ARTICLE | doi:10.20944/preprints202305.2100.v1
Subject: Engineering, Energy And Fuel Technology Keywords: European Union; renewable energy; bioenergy; woody biomass; carbon neutrality
Online: 30 May 2023 (09:44:04 CEST)
The EU has set the ambitious target of raising the share of EU energy consumption produced from renewable resources to 32% by 2030 with a target of climate neutrality by 2050. The aim of this paper is to assess the role of biomass usage in the context of these targets. The paper identifies progress made between 2013–2022 by focusing on a selection of EU countries. The largest bio-energy increments of 130PJ, 77PJ and 60PJ were reported for Poland, Sweden, and the Nether-lands. This study valuates the crucial role in co-generation and heat in EU regions, with biomass usage between 55-80% of the combined heat and power (CHP) energy in Nordic countries. The future perspectives for bioenergy based on EU policies, biomass resources and technical issues were addressed. The EU possess around 9% of the global biomass supply, ensuring a certain level of biomass resource dependence. Thus, the biomass usage demand in energy production, non-energy sectors and transport is expected to rise leading to increments of 13%-76% on biomass imports. It appears that bioenergy development is mostly limited by economic issues and uneven support for bioenergy in different EU countries as well as environmental issues. The study shows a promising and sustainable potential of bioenergy in the EU as a renewable energy source while minimizing negative impacts on the environment and the economy. By 2050, liquid biofuels are likely to be increasingly used in the transport sector. Non-energy sector usage of biomass is still in an early stage of development, except for the pulp and paper industry, and significant use of biomass in non-energy sectors seems unlikely in the near future.
ARTICLE | doi:10.20944/preprints202212.0584.v1
Subject: Biology And Life Sciences, Forestry Keywords: miRNA156; micropropagation; tree breeding; recalcitrant; woody plants; perennial plants
Online: 30 December 2022 (10:18:33 CET)
In plants, phase change from the juvenile stage to maturity is a tightly controlled process at the physiological and genetic level, which is controlled by evolutionary highly conserved microRNAs. These phase changes are more pronounced in woody plant species, but the majority of molecular genetic studies on the regulation of this transition has been done in annual model or crop species. This process is of particular significance for the in vitro propagation of woody plant species, as individuals or tissues that have undergone the transition to vegetative maturity are recalcitrant to propagation. Development of effective methodologies for silver birch vegetative propagation are required to increase the efficiency of breeding programs. Conserved miRNAs that were differentially expressed between juvenile and mature silver birch tissues were identified using high-throughput sequencing of small RNA libraries. These differentially expressed miRNAs could potentially be utilized to develop markers indicating the juvenility or maturity of silver birch explants and in vitro cultures. In addition, the obtained results will provide an insight into the molecular mechanisms regulating vegetative phase change in silver birch and other perennial woody plant species.
ARTICLE | doi:10.20944/preprints202002.0446.v1
Subject: Biology And Life Sciences, Forestry Keywords: Kafta-sheraro national park; woody species structure; regeneration status
Online: 28 February 2020 (16:24:09 CET)
The natural vegetation study was conducted in Kafta-sheraro national park (KSNP) North, Ethiopia to explore floristic composition, structure and regeneration of woody species in the home of African elephant. In the park, the above information is not well documented which is necessary for conservation. Data were collected From August to December 2018. The vegetation data were collected from 161 quadrats of size 20m×20m, 5mx5m for shrub ̸ tree, sapling and seedling respectively. Individual trees and shrubs DBH >=2.5cm and height >=2m were measured using Tape meter and Clinometer respectively. DBH, frequency, density, basal area, and IVI were used for vegetation structure. A total of 70 woody species 46 (65.7%) trees, 18 (25.7%) shrubs and 6 (8.6%) tree ̸ shrub) were identified. The total basal area and density of 79.3 m2 ha-1, and 466 ±12.8 (S.E.) individuals ha-1 were calculated for 64 woody species. Fabaceae was the most dominant family occupied 16 species (23.0%) followed by Combretaceae 8 species (11.4%). Acacia mellifera and Combretum hartmannianum were the most dominant and frequent species. Abnormal patterns of selected woody species were dominantly identified. Regenerating status all the woody plant species was categorized as “Fair” (18.75%), “Poor” (7.81 %) and “None” (73.44%). However, there is good initiation for conservation of the park; still the vegetation of the park was threatened by firewood collection, charcoal production, fire, intensive farming, mining and over grazing. Therefore, the study area as the habitat for the population of the African elephant; the KSNP should be recommended the highest conservation priority and studied the soil seed bank of species having poor regeneration condition.
