ARTICLE | doi:10.20944/preprints201911.0324.v1
Subject: Engineering, Energy & Fuel Technology Keywords: water–energy nexus; energy use; energy intensity
Online: 27 November 2019 (03:44:36 CET)
The water and wastewater sectors are energy-intensive, and so a growing number of utility companies are seeking to identify opportunities to reduce energy use. Though England’s water sector is of international interest, in particular due to the early experience with privatisation, for the time being very little published data on energy usage exists. We analyse telemetry data from Thames Water Utilities Ltd. (TWUL), which is the largest water and wastewater company in the UK and serves one of the largest mega-cities in the world, London. In our analysis, we (1) break down sectoral energy use into their components, (2) present a statistical method to analyse the long-term trends in use, as well as the seasonality and irregular effects in the data, (3) derive energy-intensity (kWh m3) figures for the system, and (4) compare the energy-intensity of the network against other regions in the world. Our results show that electricity use grew during the period 2009 to 2014 due to capacity expansions to deal with growing water demand and storm water flooding. The energy-intensity of the system is within the range of reported figures for systems in other OECD countries. Plans to improve the efficiency of the system could yield benefits in lower the energy-intensity, but the overall energy saving would be temporary as external pressures from population and climate change are driving up water and energy use.
ARTICLE | doi:10.20944/preprints201810.0734.v1
Subject: Engineering, General Engineering Keywords: wind energy; weibull distributions; water abstraction; water stress; water pumping
Online: 31 October 2018 (06:54:36 CET)
Wind energy powered pumps could be an alternative to conventional fuel powered pumps for water abstraction because they rely on a free energy and they are environmentally friendly. The objective of this study was to assess the potential of wind energy to operate water abstraction systems in Teso sub-region of Uganda for livestock watering Daily mean wind speeds recorded at a height of 10 m for a period of ten years (2005–2015) were collected from Amuria and Soroti Meteorological stations in the study area. Data were analyzed using Weibull distribution to evaluate the annual wind speed frequency distributions and consequently assess their potential for water abstraction. The results indicated that warmer months (January, February and March) have higher mean wind speeds than the cold months (August, September and October). High wind speeds in the dry seasons corresponded to the periods of high water demand. The highest shape parameter (k) of 3.07 was registered in 2009 and scale parameter (c) of 3.78 in 2012. The highest wind power density of 43 W/m2 was obtained the year 2012 while the lowest wind power density of 15.47 W/m2 was obtained for Soroti district in the year 2009. The maximum power extractable in Amuria in 2012 was 324 W/m2 which is potentially enough for water abstraction. Maximum discharges of 1.86 m3/s and 1.52 m3/s were obtained for Amuria and Soroti districts respectively at mean wind speeds of 5 m/s. Therefore, Teso sub region winds have potential for water abstraction and Amuria district better sites for livestock watering using wind energy.
ARTICLE | doi:10.20944/preprints201902.0086.v1
Subject: Engineering, Civil Engineering Keywords: hydro-power; hydro-power plant; micro-energy; renewable energy; water energy
Online: 11 February 2019 (09:05:34 CET)
The conceptual reconstruction of Neiwan powerhouse is one of the key activities under the current ongoing mapping project of Taiwanese hydropower plants that mainly took place between 2013 and 2015 and is now focused on micro, pico, and historical power plants. Judging from the fact that the oldest hydropower plant in Taiwan named Guishan starts its operation in 1905, Neiwan powerhouse was among the very first powerhouses that were built across the island to support the electrification of Taiwan. However, the main function of the single turbine equipped Neiwan micro powerhouse was to support mainly the military needs and protect the territories occupied by Japanese troops. Since the powerhouse was built in 1909 and operates only something about 10 year there are very little physical materials or evidence along with contemporaries. Therefore the further reconstruction is based mainly on physical observation of the remains located at the site, old photographs, related articles, treatises and typology of mechanical and civil constructions of other hydropower plant cases in Taiwan hence this paper´s main intention is to pitch a concept reconstruction rather than definite conclusion.
ARTICLE | doi:10.20944/preprints201812.0127.v1
Subject: Engineering, Energy & Fuel Technology Keywords: hydro-power; hydro-power plant; micro-energy; renewable energy; water energy
Online: 11 December 2018 (10:46:08 CET)
This research paper is part of the wider project concerning the very first detailed mapping of the overall Taiwanese hydro-power plants that took place from 2013 up to 2015 and it is currently in evaluation and finalization stage. The case of Shanping hydro-power plant has been carefully studied, photographed, documented and mapped in situ. It was one of the isolated hydro-power plant projects originally built to supply the remote area with the specific designation. Shanping hydro-power plant, as well as the other units from the early hydro-power generation era in Taiwan, are considered to be the technological heritage of civil and mechanical engineering that reflects later in all the further projects up to nowadays modern Taiwanese hydro-power plants. Unfortunately, most of the hydro-power houses from the older periods were severely damaged or destroyed by natural causes which were also the case of Shanping unit. The research is trying to reconstruct the original location of the powerhouse and its supporting structures based on available historical documents, previous studies, comparative methodology, and the current on-site observation.
ARTICLE | doi:10.20944/preprints201805.0369.v1
Subject: Engineering, Energy & Fuel Technology Keywords: energy efficiency; reservoir network; water supply
Online: 25 May 2018 (12:20:12 CEST)
The power generation from hydroelectric plants has increased worldwide, contributing to the participation of the renewable sources to the energy matrix. In the semiarid Brazilian Northeast (NEB), thousands of small dams have been built over time as a solution for water supply. Although incompatible with hydropower generation due to the conflict with human water supply in the region, small reservoirs accumulate water and hydraulic energy at high altitudes. In this work, simulations were performed to assess how the arrangement of various sized reservoirs impact the power demand for water distribution in the Banabuiú River Basin – BRB (19,800 km²), Brazil. The power required to pump water from all 1,405 reservoirs to the districts is 6.5 GWh/year, whereas in the scenario with the 12 larger strategic reservoirs only, the power demand reaches 45.3 GWh/year. Although representing roughly 60% of the water availability of the BRB and being able to supply all the districts, the Arrojado Lisboa reservoir alone would demand 195 GWh/year to supply water to the entire basin, i.e. 30 times the power required in the real reservoir arrangement. By storing water at high altitudes and distributing it spatially, the small reservoirs increase the energy efficiency on the water distribution system.
ARTICLE | doi:10.20944/preprints201709.0020.v1
Subject: Keywords: WEPS; district heating; water-thermal energy production system; fjords; water heating; external effects
Online: 7 September 2017 (03:38:00 CEST)
The purpose of this paper is to describe a new way of producing renewable energy based on fjords as a water heater. We will call this system the Water-thermal Energy Production System (WEPS), because the basic idea is to extract heating and cooling energy from water. Although a prototype of WEPS has existed in Norway for more than ten years, a WEPS currently in operation has not been financially analyzed in the literature. Coastal parts of Norway have a potential of 5 TWh of profitable WEPS-facilities , due to convenient access to fjords containing water with stable all-season temperatures of about 4–12C when the depth of the water is about 50 meters. This stability of the water temperature makes it possible to extract energy from the fjord in a very efficient way. The potential for economically-profitable WEPS in other parts of the world has not been estimated. In order to answer such a question, more research is required. We have conducted a case study of a WEPS located in the Norwegian municipality of Eid. This is the first full-scale Norwegian WEPS, and it has been operating since 2006. The nascent years have passed, and the technology has been in operation for some years. In this paper, we have made an estimate of the business profitability and the external effects based on past empirical evidence and some assumptions about future development in some key figures. The results suggests that WEPS-Eid has been a profitable investment carrying a positive internal rate of revenue, even if the present underutilization in production capacity will continue in the future. Stability in energy prices for heating purposes has also gained customers compared to the more volatile prices of alternative renewable energy, like hydropower or wind turbines. The negative, external effects in the operating phase from WEPS-Eid are insignificant. Despite the significant profitability of the WEPS facility in Eid, there are two main obstacles for new entrants. There is a lack of relevant operational information for potential investors due to few facilities. This leads to uncertainty, and investments in WEPS appear as a risky business. Secondly, construction of a WEPS requires both big financial investments in digging and facilitating long trenches for a pipeline system and time and effort spent on acquiring the licenses needed for doing this work. A coordinating unit is probably required in order to get the necessary public and private licenses and to reduce fixed costs by coordinating other tasks in the same trenches, like pipes for water and sewer, fiber cables and tele-cables. In Eid, the local municipal administration was the coordinating unit.
ARTICLE | doi:10.20944/preprints202003.0147.v1
Subject: Social Sciences, Other Keywords: Golden Triangle Energy Region; water resources; optical allocation
Online: 9 March 2020 (02:34:59 CET)
There are abundant coal, oil and natural gas resources in "Golden Triangle" energy region. Energy resources development, coal chemical industry, coal power and other industries play an important role in promoting regional economic growth, but facing the insufficient water supply. Under the condition of marginal equilibrium of water resources, the paper firstly analyzes the water utilization, and calculates the potential water-saving amount. Then, the paper constructs a cooperative game model and allocates the newly increased GDP by using the weight distribution method. Finally, the paper puts forward some policy suggestions to reduce the efficiency gap of water utilization among regions.
ARTICLE | doi:10.20944/preprints202007.0085.v1
Subject: Engineering, General Engineering Keywords: Floating PV system; Sustainable Energy Production; Solar Power Plant; Water Infrastructures; Evaporation; Water Conservation
Online: 5 July 2020 (15:34:45 CEST)
The issue of water and energy crisis have been turned into global matters which need to be tackled jointly. Accordingly, floating solar power plants, in which photovoltaic modules are used on the surface of water infrastructures, has recently been attracting much interest. This system provides some additional advantages over the ground-based system such as conserving the land and the water and increasing the efficiency of the module. This study first reviews the relevant literature comprehensively and then evaluates the potential of using floating solar photovoltaic (FSPV) on some of Iran’s water infrastructures which have experienced a large amount of evaporation every year due to high solar radiation. To this end, the five important dam reservoirs are selected as the representatives of the five important watersheds in Iran, and the advantages of the FSPV plant is analyzed in terms of energy generation, evaporation reduction, economic and environmental aspects considering different coverage percentages of reservoir’s surfaces. Considering Iran's vast potential for solar radiation, and, on the other hand, huge energy demand and critical water situation, results indicated that Iran can effectively harness solar energy through FSPV systems which help conserve the water in addition to support sustainable energy production.
Subject: Engineering, Civil Engineering Keywords: pressure control; micro-hydropower; energy recovery; Water distribution network; Banki turbine; energy harvesting
Online: 20 May 2019 (09:43:43 CEST)
Although many devices have recently been proposed for pressure regulation and energy harvesting in water distribution and transport networks, very few applications are still documented in the scientific literature. A new in-line Banki turbine with positive outflow pressure and a mobile regulating flap, named PRS, was installed and tested in a real water transport network for pressure and discharge regulation. The PRS turbine was directly connected to a 55 kW asynchronous generator with variable rotational velocity, coupled to an inverter. The start-up tests showed how automatic adjustment of the flap position and the impeller velocity variation are able to change the characteristic curve of the PRS according to the flow delivered by the water manager or to the pressure set-point assigned downstream or upstream of the system, still keeping good efficiency values in hydropower production.
ARTICLE | doi:10.20944/preprints201804.0146.v1
Subject: Biology, Ecology Keywords: species richness; latitudinal gradients; water-energy; habitat; animal richness
Online: 11 April 2018 (11:24:46 CEST)
Species data of 249 National Nature Reserves in China was used to identify potential underlying drivers of latitudinal gradients in plant diversity. We used generalized linear models (GLMs) to assess the correlations between predictor and response variables. We also used SAM (Spatial Analysis in Macroecology) to eliminate autocorrelation along each of the 249 studied locations. We used the Akaike information criterion (AICc; Montoya et al. 2007) to select the independent variables were those included in the best models from different combinations of climate, habitat and animal variables. Variance partitioning was used to decompose the variation in plant richness across different taxonomic levels among the three groups of predictors. We found that: Total plant species, gymnosperms, angiosperms and ferns showed significant latitudinal trends in richness (p < 0.001). Water-energy and habitat variables generally explained more variation in richness across different plant groups than did animal richness. Annual precipitation was selected as the best water-energy variable across different taxonomic plants groups, soil PH and elevation range were selected as the best habitat variables across different taxonomic plant groups. The independent effects of habitatvariables were higher than that of water-energy and animal variables across different taxonomic plants groups. Water-energy, habitat heterogeneity, and animal variables explain 48.8% of the variation in total species richness, 28.2% in gymnosperm richness, 44.2% in angiosperm richness, and 38.9% in fern richness.Plants showed significant latitudinal trends in richness (p < 0.001). Water-energy and habitat variables generally explained more variation in richness across different taxonomic plants groups than did animal variables. The independent effects of habitat variables were higher than those of water-energy and animal variables across different taxonomic plants groups.
ARTICLE | doi:10.20944/preprints201810.0197.v1
Subject: Earth Sciences, Environmental Sciences Keywords: water-energy nexus; MENA region; climate change; mitigation/adaptation strategies
Online: 10 October 2018 (03:59:07 CEST)
The present paper aims to elucidate the impact of climate change on the availability and security of water and energy in the Middle East and North Africa Region (MENA Region). The region is particularly challenged by a number of factors including a large variability of bio-geographical characteristics, extreme population growth over the last few decades and substantial societal and economical transitions as well as armed conflicts in some of the countries of the region. Anticipated changes in climate conditions will exacerbate the challenges with regard to providing sufficient amounts of water and energy to the communities in the region. Impacts of climate change will materialize as an increasing number of heat waves, primarily in urban structures and the decline in water availability as a result of enhanced droughts and a growing numbers of dry spells. The interrelationships between energy and water and their mutual dependencies are addressed by the Water-Energy-Nexus concept. With regard to the challenges addressed here, Cyprus and the Eastern Mediterranean are a particular point in case. Mitigation and adaptation strategies include enhanced efficiency of energy and water use, integrated technology assessments regarding electricity generation and the production of potable water and electricity through concentrated solar power.
ARTICLE | doi:10.20944/preprints202107.0284.v1
Subject: Chemistry, Analytical Chemistry Keywords: entropy; enthalpy; equilibrium; ergal; free energy; Gibbs energy; Haber process; Helmholtz energy; hydrogen dissociation; transition state; water dissociation; virial theorem
Online: 13 July 2021 (09:57:00 CEST)
Clausius’ virial theorem set a basis for relating kinetic energy in a body of independent material particles to its potential energy, pointing to their complementary role with respect to the second law of maximum entropy. In action mechanics, expressing the entropy of ideal gases as a capacity factor for sensible heat or enthalpy plus the configurational work to sustain the relative translational, rotational and vibrational action yields algorithms for estimating chemical reaction rates and positions of equilibrium. All properties of state including entropy, work potential as Helmholtz and Gibbs energies and activated transition state reaction rates can be estimated, using easily accessible molecular properties, such as atomic weights, bond lengths, moments of inertia and vibrational frequencies. Understanding how Clausius’ virial theorem balances the internal kinetic energy with field potential energy justifies partitioning between thermal and statistical properties of entropy, yielding a more complete view of the evolutionary nature of the second law of thermodynamics. The ease of performing these operations is illustrated by three important chemical gas phase reactions, the reversible dissociation of the hydrogen molecules, lysis of water to hydrogen and oxygen and the reversible formation of ammonia from nitrogen and hydrogen. Employing the ergal also introduced by Clausius to define the reversible internal work to overcome molecular interactions plus the configurational internal work of negative Gibbs energy as a function of volume or pressure may provide a practical guide for managing risk in industrial processes and climate change at the global scale.
