sciences; continental climate; exceptional floods; historic discharge; hydro-technical works; material damage; Siret catchment basin; NE Romania
Online: 9 January 2018 (08:38:52 CET)
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The Siret River crosses NE Romania from the north to the south and it discharges into the Danube, near the city of Galati. During the period, 17th June - 10th July 2010, significant amounts of precipitations in the mountainous basin of Siret were recorded. The floods comprised two periods with four bimodal cycles and they were counted among the strongest on the Romanian territory. The exceptional floods occurred in the rivers of Siret, Suceava, Moldova, Bistrita, Trotus and so on. The most important compound flood wave was determined by the precipitations which fell within the period, 29th June to 1st July 2010, when significant amounts of rain were recorded, sometimes, exceeding 80 mm. The high discharges on the Bistrita River – downstream from the Bicaz Reservoir – were controlled by complex hydro technical works. The maximum discharge for the year 2010 summer floods was recorded at Dragesti hydrometric station: 2,884 m3/s (historic discharge) compared to the preceding historic discharge of the year 2008 (2,850 m3/s). The effects of floods were strongest in the counties of Suceava, Neamt, and Bacau. The floods on the main course of the Siret River were analyzed in correlation with the tributaries within the mountainous sector.
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Earth Sciences, Environmental Sciences; water scarcity; watershed restoration; land use distribution; soil type; curve number; Zarqa River’s flow simulation; end-users
Online: 8 January 2018 (09:59:13 CET)
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The heavy demand of water resources from the Zarqa River Basin (ZRB) has resulted in a base-flow reduction of the River from 5m3/s to less than 1m3/s. This paper aims at predicting Curve Numbers (CN) as a baseline scenario and proposing restoration scenarios for ZRB. The method includes classifying the soil type and land use, predicting CNs, and proposing CN restoration scenarios. Prediction of existing CNs will be in parallel with the runoff prediction using the US Army Corps of Engineers HEC-1 Model, and Rainfall-Runoff Model (RRM). The models have been set up at the land use distribution of 0.3% water body, 9.3% forest and orchard, 71% mixture of grass, weeds, and desert shrubs, 7.0% crops, 4.0% urban areas, and 8.4% bare soil. The results show that CN under dry condition are 59, 78 under a normal condition and 89 under a wet condition. During vegetation period, CN are 52, 72 and 86 for the dry, normal and wet condition respectively. The restoration scenarios; CN decreases runoff, and increases soil moisture when using the contours, terraces and crop residues. Analyzing results of CN scenarios will be a fundamental tool to support end-users related to their targets to achieve watershed restoration.
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Earth Sciences, Environmental Sciences; freezing/melting desalination process; aqueous solutions of sodium chloride; theoretical diffusive models
Online: 4 January 2018 (07:08:51 CET)
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Considering the important demand of fresh water and its scarce availability, water desalination is an interesting technology, producing about 44 Mm3/year worldwide, but, in general the most common desalination techniques are highly energy demanding. Freezing-Melting (F/M) desalination uses just up to 70% less thermal energy, but is the least used process mainly, due to the difficulty of the salt separation. This study proposes a model able to analyses the thermodynamic potential that allows the salt diffusion during the F/M process, using an aqueous solution of sodium chloride. This should allow to obtain a sensitive analysis of the process to promote the separation between the high concentration brine and the ice with liquid separation by physical process. The unidimensional model is based on the evolution of both processes: thermal and mass diffusions, depending on temperature and saline gradients, predicting whether the salt will remain inside the ice or not. Thus, the thermal potential is adjusted to frozen only when the salt has been "pushed" towards the brine. Mostly models have base their results on the assumption of a “certain value of saline concentration of the liquid fraction”, value in which there is great disagreement. In this paper the calculations are based on the concentration in the solid-liquid interface, which has been extensively studied and there is a coincidence in those results, being the main advantage of the proposed model.
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Earth Sciences, Environmental Sciences; algal pigment; fossil diatom; sediment core, climate change
Online: 2 January 2018 (12:13:28 CET)
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The overarching aim of this paper is to investigate the lake ecosystem response to different drivers over a long term period by a paleolimnological study in Lake Narlay (46°64N, 5°91E) located in the Jura Mountains of France. It is a small, hard-water lake with a maximum water depth of 40 m and extended anoxic condition of the bottom water. Previous results on sediments analysis have documented a differential response of the lake to the environmental changes that occurred in AD 1600 when major shift in the trophic reliance on methane of the benthic food web were observed. From 1920 with intensification of modern agriculture, animal farming and the construction of a cheese making facility, the lake become eutrophic, with Oscillatoria rubescens bloom. However, the lake showed pronounced changes in an older period that remained unanswered. In this paper we aim at reconstructing in more detail the limnological conditions of this Lake over the last 1200 yrs. using combined analyses of specific algal carotenoids and subfossil diatom remains. A comparison with other proxies (chironomid, pollen, and instrumental climatic reconstruction) will be used to better identify, between the complex combination of climate and anthropogenic pressure, the driving factors that determined the ecological trajectory of Lake Narlay.