ARTICLE | doi:10.20944/preprints201703.0173.v1
Subject: Environmental And Earth Sciences, Environmental Science Keywords: land use; management; woody cover determinants; human-environment; Sahel
Online: 22 March 2017 (15:55:14 CET)
Woody vegetation in farmland acts as a carbon sink and provides ecosystem services for local people, but no macro-scale assessments of the impact of management and climate on woody cover exists for drylands. Here we make use of very high spatial resolution satellite imagery to derive wall-to-wall woody cover patterns in tropical West African drylands. In arid and semi-arid Sahel, areas of more people are associated with more trees: mean woody cover is greater in farmlands (12%) than in savannas (6%), and likewise it is higher close to villages than further away. In sub-humid savannas of West Africa, woody cover is generally above 20% and decreases with increasing population density, but remains around 15% in farmlands, independent of rainfall. In the region as a whole, rainfall, terrain and soil are the most important (80%) determinants of woody cover, while management factors play a smaller (20%) role. We conclude that agricultural expansion cannot generally be claimed to cause woody cover losses, and that observations in Sahel contradict simplistic ideas of a high negative correlation between population density and woody cover.
ARTICLE | doi:10.20944/preprints202108.0288.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: stem implanted capsule; bioherbicide; parkinsonia; woody weed; dieback; mechanical delivery
Online: 13 August 2021 (08:34:59 CEST)
An infestation of parkinsonia (Parkinsonia aculeata) located on Alexandria Station, Northern Territory, Australia was successfully treated with a bioherbicide using stem implanted capsules. The bioherbicide containing three endemic endophytic fungi (Lasiodiplodia pseudotheobromae, Macrophomina phaseolina and Neoscytalidium novaehollan-diae) is the first Australian registered woody weed bioherbicide. The product was effectively administered to the plant stems using a mechanical device, resulting in subsequent development of a dieback event, which, after a period of establishment, has moved through the adjacent untreated plant population resulting in significant decline in infestation vigour and reduced recruitment. This is the first report of large-scale management of parkinsonia by this method.
ARTICLE | doi:10.20944/preprints201810.0112.v1
Subject: Business, Economics And Management, Economics Keywords: woody biomass; Northern Great Plains; farmers and ranchers; focus groups
Online: 6 October 2018 (08:56:18 CEST)
Bioenergy produced from perennial feedstocks such as woody biomass could serve as an opportunity to strengthen local and regional economies and also jointly produce various environmental services. In order to assess the potential for biomass- based bioenergy, it’s essential to characterize the interest that potential biomass suppliers have in such an endeavor. In the U.S. Great Plains region, this largely means assessing relevant perceptions of farmers and ranchers. We conducted a series of farmer and rancher oriented focus groups in North Dakota, South Dakota, Nebraska and Kansas to qualitatively explore opinions about the role that trees can play in agriculture and interest in woody biomass systems within existing Northern Great Plains (NGP) farms and ranches. Our findings suggest that farmer and ranchers generally value the role that trees, or tree-based practices like windbreaks can play in agriculture particularly on marginal farmland in terms of conservation or crop protection. Yet relative to the potential of trees as a biomass crop there is a distinct lack of knowledge and skepticism. Farmers and ranchers also noted variable degrees of risk concern and uncertainty regarding investing in tree-based systems, as well as a number of perceived external market related constraints to integrating trees within their managed systems. Most of the participants recognized that if biomass production or an increase in tree planting and management in general were to expand in the NGP region, government programs would likely be required to provide much needed technical guidance and financial incentives. As the NGP regional bioeconomy continues to emerge and expand, private and public investment relative to niche bioenergy feedstocks such as woody biomass should address the type of information needs that farmers and ranchers have relative to integrating biomass production into existing farm and ranch systems.