ARTICLE | doi:10.20944/preprints202108.0061.v1
Subject: Earth Sciences, Atmospheric Science Keywords: Keywords: local community; livelihoods; sustainability; land-water-energy-food; nexus; indicator
Online: 2 August 2021 (22:05:33 CEST)
The sustainable management of Land - Water - Energy - Food (LWEF) nexus requires an envi-ronmental characterization that allows the comparison of complex interlinkages between nexus resources and livelihoods. This complexity makes this characterization difficult coupled with limited study in quantifying sustainability of LWEF nexus and its linkage with livelihood. Therefore, the present study aimed to investigate the link between sustainable LWEF nexus and livelihoods. We used analytical hierarchy process and pairwise comparison matrix in combina-tion with weighting model. The result of composite LWEF nexus index was 0.083 representing, low sustainability. This could be linked with nexus resources consumption, use, and manage-ment. From the analysis of the weight of land, water, energy and food nexus resources, the highest weight was observed for food. The focus of on food production only shows no clear synergy on provisioning, supporting or regulating nexus resources to address livelihoods. The result further showed that LWEF nexus resources have strong correlation with livelihoods. This was evidenced by social (r>0.8, P<0.01), natural (r>0.3, P<0.05) and physical (r>0.6, P<0.01) liveli-hood indicators showed strong positive correlation with LWEF nexus resources. From this re-sults, it was observed that managing nexus resources not only provide a significant contribution to achieve sustainable LWEF nexus, but also be effective for enhancing livelihood through food security. This could be attained by strong evidence based policy to ensure sustainable use of nexus resources. The results provided by this study would serve as the foundation for future study, policy formulation and implementation.
ARTICLE | doi:10.20944/preprints202010.0045.v1
Subject: Engineering, Automotive Engineering Keywords: wells turbine; oscillating water column; wave energy converter; computational fluid dynamics
Online: 2 October 2020 (14:03:41 CEST)
The current need to develop sustainable power sources has led to the development of ocean-based conversion systems. Wells turbine is a widely used converter in such systems which suffers from a lack of operational range and power production capacity under operational conditions. The profile named IFS which is concave in the post-mid-chord region, can produce significantly larger lift forces and show better separation behavior than the NACA profiles. In the present study, we tested this profile for the first time in a Wells turbine. The performance of six different blade designs with IFS and NACA profiles were evaluated and compared using a validated computational fluid dynamic model. Although the substitution of the NACA profile with the IFS profile in all cases increased the torque generated, the most efficient power generation and the largest efficient range were achieved in the design with varying thickness from the hub with a 0.15 thickness ratio reaching to the ratio of 0.2 at the tip. The operational span of this design with the IFS profile was 24.1% greater and the maximum torque generation was 71% higher than the case with the NACA profile. Therefore, the use of the IFS profile is suggested for further study and practical trials.
ARTICLE | doi:10.20944/preprints201702.0011.v1
Subject: Engineering, Energy & Fuel Technology Keywords: absorption chiller; thermal energy transportation; solution transportation; ammonia-water; COP; simulation
Online: 4 February 2017 (07:49:12 CET)
Utilization of wasted heat instead of fuel combustion is effective to reduce primary energy consumption for mitigating global warming problem. Because wasted heat sources are not necessarily located close to areas of heat demand, one of the difficulties is that wasted heat has to be transferred from heat source side to heat demand side, which may require heat transportation over long distance. From this point we proposed and have examined new idea of heat transportation using ammonia-water as the working fluid which system is named Solution Transportation Absorption chiller, in short STA. Our previous studies of STA were mainly the experimental investigation with STA facility which cooling power was 25RT (90kW). As a result, the COP of STA was found almost same value 0.65 with the conventional absorption chiller without depending on the transportation distances. The simulation using AspenHYSYS also examined with same experimental condition. The experimental data showed good agreement with the simulation calculation. In this study, we examined the large-scale cooling power STA on simulation. The examination cooling powers were from 90 kW(25RT) to 3517 kW(1000RT). All cooling power achieved around COP 0.64 including pump power consumptions. In addition, we performed the dynamic simulation. As the results, there was no effect of pipeline size on the cooling capacities and mass flow rates. Furthermore, the stability time of the cooling capacities and mass flow rates were almost same regardless of the pipeline size and cooling capacity. In other words, STA may be achieved the same COP even though having various complex conditions compared with the conventional absorption chiller.
ARTICLE | doi:10.20944/preprints202110.0399.v1
Subject: Engineering, Energy & Fuel Technology Keywords: Renewable energy; Life cycle analysis; Wind energy; Life cycle assessment; Wind turbine; Carbon footprint; Water consumption; Greenhouse gases; non-conventional renewable sources; Carbon and water footprints.
Online: 27 October 2021 (11:00:58 CEST)
Wind technology is considered to be among the most promising types of renewable energy sources, and due to high oil prices and growing concerns about climate change and energy security, it has been the subject of extensive considerations in recent years, including questions related to the relative sustainability of electricity production when the manufacturing, assembly, transportation and dismantling processes of these facilities are taken into account. The present article evaluates the environmental impacts, carbon emissions and water consumption, derived from the production of electric energy of the Villonaco wind farm, located in Loja-Ecuador, during its entire life cycle, using the Life Cycle Analysis method. Finally, it is concluded that wind energy has greater environmental advantages, since it has lower values of carbon and water footprints than other energy sources. Additionally, with the techniques Cumulative Energy Demand and Energy Return on Investment, sustainability in the production of electricity from wind power in Ecuador is demonstrated; and, that due to issues of vulnerability to climate change, the diversification of its energy mix is essential considering the inclusion of non-conventional renewable sources such as solar or wind, this being the only way to reduce both the carbon footprint and the water supply power.
ARTICLE | doi:10.20944/preprints201911.0058.v1
Subject: Social Sciences, Organizational Economics & Management Keywords: water rights; robustness; water governance; water scarcity; water allocation; water accounting; water trading; water sharing
Online: 6 November 2019 (10:43:15 CET)
A framework for the review of existing water management systems and their transformation into robust water sharing systems is offered. The framework focuses on the need to develop efficient and equitable ways to manage water scarcity and plan to deal with the tensions scarcity imposes on any community. The framework identifies a way to bring together traditional community-managed systems with those typically used to allocate water to large water users and more commonly found in developed countries. So that use can be kept within sustainable limits while optimizing use, the framework includes mechanisms that enable the reallocation of water as demand and supply conditions change. Non-consumptive uses are recognized and environmental objectives can be delivered efficiently. Compliance with well-established accounting and hydro-logical concepts. Ways to increase the value of existing entitlements, encourage innovation and protect investments are included as options. It is recognized that the governance and legal arrangements necessary to underpin successful implantation are context specific.
ARTICLE | doi:10.20944/preprints202104.0486.v1
Subject: Earth Sciences, Atmospheric Science Keywords: Land-surface modelling system; hydrology; carbon; surface energy balance; open water; snow
Online: 19 April 2021 (13:23:53 CEST)
The land-surface developments of the European Centre for Medium-range Weather Forecasts (ECMWF) are based on the Carbon-Hydrology Tiled Scheme for Surface Exchanges over Land (CHTESSEL) and form an integral part of the Integrated Forecasting System (IFS), supporting a wide range of global weather, climate and environmental applications. In order to structure, coordinate and focus future developments and benefit from international collaboration in new areas, a flexible system named ECLand which would facilitates modular extensions to support numerical weather prediction (NWP) and society-relevant operational services, e.g. Copernicus, is presented . This paper introduces recent examples of novel ECLand developments on (i) vegetation, (ii) snow, (iii) soil, (iv) open water/lake (v) river/inundation, and (vi) urban areas. The developments are evaluated separately with long-range, atmosphere-forced surface offline simulations, and coupled land-atmosphere-ocean experiments. This illustrates the benchmark criteria for assessing both, process fidelity with regards to land surface fluxes and reservoirs of the water-energy-carbon exchange on the one hand, and on the other hand the requirements of ECMWF’s NWP, climate and atmospheric composition monitoring services using an Earth system assimilation prediction framework.
ARTICLE | doi:10.20944/preprints202003.0028.v2
Subject: Engineering, Energy & Fuel Technology Keywords: photovoltaic; solar spectrum; tandem cell; energy yield model; on-Si tandem; terminal
Online: 30 March 2020 (08:23:32 CEST)
The outdoor field test of the 4-terminal on Si tandem photovoltaic module (specifically, InGaP/GaAs on Si) was investigated and performance model, considering spectrum change affected by fluctuation of atmospheric parameters, was developed and validated. The 4-terminal on Si tandem photovoltaic module had about 40 % advantage in seasonal performance loss compared with standard InGaP/GaAs/InGaAs 2-terminal tandem photovoltaic module. This advantage is expanded in (subarctic zone) < (temperate zone) < (subtropical zone). The developed and validated model used all-climate spectrum model and considered fluctuation of atmospheric parameters, and can be applied every type of on-Si tandem solar cells.
ARTICLE | doi:10.20944/preprints201712.0132.v1
Subject: Social Sciences, Political Science Keywords: water management; water paradigm; water governability; water conflicts; Cochabamba
Online: 19 December 2017 (07:22:15 CET)
Through the process of paradigm change (water as a resource towards water as a common), the authors examine, from a theoretic point of view, the water governability proposed by Agenda del Agua Cochabamba (AdA) – Cochabamba Water Agenda – in the Cochabamba Valley (Bolivia), identifying barriers and drivers to the process that could take place. The rise of Evo Morales in Government in 2006 suggested that policy making would somehow take a fundamental turn resulting in more poor environmental-oriented water policies. However, if that was indeed the case, the implementation of these policies remain controversial as strong power asymmetries still exist at a local level that interfere with national policies shaping the political area. The Cochabamba Water Agenda echoes this debate on the political arena and contributes a politically contested water management through a paradigm change envisaging the difficulties through its implementation. The question remains if this “political” solution to paradigm change in water management may reduce water conflicts.
CONCEPT PAPER | doi:10.20944/preprints202107.0709.v1
Subject: Engineering, Automotive Engineering Keywords: Water shortages; Irrigation Water; water Use; Water Harvesting; Aquifers storage
Online: 30 July 2021 (23:38:55 CEST)
Water scarcity is a significant challenge facing Jordan today. It is a challenge in all areas that use water, and it has become certain that water is the critical factor in the population/resources equation. The water resources in Jordan have become limited with the noticeable increase in the population, mostly resulting from forced migrations in neighboring countries because of the wars and until our time. The rising natural population growth rate, along with the massive influx of refugees, has turned into a state of disproportion between the daily consumption of the population and the amount of water available. That Jordan shares most of its surface water resources with neighboring countries has exacerbated the situation. The current use of water already exceeds its renewable supply. Excessive withdrawal from aquifers, which leads to a lowering of the water table and deterioration in water quality, covered the deficit. This paper focuses on assessing the water situation in Jordan, mainly evaluating this problem and the solution being considered, the true basis for a sustainable water solution requires awareness by the population, and several governmental and non-governmental organizations are actively involved in educating residents about water shortages. The most important and 'actionable' elements of comprehensive water solutions are discussed in this paper, and these elements exist, develop extra water supplies, water harvesting, water desalination, proper wastewater reuse in the agricultural sector, and reduce the demand for drinking water. This research provides specific recommendations to address the shortage of water resources in the Kingdom and highlights the importance of water conservation and optimal use.
ARTICLE | doi:10.20944/preprints201909.0039.v1
Subject: Engineering, General Engineering Keywords: water management; planning; water resources; water sustainability policies; water laws
Online: 4 September 2019 (03:37:23 CEST)
The growing need for water has pressured society and governments to focus more on preservation, planning and management of this natural resource, in which is fundamental to ecosystems and especially to humans. In this sense, the goal of this study was to analyze the national policy of water resources in Brazil and Italy, figuring out aspects that could promote its improvement, aiming at the preservation of water sources, guaranteeing satisfactory quantity and quality. They were carried out in 2019 by the environmental agencies of both countries, listing the main disciplinary regulations. The results show that although they are countries with different realities, they resemble similarities in managerial aspects of water resources, with legislation addressing qualitative and quantitative aspects of water, with guiding principles, instruments and actions aimed at the defence of this natural resource.
ARTICLE | doi:10.20944/preprints202002.0387.v1
Subject: Engineering, Energy & Fuel Technology Keywords: hydrothermal energy; river-water heat pump; water temperature recovery distance; heat transfer equation; Environmental Fluid Dynamic Code (EFDC); Han river basin
Online: 26 February 2020 (02:58:42 CET)
Temperature differences between the atmosphere and river water allow rivers to be used as a hydrothermal energy source. The river-water heat pump system is a relatively non-invasive renewable energy source; however, effluent discharged from the heat pump can cause downstream temperature changes which may impact sensitive fluvial ecosystems. In this study, the water temperature recovery distance of the effluent was estimated for a river section in the Han River Basin, Korea, using the heat transfer equation and the Environmental Fluid Dynamic Code (EFDC) model. Results showed that, compared to the EFDC model, the heat transfer equation tended to overestimate the water temperature recovery distance due to its simplified assumptions. The water temperature recovery distance could also be used as an objective indicator to decide the reuse of downstream river water. Furthermore, as the river system was found to support an endangered fish species that is sensitive to water environment changes, care should be taken to exclude the habitats of protected species affected by water temperatures within water temperature recovery distance.
ARTICLE | doi:10.20944/preprints202102.0129.v1
Subject: Engineering, Civil Engineering Keywords: Water Sensitive City; Water Sensitive Urban Design; Water Cycle; Water Utilities
Online: 4 February 2021 (09:34:58 CET)
Mexico is currently facing important water management challenges. Cities in the country are facing water scarcity and at the same time, they struggle with floods during the raining season. The water sensitive urban design (WSUD) approach has proved to be helpful in tackling urban water challenges such as floods and water scarcity and it is being implemented in cities around the world. The WSUD approach highlights the role of both the water cycle and the water utilities systems, when transitioning towards a water sensitive stage. Therefore, the objective of this research is to analyse the current situation of the water cycle and the water utility (SIAPA). To do so, we have selected the Metropolitan Area of Guadalajara (MAG) and proposes a case study approach. Within our case of study, we answer two questions: 1) What are the causes of water scarcity and flooding in the MAG? and 2) What are the proposals to solve these problems under a WSUD approach? By answering these questions, we identified that the water management in the MAG corresponds to a single purpose infrastructure. This type of management does not contribute to solve the problems of water scarcity and floods. The water supply policy is based only on the construction of large dams disregarding the storage and use of rainwater, and reuse of greywater, and water-conservation devices. In order to transition towards a water sensitive stage, a WSUD approach that includes multi-purpose infrastructure should be considered. Such as green roofs, swales, rainwater gardens, infiltration trenches, etc.