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Earth Sciences, Environmental Sciences; non-freezing; temperate lake; heat budget; heat storage; global warming
Online: 2 January 2018 (08:17:58 CET)
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A temperate deep lake, Lake Kuttara, Hokkaido, Japan (148 m deep at maximum) was completely frozen every winter in the 20th century. However, unfrozen conditions of the lake over winter occurred four times in the 21st century, which is probably due to global warming. In order to understand how thermal regime of the lake responds to climate change, its heat storage change was calculated by estimating heat budget of the lake and monitoring water temperature at the deepest point for September 2012–June 2016. As a result, temporal change of the heat storage from the heat budget was very consistent with that from the direct temperature measurement (determination coefficient R2 = 0.827). The 1978–2017 data at a meteorological station near Kuttara indicated that there are significant (less than 5% level) long-term trends for air temperature (0.024 °C/yr) and wind speed (−0.010 m/s/yr). A sensitivity analysis for the heat storage from the heat budget estimate and an estimate of return periods for mean air temperature in mid-winter allow us to conclude that the lake could be unfrozen once per about two year in a decade.
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Earth Sciences, Environmental Sciences; SLEUTH model; Sensitivity Analysis; uncertainty assessment; urban expansion.
Online: 27 December 2017 (02:40:27 CET)
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SLEUTH Model (slope, landuse, exclusion, urban extent, transportation and hillshade) is an important tool for landuse planning and land policy. To evaluate the performance of SLEUTH model, implementation of Sensitivity Analysis (SA) is essential. The main limitation of SA in SLEUTH application is a lack of insight into model input self-modification parameters (SMPs) variation, namely, uncertainty involved in the model transfer metrics and model presumptions, which often misled the decision makers and model users. To address this issue, this study divided the forward process into two stages. Firstly, during the transfer process ①, the contribution scores of five SMPs were drawn, and parameters highly sensitive to model output were given. Apart from that, the recommended initial value for SMPs of 0.11, 0.2, 0.87, 1.13, 15, 1.01, 0.49 were found to be subordinated to such a heterogeneous urban area simulation. Secondly, during the transfer process ②, SMP caused imagery metrics indicated the disparity between parameters with Fixed Reference and with Successive Reference. Reversely, it derives reasonable threshold for the best fit values of five prediction coefficients’ initialization by comparing the real image with the predicted one. The framework of SLEUTH model transfer mechanism not only could distinguish highly sensitive SMPs with higher contribution scores, but also could give parametric analysis for simulation imagery based on metrics. The study was found to be a practical tool for quantization response of model input variables for modelling complex urban systems. So, this insight can help geographic information scientists decide how to find out the inner forward transfer mechanism of SLEUTH model for further make good use of it and improve the model.
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Earth Sciences, Environmental Sciences; wastewater recovery; innovative treatment technologies; electro-flotation; reverse logistics system
Online: 21 December 2017 (03:55:44 CET)
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Proper management of water is a challenge for every individual but especially for companies. Nowadays also legislation obliges companies to clean the wastewater before being discharged into municipal public sewer especially if they use some chemicals or oily elements in their production process. Construction of the wastewater cleaner depends directly on the way of pollution, the amount of contaminated water and the energy demand of the cleaning process. The paper deals with the construction of the wastewater cleaner, which is based on the technology of electro-flotation for the treatment of water contaminated with disperse colorants. The experimental work as well as the modelling using the statistical methods proved the suitability of the chosen technology. Also, each colour combination requires a specific time period for the water treatment. The authors determined the time interval for cleaning the wastewater that was polluted with yellow colour to 33 minutes. Finally, the wastewater cleaner that is based on the electro-flotation technology was included in the company’s reverse logistics system.
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Earth Sciences, Environmental Sciences; vulnerability index; Maasai pastoralists; principal component analysis; climate change
Online: 18 December 2017 (17:21:00 CET)
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Human adaptive responses to climate change occur at the local level, where climatic variability is experienced. Therefore analyzing vulnerability at the local level is important in planning effective adaptation options in a semi-arid environment. This study was conducted to assess vulnerability of Maasai pastoralist communities in Kajiado County, Kenya to climate change by generating vulnerability index for the communities. Data was collected using questionnaires that were administered to 305 households in the five different administrative wards (Oloosirkon/Sholinke, Kitengela, Kapetui North, Kenyawa-Poka and Ilmaroro) in Kajiado East. Vulnerability was measured as the net effect of adaptive capacity, sensitivity and exposure to climate change. Principal Component Analysis (PCA) was used to assign weights to the vulnerability indicators used for the study and also to calculate the household vulnerability index. A vulnerability map was produced using the GIS software package ArcGIS 10.2. Results showed that gender of household head, age of household head, educational level, access to extension agents, herd size, livestock diversity and access to credit facility influenced vulnerability of the Maasai pastoralists to climate change in Kajiado East. The result showed that the most vulnerable communities with the highest negative vulnerability index value are Ilpolosat (-2.31), Oloosirikon (-2.22), Lenihani (-2.05), Konza (-1.81) and Oloshaiki (-1.53). The communities with the highest positive vulnerability index values were Kekayaya (4.02), Kepiro (3.47), Omoyi (2.81), Esilanke (2.23), Kisaju (2.16) and Olmerui (2.15). We conclude that provision of basic amenities such as good roads and electricity; access to extension agents, access to credit facilities and herd mobility will reduce vulnerability of Maasai pastoralists in Kajiado east to climate change and variability.