ARTICLE | doi:10.20944/preprints201804.0266.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: gas exchange; leaf canopy temperature; life forms; thermography; woody vines
Online: 20 April 2018 (11:55:08 CEST)
Leaf temperature (Tleaf) influences photosynthesis and respiration. Currently, there is a growing interest on including lianas in productivity models due to their increasing abundance, and their detrimental effects on net primary productivity in tropical environments. Therefore, understanding the differences of Tleaf between lianas and trees is important for future of forest on whole ecosystem productivity. Here we determined the displayed leaf temperature (Td= Tleaf – ambient temperature) of several species of lianas and their host trees during ENSO and non-ENSO years to evaluate if the presence of lianas affects the Td of their host trees, and if leaves of lianas and their host trees exhibit differences in Td. Our results suggest that close to midday, the presence of lianas does not affect the Td of their host trees; however, lianas tend to have higher values of Td than their hosts across seasons, in both ENSO and non-ENSO years. Although lianas and trees tend to have similar physiological-temperature responses, differences in Td could lead to significant differences in rates of photosynthesis and respiration based temperature response curves. Future models should thus consider differences in leaf temperature between these life forms to achieve robust predictions of productivity.
ARTICLE | doi:10.20944/preprints201608.0154.v1
Subject: Biology And Life Sciences, Ecology, Evolution, Behavior And Systematics Keywords: carbon stock assessment; protected areas; savannas; degradation; woody vegetation; West Africa
Online: 15 August 2016 (12:06:29 CEST)
Savannas and adjacent vegetation types like gallery forests are highly valuable ecosystems contributing to several ecosystem services including carbon budgeting. Financial mechanisms such as REDD+ have provided an opportunity for developing countries to alleviate poverty through conservation of its forestry resources. For availing this opportunity carbon stock assessments are essential. Therefore, a research study at two protected areas i.e. Nazinga Game Ranch and Bontioli Nature Reserve, in Burkina Faso was conducted with the objective of assessing carbon Mg C ha-1 in aboveground biomass (AGB)dry of trees in different formations of the south-sudanian savanna in Burkina Faso, West Africa. Similarly analysis of various vegetation parameters was also conducted to understand the overall vegetation structure of these two protected areas. For estimating AGBdry, existing allometric equation for dry tropical woody vegetation types was used. The Importance Value Index (IVI) and Family Importance Value (FIV) were estimated through standard procedures. Various linear and non-linear regression analyses were conducted to test the relationships between carbon and other parameters such as DBH, height and basal area (BA). The results showed that both sites collectively contain mean carbon of 3.41 ± 4.98 Mg C ha-1. Amongst different vegetation types, gallery forests recorded the highest mean carbon of 9.38 ± 6.90 Mg C ha-1. The highest IVI of 115.56 at Nazinga Game Ranch was recorded for Anogeissus leiocarpa. Similarly, highest IVI of 98.59 was recorded for Mitragyna inermis at Bontioli Nature Reserve. The highest FIV was recorded for Combretaceae for both of the sites. To our knowledge, this was the first study conducted to assess the carbon stocks at the two protected areas in southern Burkina Faso. The study therefore was an attempt for addressing the knowledge gap particularly on carbon stocks of protected savannas. It could serve as a baseline for carbon stocks for future initiatives such as payment for environmental services and REDD+ at these areas.