ARTICLE | doi:10.20944/preprints201809.0269.v1
Subject: Life Sciences, Microbiology Keywords: L.pneumophila, well water, tap water, ice cubes, hospital water, hotel water
Online: 14 September 2018 (14:24:40 CEST)
Background Legionella pneumophila is one of the causes of legionellosis. Water environments serve as the natural habitat and the main sources of Legionella pneumophila. Objectives The aims of this study was to understand the differences of Legionella pneumophila serogroups distribution in well water, tap water, ice cubes, hospital and hotel water in East Java-Indonesia. Methods a total of 60 water samples in east java-Indonesia; from well water (n=25), tap water (n=5), ice cubes (n=5), water from the hospital (n=16), and hotel water (n=9) were detected using polymerase chain reaction with mip gene spesific primers and then it was analyzed by phylogenetic tree. Results For the 60 water samples collected in East Java, 12% of the samples (7/60) were positively contaminated by L. pneumophila. In details, there was 8% of the well water samples (2/25), 2% of the tap water samples (1/5), 2% of the ice cubes samples (1/5), 0% of the hospital water samples (0/16) and 33.33% of the hotel water samples (3/9). The phylogenetic tree showed that Legionella pneumophila contaminating well water isolate 1 from Surabaya and tap water isolate from Sidoarjo was closer to L.pneumophila serogroup 2, 4, 6, 8, 10, 12, isolates from Brazil, China, Spain and Australia. L.pneumophila contaminating the ice cubes from Sidoarjo was closer to serogroup 1, 2, 4, 7, 8, 11, 13, 14, while the bacteria contaminating well water isolate 2 from Sidoarjo as well as water in hotel of Surabaya (hotel water isolate 1, 2 and 3) classified into their own group. Conclusion There is a difference in the distribution of L. pneumophila serogroups between well water, tap water, ice cubes, and hotels.
ARTICLE | doi:10.20944/preprints201805.0056.v1
Subject: Earth Sciences, Environmental Sciences Keywords: water-reuse; governance capacity; water management; water scarcity
Online: 3 May 2018 (08:36:07 CEST)
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.
ARTICLE | doi:10.20944/preprints202201.0306.v1
Subject: Engineering, Construction Keywords: road,; energy-saving constructions; temperature regime; deformation of the roadbed; water migration; compaction coefficient
Online: 20 January 2022 (13:36:57 CET)
Currently, the design and construction of embankments of roads, railroads and hydraulic structures are based on regulatory documents developed 25-30 years ago. For the construction of granite massifs it is necessary to use sandy soils, the distribution of which in the Arctic zone of Siberia in the areas of construction is not more than 1.5%. In this case, the range of transport of sand in the alluvial area is 35 kilometers, in the rest of the area - an average of 60 kilometers. Large volumes of soil massifs require large amounts of transportation units, fuel consumption and are accompanied by large emissions of hydrocarbons into the atmosphere. Over the past 15 years, the authors have developed designs and technologies that significantly reduce the energy consumption during the construction of soil embankments. Combined structures are cages made of geosynthetic materials filled with unsuitable melted and frozen overmoistened clay and peaty soils. This allowed the use of soils within the construction sites and thereby reduce the range of transportation from 0.2 to 2.0 kilometers. As an example, when reducing the range of transportation from 25 km to 1 km, the energy consumption is reduced by a factor of 21. The use of geosynthetics made it possible to set the initial parameters of the water-heat regime control process, which increased the life cycle of the embankment from 2 to 5 times in comparison with traditional soil massifs and reduced the consumption of energy for repair and maintenance of linear transport structures. This article gives a theoretical substantiation of water-heat regime management, based on which new designs and technologies have been proposed and tested in Siberia in 2008-2013. The results of the tests confirm the theoretical research. Thus, the use of combined constructions of geosynthetics and inapplicable soils not only reduces the distance of transportation, but also reduces the volume of earthworks. It reduces the consumption of energy by 1.5-2 times.
ARTICLE | doi:10.20944/preprints201907.0207.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: crop intensification; energy balance; North East Hill Region; organic farming; soil health; water productivity
Online: 18 July 2019 (09:06:21 CEST)
Organic farming has positive, impact on environment, soil health, and healthy food quality. Worldwide demand for organic foods is increasing by leaps and bounds in recent years. The present investigation was undertaken during 2014 to 2018 to evaluate the effect of cowpea (Vigna unguiculata) co-culture with maize (Zea mays L.) on productivity enhancement over prevailing maize-fallow system, and to assess the feasibility of inclusion of short duration winter crops after maize with appropriate residue management practices on productivity and soil health. The experiment comprised of six cropping systems in main plot and three soil moisture conservation (SMC) measures options in sub plot. Results indicated that the inclusion of second crop in place of fallow and cowpea co-culture with maize increased average maize grain yield by 6.2 to 23.5% as compared to that of maize-fallow (MF). Use of maize stover mulch (MSM) + weed biomass mulch (WBM) increases maize grain yield by 19.1 and 6.5% over those of MSM and no mulch (NM), respectively. Various soil moisture conservation (SMC) measures had significant (p=0.05) effect on crop yields and water productivity. Double cropping system had significantly (p=0.05) higher amount of soil available NPK, soil organic carbon (SOC), microbial biomass carbon (MBC) and dehydrogenase activity (DHA) at 0-15 cm and at 15-30 cm depth than those under MF. The SWC measures of MSM+WBM had significantly higher available N, SOC, and MBC by 5.5, 4.8 and 8.1% than those under NM, respectively. Correspondingly, soils under MSM and MSM+WBM had 2.24 and 2.99% lower bulk density (ρb) in 0-15 cm and 2.21 and 2.94% lower ρb in 15-30 cm than that of NM. The energy use efficiency (EUE) was significantly higher under MCV (7.90%) over rest of the cropping sequences. MSM+WBM and MSM recorded 25.1 and 16.6% higher net energy over NM, respectively. The net return (INR 159.99×103/ha) and B:C ratio (2.86) were significantly higher with MCV system followed by MCR cropping sequence. MSM+WBM had significantly higher net return (INR 109.44×103/h), B:C ratio (2.46) over those under MSM (INR 97.6×103/h) and NM (INR 78.61×103/h). Overall the cowpea co-culture with maize and inclusion of short cycle winter crops along with MSM+WBM in maize-based cropping systems was found productive in terms of crop and water, profitable, energy efficient and sustained the soil health.
ARTICLE | doi:10.20944/preprints201608.0018.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: soil tillage; tractors; soil water content; physical soil properties; GPS; energy requirement; CO2 emission
Online: 2 August 2016 (12:50:33 CEST)
In this study the effects of three different main preparatory tillage operations [ploughing at 0.4 m (P40) and 0.20 m (P20) depth and minimum tillage at 0.20 m depth (MT) each of them carried out at two different soil water contents (WC) [low, 58% (LH) and high, 80% (HH) of field capacity] were investigated. The results obtained in this research show high values of soil strength in term of Penetration resistance (CI) and shear strength (SS) particularly in deeper soil layers at lower water content. Fossil-fuel energy requirements both for P40 LH and P20 LH were 25 and 35% higher with respect to the HH treatments and tractor slip were very high (P40 LH = 32.4%) with respect to the P40 HH treatment (16%). Therefore soil water content had significantly influenced tractor performance during soil ploughing, particularly at 0.40 m depth while MT was not influenced at all. A significant correlation between grain yield and soil penetration resistance was found highlighting how soil strength may be good indicator of its productivity. Obtained results during these field tests allowed considering MT and P20 treatments more suitable for this type of soil in climate change scenarios.
Subject: Life Sciences, Other Keywords: conservation tillage; water potential; water potential gradient; water transfer resistance; water use efficiency
Online: 9 August 2019 (04:11:21 CEST)
Water availability is a major constraint for spring wheat production on the western Loess Plateau of China. The impact of tillage practices on water potential, water potential gradient, water transfer resistance, yield, and water use efficiency (WUEg) of spring wheat was monitored on the western Loess Plateau in 2016 and 2017. Six tillage practices were assessed, including conventional tillage with no straw (T), no-till with straw cover (NTS), no-till with no straw (NT), conventional tillage with straw incorporated (TS), conventional tillage with plastic mulch (TP), and no-till with plastic mulch (NTP). No-till with straw cover, TP, and NTP significantly improved soil water potential and root water potential at the seedling stage and leaf water potential at the seedling, tillering, jointing, and flowering stages, compared to T. These treatments also significantly reduced the soil-leaf water potential gradient at the 0-10 cm soil layer at the seedling stage and at the 30-50 cm soil layer at flowering, compared to T. Thus, NTS, TP, and NTP reduced soil-leaf water transfer resistance and enhanced transpiration. Compared to T, the NTS, TP, and NTP treatments significantly increased biomass yield (BY) by 18, 36, and 40%, respectively, and grain yield (GY) by 28, 22, and 24%, respectively, with corresponding increases in WUEg of 24, 26, and 24%, respectively. These results demonstrate that NTS, TP, and NTP improved GY and WUEg of spring wheat by decreasing the soil-leaf water potential gradient and soil-leaf water transfer resistance and enhancing transpiration, and are suitable tillage practices for sustainable intensification of wheat production in semi-arid areas.
ARTICLE | doi:10.20944/preprints202207.0076.v1
Subject: Medicine & Pharmacology, General Medical Research Keywords: water consumption; drinking water; consumer preference; water usage purposes
Online: 5 July 2022 (13:45:20 CEST)
The aim were to determine the drinking water preferences of people applied to a family health center. This cross-sectional study was carried out from April 01st to May 31st, 2022. The data were evaluated using the chi-square test and percent ratios with a significant of P < 0.05. The mean age of all 432 respondents was 48.03±15.86. It was determined that those aged 31-45 had drunk more bottled water (p<0.01) and more spring water (p<0.001), that those aged 65 and over more purified water (p<0.001), that women more tap water (p<0.001), that married people had drunk more demijohn and tap water (p<0.001, each one), that divorced/widows had drunk more packaged and purified water (p<0.001, each one), that the illiterate/literate bottled water (p<0.001, per one), that those who had no income/people who lived on the state or municipal assistance only carboy water (p<0.001). This study suggests that the biggest factor that positively affected the drinking water preference was the packaging of the water. However, the drinking rates of mains water and spring water were quite low. Convincing the authorities to make the mains water drinkable is of great importance in terms of overcoming the public's distrust of mains water.
ARTICLE | doi:10.20944/preprints202201.0334.v1
Subject: Engineering, Other Keywords: Sustainability model; SDGs; Clean water; Drinking water; Water security.
Online: 24 January 2022 (02:08:49 CET)
Water resources are under pressure because of human activities. Its management faces the challenge of enhancing long-term water security while minimizing undesirable economic, social, and environmental impacts along with its production chain. Since water and wastewater treatment plants are designed to maintain and conserve freshwater provisioning services, it is paramount to understand how it operates before proposing options for sustainability. At this point, the diagnosis phase claims for methods scientifically-based, systemic, and more objective to provide information for decision-makers towards strategic management of water resources. This work applies the five-sector sustainability model (5SenSu) to assess Brazil's twenty major water and wastewater treatment companies (WWTC) to quantify their sustainability levels that allow ranking procedures and the establishment of benchmarks for improvements. Under comparative basis, results identified the top-three sustainable companies, CORSAN, CASAN, and SANEPAR, which should be considered examples of best practices. Specifically, the following best-ranked companies in each sector within 5SenSu should be used as benchmark patterns for more oriented best practices: SANEAGO, sector 1; AGESISA, sector 2; CORSAN, sector 3; CASAL, sector 4; MA, sector 5. This work contributes to the advancement in modeling sustainability assessment of human-managed systems (applied in WWTCs in this present study) from a systemic and epistemologically rooted approach, avoiding shortcomings and misleading discussions on the sustainability issue. Quantifying sustainability of WWTCS from 5SenSu allows the identification of those sectors/indicators that requires immediate cleaner production practices by decision-makers to improve overall sustainability, besides identifying those companies more aligned with the requirements of UN SDGs.
ARTICLE | doi:10.20944/preprints202109.0509.v1
Subject: Earth Sciences, Environmental Sciences Keywords: Hygiene; Cleanliness; Water; Rural water facility; Water shortage; Uganda
Online: 30 September 2021 (11:02:14 CEST)
This research contributes to the detailed discussion about the approach to secure, hygienic water and cleanliness in Uganda and its pastoral regions. The relationship between the sanitation and clean water access with destitution is also discussed. Although this document is not leading towards the policy recommendation but it is an overall idea of how Uganda progressed because of the provisions adopted by the government, local and international organizations, and NGOs, and how the country lacked before these steps taken. Most of the data mentioned is taken from the house surveys of a decade 2002-2013 alongside the qualitative data. Literature review is also considered and is divided in two sections: first included researches related to water accessibility and usage, while the second section included researches related to work done and progress for diarrheal diseases and sanitation. Afterwards, methodologies were discussed where, firstly, trends and then the limitations in access to the basic necessities of life that is clean water and hygiene are mentioned. At last, the implementations and how they affected the rural Ugandans was discussed.
ARTICLE | doi:10.20944/preprints202002.0149.v1
Subject: Engineering, Civil Engineering Keywords: Water Demand; Water Supply; Performance; Hydraulic Modeling; Water GEMSV8i
Online: 11 February 2020 (14:52:17 CET)
This study was conducted generally by aiming assessment of the hydraulic performance of water distribution systems of Addis Ababa Science and Technology University (AASTU). In line with the main objective, this study addressed, (1) pinpointing problems of existing water supply versus demand deficit (2) evaluating the hydraulic performance of water distribution system using water GEMS and (3) recommended alternative methods for improving water demand scenarios. The University’s water supply distribution network layout was a looped system and the flow of water derived by both gravity and pressurized system. The gravity flow served for the academic and administrative staffs whereas the pressurized system of the network fed the students dormitories, cafeteria’s etc. The study revealed the existence of unmet minimum pressure requirement around the student dormitories which accounts 25.64% below the country’s building code standard during the peak hour consumption. The result of the water demand projection showed an increment of 2.5 liter per capita demand (LPCD) in every five years. Hence, first, the university’s water demand was projected and then hydraulic parameters such as; pressure, head loss and velocity were modeled for both the existing and the improved water supply distribution. The finding of the study was recommended to the university’s water supply project and institutional development offices for its future modification and rehabilitation works.
ARTICLE | doi:10.20944/preprints202108.0497.v1
Subject: Biology, Plant Sciences Keywords: leaf water content; hyperspectral spectroscopy; leaf water potential; drought; diurnal cycle; plant water status; relative water content; equivalent water thickness; Dracaena marginate; water stress; leaf water variation
Online: 25 August 2021 (15:00:37 CEST)
Water plays a crucial role in maintaining plant functionality and drives many ecophysiological processes. The distribution of water resources is in a continuous change due to global warming affecting the productivity of ecosystems around the globe, but there is a lack of non-destructive methods capable of continuous monitoring of plant and leaf water content that would help us in understanding the consequences of the redistribution of water. We studied the utilization of novel small hyperspectral sensors in the 1350-2450 nm spectral range in non-destructive estimation of leaf water content in laboratory and field conditions. We found that the sensors captured up to 96% of the variation in equivalent water thickness (EWT, g/m2) and up to 90% of the variation in relative water content (RWC). These laboratory findings were supported by field measurements, where repeated leaf spectra measurements were in good agreement (R2=0.79) with a time-lagged change of tree xylem diameter. Further tests were done with an indoor plant (Dracaena marginate Lem.) by continuously measuring leaf spectra while drought conditions developed, which revealed detailed diurnal dynamics of leaf water content. We conclude that close-range hyperspectral spectroscopy can provide a novel tool for continuous measurement of leaf water content at the single leaf level and help us to better understand plant responses to varying environmental conditions.
ARTICLE | doi:10.20944/preprints201712.0030.v1
Subject: Engineering, Mechanical Engineering Keywords: cylindrical parabolic reflector; nail twist pitch ratio; water storage tank; thermal efficiency; solar energy collected
Online: 5 December 2017 (13:28:36 CET)
This paper reports the overall thermal performance of a cylindrical parabolic concentrating solar water heater (CPCSWH) with inserting nail type twisted tape (NTT) in the copper absorber tube for the nail twist pitch ratios 4.787, 6.914 and 9.042 respectively. The experiments are conducted for a constant volumetric water flow rate and during the time period 9:00 h to 15:00 h. The useful heat gain, hourly solar energy collected and hourly solar energy stored of this solar water heater are found higher for nail twist pitch ratio 4.787. The above said parameters are found to be a peak at noon and observed to follow the path of variation of solar intensity. At the starting of the experiment, the value of charging efficiency is observed to be maximum. Whereas the maximum value of instantaneous efficiency and overall thermal efficiency are observed at noon. The key finding is that the nail twist pitch ratio enhances the overall thermal performance of the CPCSWH.
