103 research outputs found
Organic agricultural practice enhances arbuscular mycorrhizal symbiosis in correspondence to soil warming and altered precipitation patterns
Organic agricultural practice enhances arbuscular mycorrhizal symbiosis in correspondence to soil warming and altered precipitation patterns
Climate change and mountain water resources: overview and recommendations for research, management and policy
Mountains are essential sources of freshwater for our world, but their role in global water resources could well be significantly altered by climate change. How well do we understand these potential changes today, and what are implications for water resources management, climate change adaptation, and evolving water policy? To answer above questions, we have examined 11 case study regions with the goal of providing a global overview, identifying research gaps and formulating recommendations for research, management and policy. <br><br> After setting the scene regarding water stress, water management capacity and scientific capacity in our case study regions, we examine the state of knowledge in water resources from a highland-lowland viewpoint, focusing on mountain areas on the one hand and the adjacent lowland areas on the other hand. Based on this review, research priorities are identified, including precipitation, snow water equivalent, soil parameters, evapotranspiration and sublimation, groundwater as well as enhanced warming and feedback mechanisms. In addition, the importance of environmental monitoring at high altitudes is highlighted. We then make recommendations how advancements in the management of mountain water resources under climate change could be achieved in the fields of research, water resources management and policy as well as through better interaction between these fields. <br><br> We conclude that effective management of mountain water resources urgently requires more detailed regional studies and more reliable scenario projections, and that research on mountain water resources must become more integrative by linking relevant disciplines. In addition, the knowledge exchange between managers and researchers must be improved and oriented towards long-term continuous interaction
Trends in extreme weather events in Europe: implications for national and European Union adaptation strategies
This report, based on a comprehensive collection of scientific data from the last 20 years, provides a rallying call for Europeâs policy makers to come together to devise common strategies to help mitigate the physical, human and economic costs of the rising number of extreme weather events in Europe, such as extreme heat and cold, extremes of precipitation, storms, winds and surges, and drought. Highlights refer to the nature of the evidence for climate-driven changes in extreme weather in the past, the potential impact of further climate change in altering the pattern of these extremes, and possible adaptation strategies for dealing with extreme weather impacts.
It first provides information on extreme weather events and trends in recent decades as well as related impacts upon society. It is followed by an introduction to the scientific background on global warming and weather extremes, and the projections of future trends of meteorological extreme events that emerge from climate models under various scenarios of future greenhouse gas emissions. Finally, approaches to adaptation are introduced and recommendations provided. Readers wishing to obtain full source details for the figures, tables and references are recommended to consult the full report, which also includes more detailed analyses of the climatic conditions in various sub-regions of the EU
Testing the paradox of enrichment along a land use gradient in a multitrophic aboveground and belowground community
In the light of ongoing land use changes, it is important to understand how multitrophic communities perform at different land use intensities. The paradox of enrichment predicts that fertilization leads to destabilization and extinction of predator-prey systems. We tested this prediction for a land use intensity gradient from natural to highly fertilized agricultural ecosystems. We included multiple aboveground and belowground trophic levels and land use-dependent searching efficiencies of insects. To overcome logistic constraints of field experiments, we used a successfully validated simulation model to investigate plant responses to removal of herbivores and their enemies. Consistent with our predictions, instability measured by herbivore-induced plant mortality increased with increasing land use intensity. Simultaneously, the balance between herbivores and natural enemies turned increasingly towards herbivore dominance and natural enemy failure. Under natural conditions, there were more frequently significant effects of belowground herbivores and their natural enemies on plant performance, whereas there were more aboveground effects in agroecosystems. This result was partly due to the âboom-bustâ behavior of the shoot herbivore population. Plant responses to herbivore or natural enemy removal were much more abrupt than the imposed smooth land use intensity gradient. This may be due to the presence of multiple trophic levels aboveground and belowground. Our model suggests that destabilization and extinction are more likely to occur in agroecosystems than in natural communities, but the shape of the relationship is nonlinear under the influence of multiple trophic interactions.
Impact of climate change on hydrological regimes and water resource management in the Rhine basinâ,
Abstract. The International Commission for the Hydrology of the Rhine basin (CHR) has carried out a research project to assess the impact of climate change on the river flow conditions in the Rhine basin. Along a bottom-up line, different detailed hydrological models with hourly and daily time steps have been developed for representative sub-catchments of the Rhine basin. Along a topdown line, a water balance model for the entire Rhine basin has been developed, which calculates monthly discharges and which was tested on the scale of the major tributaries of the Rhine. Using this set of models, the effects of climate change on the discharge regime in different parts of the Rhine basin were calculated using the results of UKHI and XCCC GCM-experiments. All models indicate the same trends in the changes: higher winter discharge as a result of intensified snow-melt and increased winter precipitation, and lower summer discharge due to the reduced winter snow storage and an increase of evapotranspiration. When the results are considered in more detail, however, several differences show up. These can firstly be attributed to different physical characteristics of the studied areas, but different spatial and temporal scales used in the modelling and different representations of several hydrological processes (e.g., evapotranspiration, snow melt) are responsible for the differences found as well. Climate change can affect various socio-economic sectors. Higher temperatures may threaten winter tourism in the lower winter sport areas. The hydrological changes will increase flood risk during winter, whilst low flows during summer will adversely affect inland navigation, and reduce water availability for agriculture and industry. Balancing the required actions against economic cost and the existing uncertainties in the climate change scenarios, a policy of 'noregret and flexibility' in water management planning and design is recommended, where anticipatory adaptive measures in response to climate change impacts are undertaken in combination with ongoing activities. Present address
Impact of solid-electrolyte interphase reformation on capacity loss in silicon-based lithium-ion batteries
High-density silicon composite anodes show large volume changes upon charging/discharging triggering the reformation of the solid electrolyte interface (SEI), an interface initially formed at the silicon surface. The question remains how the reformation process and accompanied material evolution, in particular for industrial up-scalable cells, impacts cell performance. Here, we develop a correlated workflow incorporating X-ray microscopy, field-emission scanning electron microscopy tomography, elemental imaging and deep learning-based microstructure quantification suitable to witness the structural and chemical progression of the silicon and SEI reformation upon cycling. The nanometer-sized SEI layer evolves into a micron-sized silicon electrolyte composite structure at prolonged cycles. Experimental-informed electrochemical modelling endorses an underutilisation of the active material due to the silicon electrolyte composite growth affecting the capacity. A chemo-mechanical model is used to analyse the stability of the SEI/silicon reaction front and to investigate the effects of material properties on the stability that can affect the capacity loss
Production bias in cultural evolution: An examination of cubic dice variation in experimental and archaeological contexts
Similar artifact function and conformism to social norms are two models commonly proposed to explain why ancient people shared a particular form of material culture. We propose an additional model for explaining such similarity, production bias, which focuses on interactions between raw materials and the production of material culture. By way of modern replication experiments and a survey of ancient examples, we use dice to exemplify production bias and discuss how it can be recognized in the archaeological record. Although there are 15 possible configurations for cubic dice, all of equal function, only three are common in the archaeological record. Replication experiments show that one is the result of production bias, and is differentially produced by novice dice-makers. The other two are the byproduct of conformist cultural transmission processes. A similar result holds for dot patterns, or how dots are placed with respect to one another to represent a particular number
Are exergames promoting mobility an attractive alternative to conventional self-regulated exercises for elderly people in a rehabilitation setting? Study protocol of a randomized controlled trial
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