ARTICLE | doi:10.20944/preprints202303.0487.v1
Subject: Environmental And Earth Sciences, Environmental Science Keywords: woody crop classification; Sentinel-2; random forest; crop phenology; olive; orchard; vineyards; Mediterranean
Online: 28 March 2023 (11:19:29 CEST)
The characteristics of the Sentinel-2 mission with a decametric resolution and frequent acquisitions allow to improve the identification of crops. The majority of the studies on crop classification using RS were targeted at herbaceous and gramineous crop classes while fewer results were obtained on woody crops which present a strong variability in management practices that make their identification difficult. Thus, this study aimed to propose a rapid, accurate, and cost-effective analytical approach for the delineation of fruit orchards (OC), vineyards (VY), and olive groves (OL) in the Mediterranean (Southern France) considering two locations. A classification based on phenology metrics (PM) de-rived from temporal Sentinel-2 time series was developed to perform the classification. The PM were computed by fitting a double logistic model on temporal profiles of vegeta-tion indices to delineate OC, VY, and a DC class gathering all remaining surfaces. The generated PM were introduced in a random forest (RF) algorithm to identify woody crops across the two sites. The method was tested on different vegetation indices, the best results being obtained with the leaf area index (LAI). To delineate OL in the DC class, the tem-poral features of the green chlorophyll vegetation index (GCVI) were found to be the most appropriated with a typical drop of the signal during the mid-season (DOY 150-250). As a final result, we obtained an overall accuracy ranging from 89-96% and Kappa of 0.86-0.95 by considering each study site and year (2016-2021), separately. This accuracy is much better than applying the RF algorithm on the LAI times series, which led to a Kappa rang-ing between 0.3 and 0.52 and demonstrates the interest of using phenological traits rather than the raw time series of the RS data. The method can be well reproduced from one year to another. Moreover, it is possible to apply the classification model of a given year to an-other, keeping good accuracy. This is an interesting feature to reduce the burden of col-lecting ground truth information. On the contrary, the use of a classification model cali-brated in one site and applied to another led to a strong degradation of the classification accuracy. Woody crop phenology is dependent on site climatic conditions as well as the cultivar and management practices that can differ from one site to another.
ARTICLE | doi:10.20944/preprints202203.0084.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: drought tolerance; roadside woody vegetation; Simpson diversity; site conditions; tree mortality; tree planting initiatives
Online: 4 March 2022 (17:04:27 CET)
Long-term, multi-decade research on planted tree survival in urban settings is sparse. One understudied urban environment is highway rights-of-way (ROW), lands adjacent to high-speed, unsignalized roadways. We conducted a re-inventory of tree planting cohort in northern Illinois, U.S. on a 48 km-long highway near Chicago which were 10-, 21-, and 30-years old to evaluate long-term patterns of survival and diversity. Using each randomly selected planting site along the highway as a unit of observation and analysis, we compared the number of trees documented in record drawing to the number of trees currently alive to determine percent survival. We evaluated 224 planting sites which originally contained 2,944 trees and collected data about the planting site location. For the oldest cohort, 26% of trees were still alive in 2018 (median survival by species = 16%, Q1 = 0%, Q3 = 48%), while 31% of the 21-year-old cohort (med. = 6%, Q1 = 0%, Q3 = 47%) and 86% of the 10-year-old cohort were still alive (med. = 85%, Q1 = 74%, Q3 = 96%). The survival of the 21- and 30-year-old cohort matches urban tree survival estimates by other researchers, while the 10-year-old survival is higher than expected. The only planting location characteristic that significantly affected survival was traffic islands (areas between the highway and entrance/exit ramps). Species with low drought tolerance were less likely to be alive for the 10-year-old cohort. Waterlogging tolerant species were more likely to be alive in the 10-year-old cohort. Since some species in the 21- and 30-year-old cohorts had very low survival, the tree species richness and diversity s in study areas declined between the initial record drawings and reinventory. This study demonstrates the challenges of maintaining long-term survival and diversity in the highway ROW and emphasizes the importance of species selection.