REVIEW | doi:10.20944/preprints201710.0081.v1
Subject: Life Sciences, Other Keywords: dietary assessment; food record; FFQ; biomarker; doubly labeled water; energy intake; validity; athletes; sports nutrition
Online: 12 October 2017 (09:43:35 CEST)
Dietary assessment methods recognized as appropriate for the general population are usually applied in a similar manner to athletes, despite knowledge that sport-specific factors can complicate assessment and impact accuracy in unique ways. As dietary assessment methods are used extensively within the field of sports nutrition, there is concern the validity of methodologies have not undergone more rigorous evaluation in this unique population sub-group. The purpose was to systematically review studies comparing two or more methods of dietary assessment, including dietary intake measured against biomarkers or reference measures of energy expenditure, in athletes. Six electronic databases were searched for English-language, full-text articles published from January 1980 until June 2016. The search strategy combined the following keywords: diet, nutrition assessment, athlete and validity; where the following outcomes are reported but not limited to: energy intake, macro and/or micronutrient intake, food intake, nutritional adequacy, diet quality, or nutritional status. Meta-analysis was performed on studies with sufficient methodological similarity, with between-group standardized mean differences (or effect size) and 95 % confidence intervals (CI) calculated. Of the 1624 studies identified, 18 were eligible for inclusion. Studies comparing self-reported energy intake (EI) to energy expenditure assessed via doubly labelled water were grouped for comparison (n=11) and demonstrated mean EI was under-estimated by 19 % (- 2793 ± 1134 kJ/d). Meta-analysis revealed a large pooled effect size of - 1.006 (95% CI: -1.3 to -0.7; p<0.001). The remaining studies (n=7) compared a new dietary tool or instrument to a reference method(s) (e.g. food record, 24-h dietary recall, biomarker) as part of a validation study. This systematic review revealed there are limited robust studies evaluating dietary assessment methods in athletes. Existing literature demonstrates substantial variability between methods, with under and misreporting of intake frequently observed. There is a clear need for careful validation of dietary assessment methods, including emerging technical innovations, among athlete populations.
ARTICLE | doi:10.20944/preprints201804.0357.v1
Subject: Engineering, General Engineering Keywords: hydrokinetic; energy assessment; unregulated river; daily water velocity estimation; daily water level estimation; IBM statistical package for social sciences (SPSS); regression analysis; east malaysia
Online: 27 April 2018 (08:39:22 CEST)
Electrification coverage in Sarawak is the lowest at 78.74%, compared to Peninsular Malaysia at 99.62% and Sabah at 82.51%. Kapit, Sarawak with its 88.4% populations located in rural areas and mostly situated along the main riverbanks has great potential to generate electrical energy by hydrokinetic system. Yearly water velocity data is the most significant parameter to perform hydrokinetic analysis study. Nevertheless, the data retrieved from local river databases are inadequate for river energy analysis, thus hindering its progression. Instead, flow rates and rainfall data had been utilised to estimate the water velocity data. This signifies no estimation of water velocity in an unregulated river by using water level data had been made. Therefore, a novel technique of estimating the daily average water velocity data in unregulated rivers is proposed. The modelling of regression equation for water velocity estimation was performed and two regression model equations were generated to estimate both water level and water velocity on-site and proven to be valid as the coefficient of determination values had been R2 = 87.4% and R2=87.9%, respectively. The combination of both regression model equations can be used to estimate long-term time series water velocity data for type-C unregulated river in remote areas.
CASE REPORT | doi:10.20944/preprints202008.0049.v1
Subject: Keywords: diarrhoeal cases; drinking water; water sources; water pollution; Darbandikhan Lake
Online: 2 August 2020 (17:41:51 CEST)
Water pollution in Iraq has been extended disaster edge; this pollution is caused by wastes and sewages into soil and rivers, pollutant water sources influence the outbreak and serious epidemic status among the population.. The aim of this study is to determine the bacteriological quality of drinking water sources and characteristics of water-borne diseases especially diarrheal cases in Darbandikhan city. 166 water samples, collected from the different sources and areas, were tested for the presences of coliform bacteria as an indicator for pathogen contamination. Most probable number index was used for coliform enumeration. 161 diarrheal cases were taken as a sample from the patients were admitted to the general hospital in Darbandikhan district.. The questionnaire form was planned to view characteristics of diarrheal cases and patients were interviewed directly, the data was analyzed by STATA software application. 46% of the diarrheal cases used tap water for drinking. On the other hand, the reminder (54%) used other sources for the same purpose. All the risk factor such as type of water source, sufficiency of the water, duration of water storage and chlorination were associated with diarrhea. Almost half of the cases were children and three quarters were single. The data was analyzed by STATA version 13.1.This study indicated that the majority of drinking water sources in Darbandikhan city are not suitable for drinking, although net pipe system supplied chlorine significantly it has been proven that the tap water from the homes is not suitable for consumption.
ARTICLE | doi:10.20944/preprints201909.0054.v1
Subject: Engineering, Other Keywords: Shanghai; water quality; eutrophication; conventional water treatment; secondary water pollution
Online: 5 September 2019 (07:47:59 CEST)
Shanghai is experiencing water supply problems caused by heavy pollution of its raw water supply, deficiencies in its treatment processes and water quality deteoriation in the distribution system. However, little attention has been paid these problems of water quality in raw water, water treatment and household drinking water. Based on water quality data we show that the raw water sources of the Huangpu River and the Changjiang (Yangtze River) estuary are polluted by microbes (TBC), eutrophication (TP, TN and NH3-N), heavy metals (Fe, Mn and Hg) and organic contamination (chemical oxygen demand [COD], detergent and volatile phenols [VP]). The average concentrations of these contaminants in the Huangpu River are almost double that of the Changjiang estuary forcing a rapid shift to the Changjiang estuary for raw water. In spite of filtering and treatment, TN, NH3-N, Fe, COD and chlorine maxima of the treated water and drinking water still exceed the Chinese National Standard (GB5749). We determine that the relevant threats from water source to household water in Shanghai are: 1) eutrophication arising from highly concentrated TN, TP, COD and algal density in the raw water; 2) increasing salinity in the river estuary, especially at the Qingcaosha Reservoir (currently the major freshwater source for Shanghai); 3) more than 50% of organic constituents and by-products remain in treated water; 4) bacteria and turbidity increase in the course of water delivery to users. The analysis presents an holistic assessment of the water quality threats to metropolitan Shanghai in relation to the city’s rapid development.
ARTICLE | doi:10.20944/preprints201810.0427.v1
Subject: Social Sciences, Political Science Keywords: Water recycle; upscaling; water governance; water availability; climate change adaptation
Online: 18 October 2018 (16:34:29 CEST)
Cleaning wastewater and using it again for secondary purposes is a measure to address water scarcity in urban areas. However, upscaling of recycled water schemes is challenging due to the possible emergence of various barriers. Based on a review of the governance literature we suggest that a set of five governance conditions is necessary for a successful upscaling of recycled water schemes; (1) policy leadership, (2) policy coordination, (3) availability of financial resources, (4) awareness of a problem, and (5) the presence of a public forum. In order to elaborate on the practical relevance of these conditions we studied a recycled water scheme currently being upscaled in Sabadell, Spain. We reviewed policy documents, conducted a set of 21 semi-structured interviews, and attended two policy meetings about the subject. Our results suggest that Sabadell meets the required conditions for upscaling reused water to a certain extent. However, the presence of a public forum is lacking. We discuss the implications of the absence of the venue and procedures for public participation in Sabadell and how it could be strengthened. Following this discussion, we conclude with some lessons for other cities that plan to upscale their recycled water schemes.
ARTICLE | doi:10.20944/preprints201612.0059.v1
Subject: Earth Sciences, Environmental Sciences Keywords: water footprint; bottled water; groundwater; Africa; water resource management; urban
Online: 10 December 2016 (08:41:51 CET)
Packaged water consumption has grown rapidly in urban areas of many low and middle income countries, but particularly in Ghana. However, the sources of water used by this growing packaged water industry and its implications for water resource management and transport-related environmental impacts have not been described. This study aimed to assess the spatial distribution of regulated packaged water production in Ghana, both in relation to demand and for natural mineral water, to hydrogeological characteristics. 764 addresses for premises licenced to produce packaged water from 2009-2015 were mapped and compared to regional sachet water consumption and beverage import/export data examined. We find evidence to suggest packaged water is transported shorter distances in Ghana than in developed countries. For natural mineral waters, producers should be able to address the most widespread water quality hazards (including high salinity, iron and nitrates) in aquifers used for production through reverse osmosis treatment. The study suggests there is scope to integrate beverage product and groundwater regulatory databases to support groundwater management.
REVIEW | doi:10.20944/preprints202102.0344.v1
Subject: Social Sciences, Accounting Keywords: water supply; crisis situation; safety of water supply; flood; water decontamination; water filtration; flexible tanks
Online: 17 February 2021 (07:56:01 CET)
Various methods of water purification, the aim of which is to obtain such a purity class that makes it suitable for consumption are presented in the article. It is a review of solutions, ranging from methods known and used for over 100 years, through research and experiments underway, to those that are only a concept. Some of the solutions are so effective that they should also be combined with the possibility of safe storage of purified water. Flexible tanks are used for this, which significantly improve logistics and provide a supply of water in all places where it is needed.
ARTICLE | doi:10.20944/preprints202208.0510.v1
Online: 30 August 2022 (06:00:56 CEST)
The occurrence of potential spikes in a cell is a sign of life, and it is called action potential. There is a common notion that neuron signal conduction is the conduction of action potential. Hence, action potential is a typical and essential life activity. However, such potential spikes occur even in simple nonliving systems. According to the experimental observations by Pollack, structured water molecules can generate a negative potential environment. From this observation, the potential spike generation process for both living and nonliving systems caused by ion and water molecule adsorption-desorption process could be explained in this paper. So, taking into consideration the electrically neutral water molecules,the action potential generation mechanism could be explained. It is a fully inanimate model. Hence, the action potential may not be a life activity. Here, the role of water molecules in life is investigated further. It was found that the phase transition of the membrane is involved in the neuron signal conduction, but the membrane phase transition could be due to the change of state of the water molecules, which forms a large-scale structure in the cavities created by a number of lipids.
ARTICLE | doi:10.20944/preprints201906.0191.v1
Subject: Mathematics & Computer Science, Information Technology & Data Management Keywords: water data management; urban water system; strategic planning; integrated water management
Online: 20 June 2019 (04:02:14 CEST)
Rapid technological advancements in information communication technologies have enabled water resource data collection at greater spatial and temporal scale. However, this water data is often limited to the purposes of its primary collection, and limits decisions made by stakeholders towards sustainable urban water management. This empirically focused research paper examines how water practitioners involved in strategic planning can capture additional values from integrating different water data. Furthermore, the perception of 22 urban water practitioners across Australia are presented, regarding the importance of and difficulty in using water data for strategic planning, and the necessary steps for achieving integrated water management practices. Interviewees perception revealed gaps in available water resource data (i.e. water quality, ground water, stormwater, and urban water use), and limitations of industry guidelines for operating within existing governance frameworks. Overall, the research highlights the Australian urban water sector’s perception of water data’s crucial role in representing stakeholders interest; however, changes made in water data’s collection are required for an integrated water management approach. Implications for future open water data standard are discussed.
ARTICLE | doi:10.20944/preprints201809.0275.v1
Subject: Earth Sciences, Environmental Sciences Keywords: water scarcity; water withdrawal; food security; water management; climate change; adaptation
Online: 16 September 2018 (07:38:53 CEST)
Water scarcity is significantly increasing water stress in Africa and some parts of the world. This is due to human induced factors such as climate change, increase of human population that raises demand which outstrips food availability, and put great changes of land use which results in changes of hydrological mechanics and water availability as whole. The investigation was through literature review and it tries to examine the criticality of water scarcity in Africa regions, and the major factors that mastermind this menace. Also possible strategies that can be promptly used to manage water scarcity at domestic level and in agriculture are described in this paper, not with standing the fact that agriculture sectors in Africa and the rest of the world remain the utmost vulnerable enterprise to water scarcity and withdrawal on the planet earth.
ARTICLE | doi:10.20944/preprints201805.0199.v2
Subject: Earth Sciences, Environmental Sciences Keywords: Water Security, Groundwater assessment, Groundwater quality, India
Online: 31 May 2018 (16:47:27 CEST)
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.
ARTICLE | doi:10.20944/preprints202005.0344.v1
Subject: Materials Science, Surfaces, Coatings & Films Keywords: conversion efficiency; energy harvesting or generation; hot water treatment; nanorods; solar cells; surface etching; surface morphology
Online: 21 May 2020 (10:08:55 CEST)
Zinc-oxide (ZnO) nanostructures including nanorods are currently considered as a pioneer research of interest world-wide due to their excellent application potentials in various applied fields especially for the improvement of energy harvesting photovoltaic solar cells (PSC). We report on the growth and morphological properties of zinc-oxide (ZnO) nanorods grown on the surface of plain zinc (non-etched and chemically etched) plates by using a simple, economical, and environment-friendly technique. We apply hot water treatment (HWT) technique to grow the ZnO nanorods and varies the process parameters, such as temperature and the process time duration. The morphological, and elemental analysis confirm the agglomeration of multiple ZnO nanorods with its proper stoichiometry. The obtained nanostructures for different temperatures with different time duration showed the variation in uniformity, density, thickness and nanonorods size. The ZnO nanorods produced on the etched zinc surface were found thicker and uniform as compared to those grown on the non-etched zinc surface. This chemically etched Zinc plates preparation can be an easy solution to grow ZnO nanorods with high density and uniformity suitable for PSC applications such as to enhance the energy conversion efficiency of the photovoltaic (PV) solar cells towards the future sustainable green earth.
REVIEW | doi:10.20944/preprints202208.0223.v1
Subject: Earth Sciences, Other Keywords: Behavioral nudges; water conservation; technology; water efficiency
Online: 11 August 2022 (13:37:12 CEST)
Growing water shortages for large regions of the arid regions of the world, are likely to become more recurrent as climate change impacts grow. Countries across the world are facing water security difficulties that stem from population growth, urbanization, and rapid industrialization. The use of behavioral nudges methods implemented to encourage a socially desired behavior at a low to zero cost, has been an effective method at reducing water consumption in places where they have been deployed. For example, studies in California USA, Barcelona Spain, and Australia indicate that adoption of nudges give significant positive results in water consumption reduction. We describe some of the barriers that make it difficult to implement behavioral nudges to address the water crises in Sub-Saharan Africa (SSA). We investigate the literature available in Sub-Saharan Africa and discover that the application of behavioral nudges has been sparingly used for reasons that are not obvious at first glance. Second, we find that the potential impediments to the use of behavioral nudges in SSA to be awareness, inadequate access to science and technology, political systems that are poorly suited for implementing nudging, abundance of multiple ethnic groups that speak different languages, along with other barriers that could challenge implementation of behavioral nudges. In light of those barriers, we present a conceptual model with a potential to address these barriers to behavioral nudging a workable solution in SSA.
ARTICLE | doi:10.20944/preprints202207.0237.v1
Subject: Social Sciences, Economics Keywords: crop diversification; resilience; water management; water efficiency
Online: 15 July 2022 (14:54:43 CEST)
The specialisation and intensification in agriculture have increased the productivity but have also led to the spread of monocultural systems, simplifying production and reducing genetic diversity. The purpose of this study was to propose crop diversification as a tool to increase biodiversity and achieve sustainable and resilient intensive agriculture, particularly in areas with water scarcity. In this paper, a combined Life Cycle Assessment (LCA) and Life Cycle Costing (LCC) was applied to evaluate the environmental and economic sustainability of a differentiated system of cultivation (pomegranate, almond and olive), according to modern intensive and superintensive cropping systems. Based upon the results obtained, it is deduced that pomegranate cultivation generated the highest environmental load, followed by almond and olive. From the financial analysis, it emerged that almond is the most profitable, followed by pomegranate and olive.
ARTICLE | doi:10.20944/preprints202009.0230.v1
Online: 10 September 2020 (09:04:18 CEST)
This work investigates the utility of the National Oceanic and Atmospheric Administration’s National Water Model (NWM) for water management operations by assessing the total inflow into a select number of reservoirs across the Central and Western U.S. Total inflow is generally an unmeasured quantity, though critically important for anticipating both floods and shortages in supply over a short-term (hourly) to sub-seasonal (monthly) time horizon. The NWM offers such information at over 5,000 reservoirs across the U.S., however, its skill at representing inflow processes is largely unknown. The goal of this work is to understand the drivers for both well performing and poor performing NWM inflows such that managers can get a sense of the capability of NWM to capture natural hydrologic processes and in some cases, the effects of upstream management. We analyzed the inflows for a subset of Bureau of Reclamation (BoR) reservoirs within the NWM over the long-term simulations (retrospectively, seven years) and for short, medium and long-range operational forecast cycles over a one-year period. We utilize ancillary reservoir characteristics (e.g. physical and operational) to explain variation in inflow performance across the selected reservoirs. In general, we find that NWM inflows in snow-driven basins outperform those in rain-driven, and that assimilated basin area, upstream management, and calibrated basin area all influence the NWM’s ability to reproduce daily reservoir inflows. The final outcome of this work proposes a framework for how the NWM reservoir inflows can be useful for reservoir management, linking reservoir purposes with the forecast cycles and retrospective simulations.
REVIEW | doi:10.20944/preprints201810.0634.v1
Subject: Life Sciences, Microbiology Keywords: Recreational water, spa, thermal water, innovative treatment
Online: 26 October 2018 (15:09:47 CEST)
Natural spa springs are diffused all over the world and their use in pools is known since ancient times. This review underlines the cultural and social spa context focusing on hygiene issues, public health guidelines and emerging concerns regarding water management in wellness or recreational settings. The question of the "untouchability" of therapeutic natural waters and their incompatibility with traditional disinfection processes is addressed considering the demand for effective treatments that would respect the natural properties. Available strategies and innovative treatments are reviewed, highlighting potentials and limits for a sustainable management. Alternative approaches comprise nanotechnologies, photocatalysis systems, advanced filtration. State of the art and promising perspectives are reported considering the chemical-physical component and the biological natural complexity of the spa water microbiota.
ARTICLE | doi:10.20944/preprints201907.0019.v1
Subject: Earth Sciences, Environmental Sciences Keywords: community-owned water supply organization (COWSO); domestic water management strategy; water quality; water supply and sanitation authority (WSSA)
Online: 1 July 2019 (15:07:50 CEST)
Water supply is a mandatory service for Tanzanians from respective legal public water utilities, and their sustainability reflects implementations of best management strategies at a local level. The objective of this study was to assess current approaches used in water quality and quantity management in Tanzania. This was achieved through secondary water data tends, on-site water quality assessments, visits of respective water supply and sanitation authorities, and assessment of their performances. It was observed that water supplied in rural-based authorities was quite different from that supplied in an urban setting as far as quality and quantity is concerned, urban-based supplies being of assistance to users over rural ones. A new strategy on water management is presented for sustainable water supply in Tanzania; it is based on controlling groundwater abstractions and preference of surface water in public water supplies. Rural water supply management must learn several practices realized at urban supplies for the betterment of respective majority water users.
ARTICLE | doi:10.20944/preprints202208.0318.v1
Subject: Arts & Humanities, Other Keywords: Drinking water management; drinking water criteria; groundwater; reverse osmosis; sustainable development; water aesthetics
Online: 17 August 2022 (10:08:44 CEST)
A Water demand per capita will rise in the Arab world as a result of climate change and population expansion. One of the most important aims in coping with population increase around the world is to conserve water supplies. As a result, the Kingdom of Saudi Arabia constructed Al Wajeed Water Treatment System to meet the demands of the southern population. This research aims to assess the drinking water quality produced from the AlWajeed Water Treatment System. Monthly water samples were collected (January 2018 to January 2021) from the Al Wajeed Water Treatment Framework (4sites), extending to governorates; Bishah`s distribution system (5sites) and Tathleeth`s distribution system (7sites). Water quality criteria, such as physical, chemical, and microbiological parameters, revealed that the majority of water samples collected from the Al Wajeed Water Framework and its environs are of a good quality matched the national and international standards. Few sites showed water quality criteria, such turbidity, fluoride and total coliform did not comply with national and global standards. The obtained results explained the importance of monitoring and follow-up programs for drinking water criteria. In addition, they can help the authorities and stakeholders in the sustainable development.
ARTICLE | doi:10.20944/preprints202106.0436.v1
Subject: Earth Sciences, Atmospheric Science Keywords: Water Framework Directive; River Basin Management Plan; Water Resource Management; Water Governance; Stakeholders
Online: 16 June 2021 (10:29:51 CEST)
The River Basin Management Plan (RBMP) is an essential component of the European Union Water Framework Directive that details an integrated approach required to protect, improve and sustainably manage water resources. RBMP were intended to be produced for the periods 2009-2015, 2016-2021 and 2022-2027. However, after two years of delays in the development processes, the Republic of Ireland produced its first RBMP in 2010. The second RBMP cycle was also implemented in 2018 and is expected to run until the end of 2021 to give way to the third RBMP, whose consultation processes have been ongoing since December 2019. This paper contributes to the forthcoming RBMP by assessing stakeholders’ perspectives on the second RBMP through a desk-based review and by conducting interviews with nine institutions (14 interviewees). The qualitatively analysed interviews reveal a broad spectrum of actors associated with water management and governance in the Republic of Ireland through a three-tier governance structure that has been delivered (with amendment) through the first two RBMPs. Organisations such as the An Fóram Uisce|The Water Forum, the Environmental Protection Agency, the Local Authority Waters, and the Agricultural Sustainability Support and Advisory Programme have responsibilities designated in the RBMPs to deliver improved water quality, integrated catchment management, community engagement and awareness-raising. Trust has also been building up among these organisations and other agencies in the water sector. Despite these responsibilities and progress, the interviews identified communication lapses, ineffective collaboration and coordination among stakeholders and late implementation to be hampering the successful delivery of the second RBMP, in addition to significant pressures acting on water bodies from agricultural activities and urban wastewater treatment. Towards the third RBMP, the paper concludes that optimised water sector finance, enhanced and well-resourced communications, and improved stakeholder collaboration are needed to foster effective and efficient water services delivery and quality. More so, given the cross-cutting impact of the Sustainable Development Goals on water resources and the interconnected relations among the goals, the paper further recommends the integration of the SDGs in the various plans of actions and a co-benefits approach to derive the triple benefits from biodiversity, climate change initiatives and water quality measures.
Subject: Social Sciences, Other Keywords: Water Conservation; Customer Segmentation; Pro-Environmental Behaviour; Smart Water Meters; Water-use Feedback
Online: 7 May 2021 (09:41:56 CEST)
In response to droughts, various media campaigns and water saving instructions are released, often however, with only temporary water conservation effects. A promising development is this regard are Digital Water Meters (DWM) that provide near real-time water-use feedback. Despite extensive DWM experience in some water-stressed regions, a profound understanding of the initial attitude towards DWM and message tailoring opportunities are rarely empirically explored. Therefore, we aim to obtain insights into the attitude towards the introduction of DWM and explore opportunities for message tailoring, a topic of extra relevance as we may be on the threshold of a large-scale implementation in many world regions. Messages tailored to (i) normative beliefs and attitudes on drinking water, (ii) water-use activity and (iii) phase of decision-making, seem particularly compatible with DWM. Through a survey (n=1037) in the Netherlands, we observe that 93% of respondents have no objections utility investments in DWM and that 78% would accept a free DWM because of improved leakage detection, lower costs and environmental considerations. Finally, instead of sociodemographic factors, we observed that an attitude-based customer segmentation approach proved an especially useful predictor of respondent’s motivation to endorse DWM and forms a promising basis for water conservation message-tailoring strategies.
Subject: Engineering, Automotive Engineering Keywords: Azerbaijan sustainable development; water electric heating; energy efficiency; green buildings; fuzzy logic temperature control; greenhouse gas emission.
Online: 12 April 2021 (15:13:45 CEST)
This paper discusses domestic problem of waiting hot water for the shower use till it reaches satisfactory temperature, which result a lot of wastage in fresh water. The outcome from research survey shows that there is no satisfactory solution till now as all solutions were either expensive or with no effective results. Local small inline electric heater equipped with fuzzy logic controller is proposed in this paper to be installed just before the showerhead to measure the water temperature and flow before the showerhead, as control input-variables, and decide the operating voltage of the heater, as control output-variable (MISO). MATLAB Simulink is used to model the proposed system. Different test cases are simulated to prove the performance and the safe operation of the system. Techno-economic study is carried out to determine the “Direct Benefits” and “Indirect Benefits” that can be achieved if such system is implemented in wide range. Azerbaijan data is taken as an example to calculate the economic benefits. The results show important benefits not only for economy but also for climate and the reduction of CO2 gas emission. Different economic indices are provided to be an easy reference for decision makers and project managers.
ARTICLE | doi:10.20944/preprints202104.0195.v1
Subject: Medicine & Pharmacology, Allergology Keywords: doubly labeled water; total energy expenditure; physical activity level; lactate threshold, physical fitness; International Physical Activity Questionnaire
Online: 7 April 2021 (11:32:02 CEST)
Adequate energy intake is critical for the healthy longevity of older adults, and the estimated energy requirement is determined by total energy expenditure (TEE). We aimed to identify the relationship between measured aerobic capacity and TEE, activity energy expenditure (AEE) or physical activity level (PAL) with the doubly labeled water (DLW) methods in the advanced older adults. A total of 12 physically independent older adults (10 males and 2 females) aged between 81 to 94 years participated in this study. Aerobic capacity was evaluated according to the lactate threshold (LT). TEE under free-living conditions was assessed using the DLW method, and self-reported physical activity was obtained through the Japanese version of the International Physical Activity Questionnaire (IPAQ). LT was significantly positively correlated with TEE, AEE, and PAL after adjustment for age and sex (ρ= 0.77 (P<0.01), 0.86 (p<0.01), and 0.86 (p<0.01), respectively). We found the LT as an aerobic capacity is positively and independently correlated with TEE, AEE or PAL. The present results suggest that maintaining aerobic capacity is an important factor for preventing frailty, although further research is needed to multisite studies and many samples.
ARTICLE | doi:10.20944/preprints201901.0206.v1
Subject: Earth Sciences, Environmental Sciences Keywords: Strip-mined land; bioenergy; biomass; energy crop; miscanthus; SWAT model; SWAT-CUP; runoff; nutrients; and water quality
Online: 21 January 2019 (10:57:36 CET)
Strip-mined land (SML) disturbed by coal-mining is the non-crop land resource that can be utilized to cultivate high-yielding energy crops such as miscanthus for bioenergy applications. However, the biomass yield potential, annual availability and environmental impacts on growing energy crops in SML are less understood. In this study, we estimated the yield potential of miscanthus (Miscanthus sinensis) in SML and its environmental impacts on local streams using the Soil and Water Assessment Tool (SWAT). After calibration and validation of the SWAT model, the results demonstrated that miscanthus yield potentials were 2.6 (0.8−5.53), 10.0 (1.3−16.0) and 16.0 (1.34−26.0) Mg ha-1 with the fertilizer application rate of 0, 100, and 200 kg-N ha-1 respectively. Furthermore, cultivation of miscanthus in the SML has the potential to reduce sediment (~20%) and nitrate (2.5%−10.0 %) loads reaching to water streams with a marginal increase in phosphorus load. The available SML in the United States could produce about 10 to 16 dry Tg of biomass per year without negatively impacting the water quality. In conclusion, SML can provide a unique opportunity to produce biomass for bioenergy applications, while improving stream water quality in highly dense mining area (the Appalachian region) in the United States.
ARTICLE | doi:10.20944/preprints201710.0147.v1
Subject: Earth Sciences, Other Keywords: energy dissipation; hydraulic jump; Froude number; stilling basin with shallow-water cushion; large eddy simulation; hydraulic characteristics
Online: 23 October 2017 (08:30:57 CEST)
The water cushion depth of stilling basin with shallow-water cushion is a key factor that affects the flow regime of hydraulic jump in the basin. However, the specific depth at which the water cushion is considered as “shallow” has not be stated clearly for now, and only conceptual description is provided. This paper attempts to specify the best water cushion depth based on the flow regime of hydraulic jump and underflow speed; namely, in case of critical hydraulic jump in the basin, the best water cushion depth is located where the minimum distance to the bottom plate of the stilling basin is 1/5~1/4 of the water cushion depth. The theoretical analysis indicates, at different inclinations of discharge chute (θ) and depth ratios of inlet (m), instead of monotonic change, the Froude number (Fr) at inlet of the stilling basin with shallow-water cushion firstly reduces and then increases as the flow velocity at discharge chute inlet (V) increases; the parameters of inflection point (critical flow velocity and critical Fr) increase as the inclinations of discharge chute (θ) and depth ratios of inlet (m) increase. Such regularity is the theoretical basis for selecting representative study cases. The reliability of the large eddy simulation calculation results are verified by a model test; in the paper, 30 cases including five different Froude numbers and six shallow-water cushion depths are selected, for calculating the hydraulic factors such as flow profile, flow regime and flow velocity in the stilling basin with shallow-water cushion; and the varying pattern between the best depth of stilling basin with shallow-water cushion (depth-to-length ratio) and the inflow Froude number is obtained which indicates that the best depth of stilling basin with shallow-water cushion varies little as the change of the Froude number before reaching the critical Froude number; however, the best depth-to-length ratio of stilling basin with shallow-water cushion increases as the Froude number increases after the critical Froude number is reached. The study results in this paper are of reference significance to design and calculation of the stilling basin with shallow-water cushion.
BRIEF REPORT | doi:10.20944/preprints202207.0189.v1
Subject: Arts & Humanities, Archaeology Keywords: water partitioning system; water towers; fountains; Pompeian Regiones
Online: 13 July 2022 (04:41:28 CEST)
Pompeii was connected to the great Serino aqueduct under the principate of Augustus. From that moment on, water became not only a precious resource for the inhabitants but also their true social indicator. It is no coincidence, in fact, that the concentration of sumptuous dwellings is in Regio VI, the district closest to the aqueduct reservoir (castellum aquae in Latin) and the one most equipped with piezometric towers, the first of the network, the ones that would never leave the decorative fountains of the peristyles dry. From this observation follows the original possibility of considering the water network a factor that contributed to designating the morphology of urban neighbourhoods and blocks.
ARTICLE | doi:10.20944/preprints202201.0281.v1
Subject: Engineering, Civil Engineering Keywords: Sana’a Region; Rainfall; Surface Water; Groundwater; Water Crisis
Online: 19 January 2022 (16:07:08 CET)
Yemen is a water-scarce country with inadequate fresh water and considerable groundwater depletion, as well as a lack of adequate surface water. The study region is considered an arid region, and there is insufficient water to meet the needs of the region's yearly population growth rate of 4 %. This study aims to assess the water resources in the Sana'a region and to identify the current water situation and forecast for the future. Rainfall changes spatial and temporal in very few quantities and an annual average of 267 mm. Water harvesting facilities are entirely filled by 75% of the total water facilities in the rainy seasons. The groundwater level in Sana’a Basin decreases about 6-8 meters annually due to the increase in the number of wells, the abundance of abstraction, and the lack of recharge. The amount of abstraction exceeds 400% of the recharge in the Sana'a basin. The water per capita is 70 - 85 m³ annually. It is an abstraction from the aquifers by private wells. The crop cultivated area decreased from 184217 hectares in 2007 to 122583 hectares in 2018 due to lack of water. The sewage treatment plant treats 18.25 Mm³ annually, with less than 70 % efficiency. The water deficit is about 500 to 723 Mm³ annually; it is an abstraction from the aquifers by private wells. The current water situation in the Sana'a region is catastrophic, and the planning and management must ensure a water balance in the future.
ARTICLE | doi:10.20944/preprints202108.0217.v1
Online: 10 August 2021 (09:11:15 CEST)
Hotel water systems colonized with Legionella spp. have been the source of travel-associated Legionnaires’ disease and cases, clusters or outbreaks continue to be reported worldwide each year. A total of 132 hotels linked with travel-associated Legionnaires’ disease, as reported through the European Legionnaires’ Disease Surveillance Network, were inspected and tested for Legionella spp. during 2000–2019 by the public health authorities of the island of Crete (Greece). A total of 3,311 samples were collected: 1,885 (56.93%) from cold water supply systems, 1,387 (41.89%) from hot water supply systems, 37 (1.12%) were swab samples and two (0.06%) were soil. Of those, 685 (20.69%), were collected from 83 (62.89%) hotels, testing positive (≥ 50CFU/L) for Legionella pneumophila) serogroups 1-10, 12-14 and non-pneumophila species (L. anisa, L. erythra, L. tusconensis, L. taurinensis, L. birminghamensis, L. rubrilucens, L. londiniesis, L. oakridgensis, L. santicrusis, L. brunensis, L. maceacherii). The most frequently isolated L. pneumophila serogroups were 1 (27.92%) and 3 (17.08%). Significantly higher isolation rates were obtained from hot water supply systems (25.96%) versus cold water systems (16.98%) and swab samples (13.51%). A Relative Risk (R.R.) > 1 (p < 0.0001) was calculated for hot water temperature <55 °C (R.R.: 4.43), chlorine concentrations <0.2 mg/L (R.R.: 2.69), star rating <4 (R.R.: 1.73) and absence of Water Safety Plan implementation (R.R.: 1.57).
ARTICLE | doi:10.20944/preprints202009.0252.v1
Subject: Life Sciences, Other Keywords: Water saving; Irrigation; Water productivity; Grain yield; Rice
Online: 11 September 2020 (09:22:02 CEST)
Tanzania with 945 million hectares of land area and annual rainfall of 300 mm on 67% of its territorial land is considered as a semi-dry region in the world. Rice production in Tanzania needs to be increased to feed a growing population, whereas water for irrigation is getting scarce. One way to decrease water consumption in paddy fields is to change the irrigation regime for rice production and to replace continuous flooding with alternate wetting and drying. In order to investigate the effect of different regimes of irrigation and nitrogen fertilizer on yield and water productivity of hybrid rice, two greenhouse pot experiments comprising soils from upland and lowland production ecologies were conducted at Sokoine University of Agriculture, Tanzania during crop seasons of 2019. The experiment was arranged in split plots based on randomized completely block design with 3 replications. Water regimes were the main factor comparing continuous flooding (CF) and alternate wetting and drying (AWD) with nitrogen fertilizer levels as the sub-factor including absolute control , 0, 60, 90, 120 and 150 kg/ha. Alternate wetting and drying (AWD) improved water productivity in both upland and lowland production ecologies compared to CF. AWD increased yield under lowland production by 13.3% while in upland there was 18.5% decrease in yield. The average water use varied from 31.5 to 84 L pot-1 under upland trials, while in lowland trials it was 36 to 82.3 L. Higher yield and lower water application led to an increase in WP varying from 1.2 to 1.8 kg cm-3 under upland trials, and 0.6 to 1.5 kg cm-3 under lowland trials. The variation in water productivity among treatments was mainly due to the differences in the yield, water and nitrogen levels used in the production process. Both sets of trials recorded water saving up to 34.3% and 17.3% under lowland and upland trials, respectively. Under upland trials, the yield varied from 39.9 to 124.1 g pot-1 and in lowland trials yield ranged from 20.6 to 118.2 g pot-1 representing paddy rice. The measurements showed that less water can be used to produce more crops under alternative rice growing practices. The results are important for water-scarce areas, providing useful information to policy makers, farmers, agricultural departments, and water management boards in devising future climate-smart adaptation and mitigation strategies.
ARTICLE | doi:10.20944/preprints201907.0339.v2
Subject: Engineering, Civil Engineering Keywords: Water Quality Index; irrigation water quality; Tabriz Aquifer
Online: 9 September 2019 (08:42:20 CEST)
The key goal of the current study was to determine suitable areas of water pumping for drinking and agricultural harvest in Tabriz aquifer, located in East Azerbaijan province, northwest Iran. In the study area, groundwater is the key foundation of water for drinking and farming requirements. Groundwater compatibility study was conducted by analyzing Electrical conductivity (EC), Total dissolved solids (TDS), Chloride (Cl), Calcium (Ca), Magnesium (Mg), Sodium (Na), Potassium (K), Sulfate (SO4), Total hardness (TH), Bicarbonate (HCO3), pH, carbonate (CO3) and Sodium Adsorption Ratio (SAR) obtained from 39 wells in the period of 2003 to 2014. For this purpose, the Water Quality Index (WQI) and irrigation water quality (IWQ) index were utilized. The WQI index zoning exposed that the groundwater of the study area for drinking purposes is categorized as excellent, good and poor water. Most drinking water harvested for urban and rural areas are in the class of 'excellent water'. The results revealed that about 37 percent (296 km2) of groundwater has high compatibility, and 63 percent of the study area (495 km2) has average compatibility for agricultural purposes. The trend of IWQ and WQI indexes demonstrates that the groundwater is getting worse over the time.
ARTICLE | doi:10.20944/preprints201901.0200.v1
Subject: Earth Sciences, Environmental Sciences Keywords: water availability; shale gas; water sustainability; Weiyuan play
Online: 21 January 2019 (08:59:29 CET)
Innovations and improvements in hydraulic fracturing and horizontal well technologies have contributed to the success of the shale gas industry; however, the industry is also challenged by freshwater use and environmental health issues. Increasing water impact makes precise quantification of water consumption important. The objective in this study was to better understand water sustainability and availability of the projected shale gas from 2018 to 2030 in the Weiyuan play, China. The water footprint framework was used to quantify the potential water use and environmental impacts on different time scales. The results showed that the water use per well ranged from 11351.3 to 60664.73 m3, with a median of 36013.94 m3, totaling ~3.44 Mm3 for 97 wells. Yearly evaluation results showed that the gray water footprint was the main contributor and accounted for 83.82% to 96.76%, which was dependent on different scenarios of treatment percentages. The monthly environmental impact results indicated that the annual streamflow statistics were more likely to prevent water withdrawal. Water quality issues may be alleviated through recycling and retreatment measures that improve current waste water management strategies. Resource regulators should manage their water resources by matching water demand to water availability or replenishment.
ARTICLE | doi:10.20944/preprints201810.0279.v1
Subject: Engineering, Civil Engineering Keywords: reservoirs; water allocation; water scarcity; alert volume; governance
Online: 15 October 2018 (05:13:54 CEST)
The Brazilian water legislation advocates that some uses have priority over others, but this aspect has never been clearly addressed, generating conflicts. Water authorities usually refer to hydrological models to justify their decisions on water allocation. However, a significant group of stakeholders does not feel qualified to discuss these models and is, therefore, excluded from the decision process. We hereby propose a hydrologically robust method to correlate water uses with their respective reservoir alert volumes, which should empower the less formally educated stakeholders. The method consists of: (i) generating the water discharge versus reliability curve, using a stochastic approach; (ii) generating the withdrawal discharge versus alert volume family of curves, using a water-balance approach; (iii) calibrating the key parameter T using field data; and (iv) associating each water use with its alert volume. We have applied the method to four of the largest reservoirs (2.10³ - 2.10² hm³) in the semi-arid Ceará State. The results indicate that low-priority water uses should be rationalized when the reservoir volume is below 20%; whereas uses with very high priority should start rationalization when it is below 11%. These hydrological guidelines should help enhance water governance among non-specialist stakeholders in water-scarce and reservoir-dependent regions.
ARTICLE | doi:10.20944/preprints201706.0045.v1
Subject: Social Sciences, Other Keywords: Virtual water; Agriculture; Staples; Water resources per capita
Online: 8 June 2017 (18:06:51 CEST)
Lack of water resources in Iran, especially in recent years, has faced the agricultural sector as the most important consumer of water resources, with serious challenges. In Iran, the agricultural sector accounted for more than 90% of water consumption. However, the focus on domestic production and self-sufficiency policy in staples (wheat, barley, maize and rice) has been emphasized in general agriculture's policy. This study was conducted to estimate the imported virtual water from the imports of basic products in Iran using defined indicators during 1961-2013. Also this study investigated the possibility of achieving self-sufficiency due to the limited water resources in Iran. The results of this study showed with the increase in cereal imports, virtual water imports from 0.28 billion cubic meters in 1961 increased to 17.6 billion cubic meters in 2013 and on average about 60% of virtual water imports in strategic products is related to wheat imports during the past 53 years. Other products in cereal (barley, maize and rice) are also indicative of the general trend of increasing imports of virtual water in development plans. The estimated long-run elasticity of virtual water imports in the cereal group compared with the country's water resources also showed that with a one percent reduction in renewable water resources of the country, the virtual water import in the main cereal group will increase equivalent to 2.89 percent and the determination coefficient more than 90 percent also confirms this negative relationship. According to this result and the emphasis on the fact that renewable water resources per capita in the country is falling increasingly, it cannot be expected that domestic production could compensate for the imports of the cereal group and virtual water imports with current technology, without increasing the water productivity and without additional harm to water resources.
ARTICLE | doi:10.20944/preprints202205.0283.v1
Subject: Social Sciences, Economics Keywords: energy policy; energy economics; renewable energy; fossil energy; nuclear energy; hybrid energy; teaching
Online: 23 May 2022 (03:33:09 CEST)
Issues related to safe and abundant energy production have been prominent in recent years. This is particularly tr ue when society considers how to increase the quality of life by providing low-cost energy to citizens. A significant concern of the Gulf Cooperation Council (GCC) relates to the environmental effects of energy production and energy use associated with climate change. Efforts to reduce fossil fuel use and increase the use of renewable energy, together with the price volatility of fossil fuels, have seriously impacted the economics of many of the oil-producing countries, particularly the Gulf States, which has led to efforts to make their economies more diverse and less dependent on oil production.
ARTICLE | doi:10.20944/preprints201701.0001.v1
Subject: Earth Sciences, Environmental Sciences Keywords: hyperspectral remote sensing; water absorption feature; vegetation water content; 970 nm; CVWI; vegetation water indices
Online: 2 January 2017 (10:23:30 CET)
Although the water absorption feature (WAF) at 970 nm is not very well-defined, it may be used alongside other indices to estimate the canopy water content. The individual performance of a number of existing vegetation water content (VWC) indices against the WAF is assessed using linear regression model. We developed a new Combined Vegetation Water Index (CVWI) by merging indices to boost the weak absorption feature. CVWI showed a promise in assessing the vegetation water status derived from the 970 nm absorption wavelength. CVWI was able to differentiate two groups of dataset when regressed against the absorption feature. CVWI could be seen as an easy and robust method for vegetation water content studies using hyperspectral field data.
ARTICLE | doi:10.20944/preprints202212.0096.v1
Subject: Chemistry, Electrochemistry Keywords: bipolar membrane; mathematical modelling; water dissociation; water-splitting kinetics
Online: 6 December 2022 (09:39:51 CET)
A model is proposed that describes the transfer of ions and the process of water dissociation in a system with a bipolar membrane and adjacent diffusion layers. The model considers the transfer of four types of ions: the cation and anion of salt and the products of water dissociation – hydrogen and hydroxyl ions. To describe the process of water dissociation, a model for accelerating the dissociation reaction with the participation of ionogenic groups of the membrane is adopted. The boundary value problem is solved numerically using COMSOL® Multiphysics 5.5 software. An analysis of the results of a numerical experiment shows that, at least in a symmetric electromembrane system, there is a kinetic limitation of the water dissociation process, apparently associated with the occurrence of water recombination reaction at the of the bipolar region. An interpretation of the entropy factor (β) is given as a characteristic length which shows the possibility of an ion that appeared as a result of the water dissociation reaction to be removed from the reaction zone without participating in recombination reactions.
ARTICLE | doi:10.20944/preprints202110.0157.v1
Subject: Chemistry, Chemical Engineering Keywords: Adsorption; Cane Papyrus; Oily water; Produced water; Isotherm; Kinetic
Online: 11 October 2021 (11:53:37 CEST)
High quantities of wastewater produced from producing natural gas and oil from the aquifer, which called produced water. The produced water was comprised of dissolved solids, suspended solids, emulsified oil, and organic and inorganic compounds. That should be treated it's before disposal because it causes harm to the environment. This study takes the produced water from the southern Iraqi oilfield drilling company to adsorption by the Cane papyrus as natural and low-cost adsorbent. The analysis completed by using Fourier transforms infrared spectroscopy, EDX spectra and Scanning Electron Microscopic (SEM) for Cane papyrus. Investigating the effect of many parameters such as adsorbent dosage, temperature, solution pH, mixer speed and contact time. The Langmuir, Freundlich, Temkin and Harkins-Henderson isotherm models were tested, the results were 0.998,0.966, 0.931 and 0.966 respectively. The Langmuir model was more suitable described the adsorption process than the other models. The kinetics results were, 0.984 for Pseudo-first-order, 0.938 for Pseudo-second order is, 0.979 for Intra particle diffusion study and 0.912 for the Elovich model, the Pseudo-first-order kinetic equation best described the kinetics of the reaction. The thermodynamics study effect temperature changes on the thermodynamic parameters such as standard free energy change (∆G°), standard enthalpy change (∆H°) and standard entropy change (∆S°). The experimental data obtained demonstrated that Cane papyrus is a suitable adsorbent for removing oil from produced water.
ARTICLE | doi:10.20944/preprints202011.0500.v1
Subject: Engineering, Automotive Engineering Keywords: water vapour; bound water; diffusion; adsorption; wood; sorption experiment
Online: 19 November 2020 (10:34:08 CET)
The paper presents a model of moisture transport in wood taking into account diffusion and the accompanying adsorption of water vapour through the skeleton. A two-parameter form of the source term was proposed, depending on the distance of the current mass concentration of bound water from the equilibrium state. The tests on cubic samples with a side of 2 cm were carried out which allowed to determine the coefficients of the proposed model on the basis of the reverse method. The tests were performed for pine, larch, oak and ash in all directions of orthotropy. Also the tests on thin samples were performed to verify the source term.
ARTICLE | doi:10.20944/preprints202009.0691.v1
Subject: Engineering, Civil Engineering Keywords: water allocation; planning; river/reservoir systems; water availability modeling
Online: 28 September 2020 (16:55:27 CEST)
Effective water resources management requires assessments of water availability within a framework of complex institutions and infrastructure employed to manage extremely variable stream flow shared by numerous often competing water users and diverse types of use. The Water Rights Analysis Package (WRAP) modeling system is fundamental to water allocation and planning in the state of Texas in the United States. Integration of environmental flow standards into both the modeling system and comprehensive statewide water management is a high priority for continuing research and development. The public domain WRAP software and documentation are generalized for application any place in the world. Lessons learned in developing and implementing the modeling system in Texas are relevant worldwide. The modeling system combines: (1) detailed simulation of water right systems, interstate compacts, international treaties, federal/state/local agreements, and operations of storage and conveyance facilities; (2) simulation of river system hydrology; and (3) statistical frequency and reliability analyses. The continually evolving modeling system has been implemented in Texas by a water management community that includes the state legislature, planning and regulatory agencies, river authorities, water districts, cities, industries, engineering consulting firms, and university researchers. The shared modeling system contributes significantly to integration of water allocation, planning, system operations, and research.
ARTICLE | doi:10.20944/preprints201707.0012.v1
Subject: Medicine & Pharmacology, Nutrition Keywords: diabetes; water intake; mineral water; magnesium; bicarbonate; review; prevention
Online: 6 July 2017 (18:12:04 CEST)
To address the question whether there is evidence that drinking water in general or mineral water in particular is effective in preventing diabetes; we performed a literature search of randomized controlled trials (PubMed). The search resulted in very few trials (N = 9) investigating this topic: one trial investigates the effect of increasing water consumption on glycemic control in diabetic patients; two trials investigate the effect of drinking water with a meal in diabetic patients; while six trials compare the effect of mineral rich water with that of low mineralized water on glucose metabolism in healthy subjects. There is evidence that increasing water consumption can improve glucose metabolism and randomized controlled trials with mineral water suggest that waters containing relevant amounts of magnesium can exert an additional effect. The role of bicarbonate; which is present in all the mineral waters used in the trials; will be discussed. Future research needs to investigate the effect of mineral water in prediabetic individuals or individuals with impaired glycemic control.
REVIEW | doi:10.20944/preprints202102.0236.v1
Subject: Keywords: goods and services; water-limited area; plant-water relationship; Soil water resource use limit by plants; Soil Water Carrying Capacity for Vegetation
Online: 9 February 2021 (11:49:54 CET)
The goods and services produced by forest and vegetation ecology system is the power by which human society can be promoted fast in high-quality and sustainable way. With the increase of population and economic development in water-limited regions, there is an increasing demand for the quantity and variety of forest vegetation ecosystem products and services. To meet the demands of this situation, most of the original forest has changed into farmland, non-native forest and grass land. As a result, water-plant relationship changed from equilibrium to non-equilibrium, which led to soil drought, soil degradation and vegetation decline in dry years or waste of soil water in rainy years in most of water-limited regions. In order to solve the questions and realize the sustainable utilization of soil water resources and the high quality and sustainable development of social economy, it is necessary to apply the utilization limit theory of soil water resources by plants and the theory of soil water carrying capacity for vegetation to adjust the relationship between plant growth and soil moisture to obtain the maximum yield and benefit of vegetation and serve high-quality and sustainable development.
HYPOTHESIS | doi:10.20944/preprints202301.0294.v1
Subject: Physical Sciences, Astronomy & Astrophysics Keywords: Dark Energy, Entropic Energy, Suprathermal Energy
Online: 17 January 2023 (01:53:59 CET)
The Universe at last scattering is locally treated as an unbound gas. The internal kinetic energy of the gas effectively constitutes a scalar energy field. The gas’s adiabatic expansion is entropic, giving repulsive entropic pressure. Gas kinetic energy is converted into entropic energy gain (63%) and isoentropic work against gravity (37%) at a constant 63:37 ratio. A three-term expression of the gas’s Hubble parameter is derived and found to be exclusively dependent on its mass density. At last scattering, this model gives a Hubble constant that is 125% of the value found from the ΛCDM model. After partition of Universal mass into the cosmic web of galaxies and the intergalactic medium (IGM), expansion came mostly from the IGM, presently comprising about 84% of total Universal mass and 90% of its volume. The onset of star formation within the cosmic web increased the IGM’s kinetic energy through the action of starlight, giving free electrons as an additional repository. Many of these free electrons are suprathermal. Suprathermal energy from both electrons and protons comprises about half of the IGM’s total kinetic energy and is expressed in the ΛCDM model as “dark energy” Λ. Entropic pressure derives from thermodynamic laws not found within general relativity.
ARTICLE | doi:10.20944/preprints202301.0464.v1
Subject: Biology, Forestry Keywords: Adsorption water movement; adsorption hypothesis; plant long-distance water transport; thermodynamic water movement; not-hydraulic movement
Online: 26 January 2023 (03:02:38 CET)
Ad- and desorption forces move water in living xylem/wood from the root to the leaf thermodynamically. The doctrine of plant water transport, the so-called cohesion- or cohesion-tension theory, postulates however that the process is physically based on a hydraulic fluid flow with negative pressure in water conducting tubes originating from the leaves. Lower pressure (suction) driven volume flow is physically a branch of mechanics. Moisture absorbed from the soil via the root is thought to be pulled up the stem by the leaves in continuous and tensioned threads of water. It is assumed that the hydraulic Hagen/Poiseuille flow law, derived for tubes, applies in the xylem. In a textbook of botany you can find the opinion: "Just as the pipes of a water pipe supply necessary water to each household, leaf nerves supply water and nutrient salts to each individual cell.” (Translated from German). Many plant physiologists consider this hydraulic principle to be correct, but it does not remain unchallenged. Doubts are repeatedly expressed. The question arises: How does water transport actually take place? It is shown how the diffusive/adsorption transport principle works. The partial dehydration (desorption) of the plant, driven by the diffusive process of transpiration, forms a combined concentration and adsorption-site gradient for water in the xylem matrix. Especially with open stomata the lowest moisture concentration and the highest number of adsorption-sites for water (sites with free van der Waals forces), can be found in the mesophyll cell walls at the liquid/vapor boundary in the leaf. The water taken up by the root moves spontaneously in the direction of this boundary and can thus partially or completely compensate for the existing concentration- and adsorption-site- differences for water. Thus, a thermodynamic overlapping diffusive/adsorptive movement of moisture along the stationary xylem/wood takes place. After the introduction and a review of some controversies with cohesion theory, the physiology of the processes associated with long-distance water displacement is mentioned below. A thermodynamic adsorption hypothesis of the natural water transport in plants, based on known facts, is presented.
ARTICLE | doi:10.20944/preprints201909.0145.v1
Subject: Engineering, Civil Engineering Keywords: decentralized water systems; cluster approach; intra-cluster homogeneity; Water Supply Systems (WSS); Urban Water Systems (UWS)
Online: 14 September 2019 (19:33:09 CEST)
Abstract: Current models in design of urban water management systems and their corresponding infrastructure using centralized designs have commonly failed from the perspective of cost effectiveness and inability to adapt to the future changes. These challenges are driving cities towards using decentralized systems. While there is great consensus on the benefits of decentralization; currently no methods exist which guide decision-makers to define the optimal boundaries of decentralized water systems. A new clustering methodology and tool to decentralize water supply systems (WSS) into small and adaptable units is presented. The tool includes two major components: (i) minimization of the distance from source to consumer by assigning demand to the closest water source, and (ii) maximization of the intra-cluster homogeneity by defining the cluster boundaries such that the variation in population density, land use, socio-economic level, and topography within the cluster is minimized. The methodology and tool are applied to Arua Town in Uganda. Four random cluster scenarios and a centralized system were created and compared with the optimal clustered WSS. It was observed that the operational cost of the four cluster scenarios is up to 13.9 % higher than the optimal, and the centralized system is 26.6% higher than the optimal clustered WSS, consequently verifying the efficacy of the proposed method to determine an optimal cluster boundary for WSS. In addition, optimal homogeneous clusters improve efficiency by encouraging reuse of wastewater and stormwater within a cluster and by minimizing leakage through reduced pressure variations.
ARTICLE | doi:10.20944/preprints201906.0222.v1
Subject: Social Sciences, Geography Keywords: water consumption; water metabolism; tourism destination; resilience; non-conventional water resources; sustainable tourism; overtourism; shortage; Spain
Online: 22 June 2019 (11:52:42 CEST)
Tourism, and particularly residential tourism, has led to a change in the urban and demographic model of towns along the European Mediterranean coastline. Water as a limited and limiting resource for the growth of tourism is a popular topic in the scientific literature. However, the incorporation of non-conventional resources (desalination) has meant, in theory, that this limitation has been overcome. The aims of this paper are: a) to identify the different tourism models implanted in this territory and describe them from the point of view of their consumption of water in the demand cycle from 2002 to 2017; b) analyse the hydrosocial cycle, highlighting the measures aimed at satisfying water demand; and c) identify the limitations associated with these hydrosocial systems. To this end, different types of information will be processed, and various complex indicators produced. The results show the importance that demand management and the use of desalinated water in increasing the resilience of this territory to aridity. However, this has generated other problems associated with a tsunami of construction and the continuity of a non-sustainable territorial model.
ARTICLE | doi:10.20944/preprints202002.0054.v1
Subject: Keywords: energy poverty; primary energy; renewable energy; distributed generation; energy storage
Online: 5 February 2020 (03:31:29 CET)
Following an updated outlook of global energy production and utilization, we show through selected examples from both developing and developed countries how distributed generation from renewable energy sources, and from solar energy in particular, is the key solution to ending energy poverty across the world. Guidelines aimed at policy makers suggest a systems view of energy that will be instrumental in guiding the transition from fossil fuels to combustion-free renewable energy for all energy end uses.
ARTICLE | doi:10.20944/preprints201710.0108.v1
Subject: Earth Sciences, Environmental Sciences Keywords: Variance Inflation Factor; VIF; multiple regression; Landsat; Austin; Lady Bird Lake; water quality; environmental factor; energy flux; urban runoff
Online: 17 October 2017 (03:38:28 CEST)
A simple approach to enable water-management agencies employing free data to achieve the goal of using a single set of predictive equations for water-quality retrievals with satisfactory accuracy is proposed. Multiple regression-derived equations based on surface reflectance, band ratios, and environmental factors as predictor variables for concentrations of Total Suspended Solids (TSS), Total Nitrogen (TN), and Total Phosphorus (TP) were derived using a hybrid forward-selection method that considers Variance Inflation Factor (VIF) in the forward-selection process. Landsat TM, ETM+, and OLI/TIRS images were jointly utilized with environmental factors, such as wind speed and water surface temperature, to derive the single set of equations. The coefficients of determination of the best-fitting resultant equations varied from 0.62 to 0.79. Among all chosen predictor variables, ratio of reflectance of visible red (Band 3 for Landsat TM and ETM+, or Band 4 for Landsat OLI/TIRS) to visible blue (Band 1 for Landsat TM and ETM+, or Band 2 for Landsat OLI/TIRS) has a strong influence on the predictive power for TSS retrieval. Environmental factors including wind speed, remote sensing-derived water surface temperature, solar altitude, and time difference (in days) between the image acquisition and water sampling were found important in water-quality parameter estimation.
REVIEW | doi:10.20944/preprints202209.0214.v1
Subject: Life Sciences, Other Keywords: Drinking water; potable water; public health surveillance; quality control; government.
Online: 15 September 2022 (02:17:24 CEST)
This study identified and mapped worldwide surveillance actions and initiatives of drinking water quality implemented by government agencies or public health services. The scoping review was conducted between July 2021 and August 2022 based on the Joanna Briggs Institute. The search was performed in relevant databases and grey literature; 49 studies were obtained. Quantitative variables were presented as absolute and relative frequencies, while qualitative variables were analyzed using the IRaMuTeQ software. The actions developed worldwide and their impacts and results provided four thematic classes: (1) assessment of coverage, accessibility, quantity, and drinking water quality in routine and emergency situations; (2) analysis of physical-chemical and microbiological parameters in public supply networks or alternative water supply solutions; (3) identification of household water contamination, communication, and education with the community; (4) and investigation of water-borne disease outbreaks. Preliminary results were shared with stakeholders to favor early knowledge dissemination.
ARTICLE | doi:10.20944/preprints202107.0378.v1
Subject: Earth Sciences, Atmospheric Science Keywords: water quality; outdoor sports; dissolved oxygen; stagnant water; cable ski
Online: 16 July 2021 (14:36:47 CEST)
Abstract: The concept of sustainability applied to sports activities means ensuring that the economic benefits brought about by their development are not obtained at the expense of causing ecological damage or interference in local cultural habits. A cable-ski is a nautical ski system whereby a motorboat is substituted by a cable traction system powered by an electric motor. The effect on the quality of the water in those places that can boast cable-ski facilities has been described in cold freshwater lakes. Objective: Our purpose was to study the evolution of water quality in a ten-year period after the installation of a cable-ski facility in a warm, salted, semi-stagnant pond. Material and Method: Review of the data gathered from the routine test carried out by the Laboratory of the Council of Alcúdia from 2010 to 2019 Results: The levels of dissolved oxygen have increased, being significantly higher in the period 2016 – 2019 than in that of 2010 – 2015. The turbidity of the water has also seen a reduction in the second period with respect to the first. Conclusion: It seems that cable-ski improves the quality of water even warm, high-conductivity, semi-stagnant conditions
ARTICLE | doi:10.20944/preprints202010.0230.v1
Subject: Social Sciences, Accounting Keywords: water framework directive; European Union; The Netherlands; water law; politics
Online: 12 October 2020 (11:41:08 CEST)
This article discusses the implementation of the Water Framework Directive (WFD) in the Netherlands and intends to show how law and politics combine in river basin management. Initially, the implementation of the WFD in the Netherlands was approached as a technical and administrative issue, handled by water quality and ecology experts, but in 2003 this approach was broken open by the agricultural sector, who were worried about stricter regulation. Subsequently, the environmental objectives of the WFD were set as low as possible and they are not used in authorising individual projects. Yet, in 2015 of the European Court of Justice determined that the environmental objectives have binding effect and that Member States have to refuse authorisation for projects that endanger the achievement of these objectives. In the future, the European Court of Justice and national courts may force the Dutch government to change its approach. They may only do so because and as long as they enjoy sufficient social and political support and function relatively independently. The article concludes that, to understand river basin management fully, one has to open up the black box of water law and become a kind of water lawyer.
ARTICLE | doi:10.20944/preprints202008.0721.v2
Online: 12 October 2020 (10:15:32 CEST)
Rainwater harvesting could be an optional water source to fulfil the emergency water demand in different setups. The aim was to assess if the rainwater harvesting potential for households and selected institutions were sufficient to satisfy the emergency water demand for the prevention of COVID-19 in Dilla town, Southern, Ethiopia. Rain water harvesting potential for households and selected institutions were quantified using 17 years’ worth of rainfall data from Ethiopian Metrology Agency. With an average annual rainfall of 1464 mm, households with 40 and 100 m2 roof sizes have a potential to harvest between 15.71-31.15 m3 and 41.73-82.73 m3 of water using Maximum Error Estimate. Meanwhile 7.2-39.7 m3 and 19.11-105.35 m3 of water can be harvested from the same roof sizes using Coefficient of Variation for calculation. Considering mean monthly rainfall, the health centres and Dilla University can attain 45.7% and 77% of their emergency water demand, while the rest of the selected institutions in Dilla Town can attain more than 100 % of their demand using only rainwater. Rain water can be an alternative water source for the town in the fight against COVID-19.
ARTICLE | doi:10.20944/preprints201904.0173.v1
Subject: Engineering, General Engineering Keywords: capacitive level sensor; water level monitoring; maintaining constant water level
Online: 15 April 2019 (12:57:40 CEST)
This paper presents a device for measuring and maintaining the constant water level in a tank. The device uses a capacity sensor to measure the water level. The sensor has a DC voltage output proportional to the water level in the tank. This voltage can be used in other automation too. The water level, in percentages, is displayed on a vu meter with 8 LEDs. The circuit for maintaining the constant level consists in a comparator with hysteresis. The level of the water is adjustable, using a reference voltage from a potentiometer (marked in percentages). The level of the water is compared with the prescribed level and the difference between them commands the start/stop of the water pump which supplies the tank through a relay. The device is powered by 220 V and is isolated from the environment.
ARTICLE | doi:10.20944/preprints201811.0393.v1
Subject: Social Sciences, Political Science Keywords: water-rich area; water rights transaction; trading need; Taihu Basin
Online: 16 November 2018 (09:24:58 CET)
To alleviate the contradiction between the increasing demand for water and the shortage of resources and to provide a favorable institutional environment for water rights trading, the Chinese government has strengthened the top-level design of water management system. However, the water-rich regions (southern regions of China) have good water resource endowment and a surplus of total water consumption indicators. Does this mean that there is no incentive and no need to conduct water rights trading in these regions? Through the investigation of water rights circulation cases in the Taihu Basin, a typical water-rich region of China, we established the existence of trading demand and some difficulties in conducting transactions. This paper argues that the needs of trading include alleviating the water gap in regional development, solving the water demand for large new projects, coordinating trans-jurisdiction water disputes. The plight of trading includes the lack of awareness, irregular process, excessive administrative intervention, and imperfect trading system.
ARTICLE | doi:10.20944/preprints202012.0025.v1
Subject: Physical Sciences, Acoustics Keywords: plasma-liquid interactions; water electrospray; aerosol microdroplet; bulk water, plasma-activated water; Henry’s law solubility; ozone; hydrogen peroxide
Online: 1 December 2020 (13:16:22 CET)
Production and transport of reactive species through plasma-liquid interactions plays a significant role in multiple applications in biomedicine, environment, and agriculture. We experimentally investigated the transport mechanisms of hydrogen peroxide H2O2 and ozone O3, as the typical plasma species, into water. We measured the solvation of gaseous H2O2 and O3 in airflow into water bulk vs. electrosprayed microdroplets while changing the gas and water flow rates, applied voltage that determines the gas-liquid interface area, and treatment time. The solvation rate of H2O2 and O3 increased with the treatment time and the gas-liquid interface area. The total surface area of the electrosprayed microdroplets was larger than that of the bulk, but their lifetime was much shorter. We estimated that only microdroplets with diameters below ~ 40 µm could achieve the saturation by O3 during their lifetime, while the saturation by H2O2 was impossible due to its depletion from air. Besides the short-lived flying microdroplets, the longer-lived bottom microdroplets substantially contributed to H2O2 and O3 solvation in water electrospray. This study contributes to a better understanding of the gaseous H2O2 and O3 transport into water as a function of different parameters and will lead to design optimization of the plasma-liquid interaction systems.
ARTICLE | doi:10.20944/preprints201801.0116.v1
Subject: Engineering, Energy & Fuel Technology Keywords: solar energy; BIPV; energy transition; energy efficiency; photovoltaics
Online: 12 January 2018 (10:23:45 CET)
Large-scale integration of solar energy technologies in Rome’s built environment epitomizes the needed general adoption of distributed generation via functionalization of buildings of all size and end use across the world, to become active energy generators and no longer energy users only. This paper identifies selected technology solutions and critical policy and educational initiatives to effectively achieve within the next decade (2018-2027) the widespread uptake of decentralized solar energy systems in the built environment on a global scale.
ARTICLE | doi:10.20944/preprints202103.0521.v1
Subject: Physical Sciences, Acoustics Keywords: Two-layer fluid; shear flow; air-water interface; surface tension; vortex sheet; Kelvin-Helmholtz instability; negative-energy wave; modulation instability
Online: 22 March 2021 (11:26:38 CET)
The modulation instability of surface capillary-gravity water waves is analysed in a shear flow model with a tangential discontinuity of velocity. It is assumed that air blows along the surface of the water with a uniform profile in the vertical direction. Such a model, despite its simplicity, plays an important role in hydrodynamics as the reference model for investigating basic physical phenomena of wave-current interactions and acquiring insights into a series of complex phenomena. In certain cases where the wavelength of interfacial perturbations is much bigger than the width of the shear fow profile, the model with the tangential discontinuity in the velocity is adequate for describing physical phenomena at least within limited spatial and temporal frameworks. A detailed analysis of the air-flow conditions under which modulation instability sets in is presented. It is also shown that the interfacial waves are subject to dissipative or radiative instability when negativeenergy waves appear at the interface.
ARTICLE | doi:10.20944/preprints202205.0406.v1
Subject: Engineering, Energy & Fuel Technology Keywords: nuclear energy; renewable energy; fossil energy; small modular reactors; resilience; hybrid energy
Online: 31 May 2022 (03:13:28 CEST)
Small modular reactors (SMR) (<300 MW) offer a potentially attractive nuclear energy option for the middle-east region (MER). Currently, the MER uses a significant amount of fossil fuel to process heat applications such as water desalination and in petroleum refineries and chemical plants, besides generating electricity. SMR technologies represent an opportunity to meet future energy demand in the MER. This paper discusses issues related to the future development and use of SMR technology in nuclear-renewable hybrid energy systems for application in the middle east. SMRs have also been examined as part of a resilient hybrid energy system that combines nuclear energy with renewable energy and traditional fossil energy to produce chemicals, fuels, and electricity. This paper presents the results of a techno-economic analysis of a Nuclear-Renewable-Conventional Hybrid Energy System. The paper concludes that SMR technology will be an essential feature of future hybrid energy systems for the MER.
Subject: Engineering, Energy & Fuel Technology Keywords: Energy System Modelling; Energy Optimization; Energy Simulation; Multi Energy Systems Simulator (MESS)
Online: 21 July 2021 (14:50:24 CEST)
Energy system modelling is an essential practice to assist a set of heterogeneous stakeholders in the process of defining an effective and efficient energy transition. From the analysis of a set of open source energy system models, it has emerged that most models employ an approach directed at finding the optimal solution for a given set of constraints. On the contrary, a simulation model is a representation of a system that is used to reproduce and understand its behaviour under given conditions, without seeking an optimal solution. Given the lack of simulation models that are also fully open source, in this paper a new open source energy system model is presented. The developed tool, called Multi Energy Systems Simulator (MESS), is a modular, multi-node model that allows to investigate non optimal solutions by simulating the energy system. The model has been built having in mind urban level analyses. However, each node can represent larger regions allowing wider spatial scales to be be represented as well. MESS is capable of performing analysis on systems composed by multiple energy carriers (e.g. electricity, heat, fuels). In this work, the tool’s features will be presented by a comparison between MESS itself and an optimization model, in order to analyze and highlight the differences between the two approaches, the potentialities of a simulation tool and possible areas for further development.
ARTICLE | doi:10.20944/preprints202210.0062.v1
Subject: Earth Sciences, Environmental Sciences Keywords: goods and services; water-limited area; plant water relationship; Soil water resource use limit by plants; Soil Water Carrying Capacity for Vegetation; critical period of plant-water relationship regulation; high-quality Sustainable development
Online: 6 October 2022 (10:03:29 CEST)
The goods and services produced by forest vegetation ecosystem are the driving force for the rapid, high-quality and sustainable development of human society. In history, with the increase of population and economic development, there is an increasing demand for the quantity and variety of forest vegetation ecosystem products and services in a country or a region. To meet the demands, most of the original forest has become farmland, plantation and grass and crops land. As a result, the plant water relationship changed from equilibrium to non-equilibrium, which easily led to soil drought, soil degradation and vegetation decline in dry years or waste of soil water in rainy years in most of water-limited regions. In order to solve the question and realize the sustainable utilization of soil water resources and the high-quality sustainable development of forest, it is necessary to apply the limit theory of plant utilization of soil water resources and the vegetation carrying capacity theory in the critical period of plant-water relationship regulation to adjust the relationship between plant growth and soil moisture to obtain the maximum yield and benefit and realize high-quality and sustainable development.
ARTICLE | doi:10.20944/preprints202212.0456.v1
Subject: Arts & Humanities, Archaeology Keywords: Chagga; water infrastructures; water management; sustainable farming; social complexity; community collaboration
Online: 23 December 2022 (09:00:41 CET)
Since the second half of the second millennium AD, water management among the Chagga people of Kilimanjaro in Tanzania has involved community collaboration in the construction, ownership and management of water infrastructure. Chagga settlement on the lower slopes of Kilimanjaro transformed the landscape significantly to reflect an agrarian society characterised by decentralised forms of socio-political and economic organisation. Such organization involved conception, construction, and post-construction management of water distribution systems, constituting high-level socio-political complexity. The study employs ethnography, archaeological surveys and GIS to document water infrastructures on the lower slopes of Kilimanjaro. We conclude that community collaboration was key in management of the water infrastructure and by extension, agriculture, which sustained Chagga and chiefdoms for centuries.
ARTICLE | doi:10.20944/preprints202212.0174.v1
Subject: Materials Science, General Materials Science Keywords: high-pressure water jet; high-pressure abrasive water- jet; rock processing
Online: 9 December 2022 (09:22:30 CET)
Rocks are materials with a wide variety of structures and properties. These can be unprocessed conglomerates of conglomerated minerals as well as crystallized outcrop or metamorphic rocks. Their processing, especially shaping, poses many technological difficulties. Therefore, it is very important to answer the question of how these natural materials yield to high-pressure water jet and abrasive water. It is equally important to determine the effect of key process parameters such as pressure, water nozzle diameter and feed rate on cutting efficiency. The first two parameters determine the water output and power of the jet, while the third determines the jet erosion time per unit volume of material. Their interdependence, using appropriate evaluation indicators, allows to determine the energy intensity of processing and directions for its minimization.
CASE REPORT | doi:10.20944/preprints202210.0345.v1
Subject: Engineering, Other Keywords: Urinal; Passive Infrared (PIR); Water Conservation; Water efficiency; Campus; building management
Online: 24 October 2022 (03:18:04 CEST)
This study looks at the application of delayed action Passive InfraRed (PIR) sensors in the control of water use for urinal flushing. In this we briefly review the literature on urinal controls before reviewing four different approaches to PIR urinal controls. Existing literature discusses some of the pros and cons of different types of urinal control. However, the literature doesn’t consider the marked differences that can occur within individual approaches, based on the way controls operate. This study was initiated at the University of Surrey during 2019 following a water saving audit, in an attempt to bring down what had been identified as one of the largest users of water. This paper therefore aims to identify the most effective way to reduce water consumption of urinal systems, through retro-fitting PIR control systems within the variety of settings found across university campuses. This paper also reviews the different reductions achieved over periods of different levels of use, linked to term time, holidays, Covid-19 related lockdowns, and the ‘new normal’. It found that grouped delayed action flushing was the most effective form of urinal control for reducing water use. The delayed action, grouped PIR sensors, achieved between, a 59-64% adjusted reduction against the control group during non-Covid19 periods, and a 35% reduction against the control group during lockdowns.
ARTICLE | doi:10.20944/preprints202206.0128.v1
Subject: Physical Sciences, Applied Physics Keywords: Reynold number; high-density water; molecular dynamics; water model; percolation theory
Online: 8 June 2022 (12:24:33 CEST)
Turbulence is a fluid dynamic problem refractory to mathematical treatment. Examining a theoretical model of liquid water flowing in a cylinder at different Raleigh numbers, we propose a novel approach to elucidate the first stages of turbulent flows. The weakly bonded molecular assemblies of liquid water form a fluctuating branched polymer in which every micro-cluster displays different density. Against the common view of liquid water as an incompressible and continuous fluid, we suggest that the occurrence of transient local aggregates could be able to generate the vortices and eddies that are the hallmarks of turbulence. We quantify the local changes in velocity, diameter and density required to engender “obstacles” to the average flow. Then, we show how these microstructures, equipped with different Raleigh numbers and characterized by high percolation index, could generate boundary layers that contribute to micro-vortices production. We conclude that the genesis of turbulence cannot be assessed in terms of collective phenomena, rather is sustained, among many other factors, by the underrated microscopic inhomogeneities of fluids like liquid water.
ARTICLE | doi:10.20944/preprints201910.0186.v1
Subject: Earth Sciences, Environmental Sciences Keywords: stable water isotopes; deuterium; oxygen-18; soil water; fine root system
Online: 16 October 2019 (10:32:02 CEST)
Stable isotope concentrations in the soil, rain and ground water have been used to trace the water extraction zones of plants in different environments. The need to identify the plant water use by plants in afforestation programs to control desertification increases the importance of sap water partitioning of plants in sand dune areas. However, the introduction of new plant covers exerts pressure on the water resources and can affect the local soil water conditions. In this study, we analyzed the isotope concentrations in rain, soil, sap, and ground water after the summer of 2010. Two experimental plots established in the Hailiutu catchment (Shaanxi province, northwest China) were selected to gather the water samples between September and October 2010. One plot is dominated by Salix bushes (Salix psammophila C. Wang \& Chang Y. Yang) and the other by the tree species Willow (Salix matsudana Koidz.). The total precipitation at the experimental site was 401 mm/yr during 2010, while 88.7 mm was collected in total for the period September to October. Willow trees transpired 12.82 kg/d being almost three times larger than Salix shrubs (4.57 kg/d). Despite the transpiration rates of both plant species and the few rain events in the region, the soil water beneath the plant covers is not depleted. Stable isotope signature of soil water beneath both covers shows the fractionation front in Salix at 20 cm depth and at Willow at 40 cm depth. However, soil water signature is closer to the groundwater than the collected rain water.
ARTICLE | doi:10.20944/preprints201901.0260.v1
Subject: Earth Sciences, Environmental Sciences Keywords: reservoir; water quality indexes; GEVORG index; Armenian Water Quality Index; Armenia
Online: 25 January 2019 (15:03:46 CET)
In this article, the quality of water in the reservoirs of Lake Arpi, Lake Yerevan, Akhuryan, Azat, Aparan and Kechut was estimated with usage of the Armenian Water Quality Index. It was established that in the waters of reservoirs the the maximum permissible concentration of copper, vanadium, aluminum, chromium, manganese, iron, NH4+ and NO2- regularly increases. The following computational algorithm was used for determination of the Armenian Water Quality Index values: to determine the number of cases of MPC excess of i-substance or indicator of water –n; to estimate the total amount of cases of the maximum permissible concentration (N) – N = ∑n; to computes log2N, nlog2n and ∑nlog2n; to determine geoecological syntropy (I) and entropy (H): I = ∑ nlog2n/N and H = log2N – I. Then, Geo-Ecological Evolving Organized index index was determined: G = H/I. Further, the total amount multiplicity of MAC exceedances was estimated: (M) - M=∑m and log2M was computed. Finally, Armenian Water Quality Index was obtained: AWQI = G + 0.1log2M. It was established that the Armenian Water Qquality Index showed a linear dependence on the Water Contamination Index, the Specific Combinatory Water Quality Index, the Geo-Ecological Evolving Organized index and an inverse dependence on the Canadian Water Quality Index.