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841.
Benito-Garzón Marta Fady Bruno Davi Hendrik Vizcaíno-Palomar Natalia Fernández-Manjarrés Juan 《Regional Environmental Change》2018,18(5):1427-1437
Regional Environmental Change - The adaptation of social-ecological systems such as managed forests depends largely on decisions taken by forest managers who must choose among a wide range of... 相似文献
842.
Márcia Maria Guedes Alcoforado de Moraes Anne Biewald Ana Cristina Guimarães Carneiro Gerald Norbert Souza da Silva Alexander Popp Hermann Lotze-Campen 《Regional Environmental Change》2018,18(7):1943-1955
Economic values of water for the main Public Irrigation Schemes in the sub-middle region of the São Francisco River Basin, in northeastern Brazil, are determined in this study using an integration of a global agro-economic land and water use (MAgPIE) with a local economic model (Positive Mathematical Programming). As in the latter, the water values depend on the crops grown, and as Brazilian agriculture is strongly influenced by the global market, we used a regionalized version of the global model adapted to the region in order to simulate the crop land use, which is in turn determined by changes in global demand, trade barriers, and climate. The allocation of sugarcane and fruit crops projected with climate change by the global model, showed an impact on the average yields and on the water costs in the main schemes resulting in changes in the water values locally. The economic values for all schemes in the baseline year were higher than the water prices established for agricultural use in the basin. In the future, these water values will be higher in all the schemes. The highest water values currently and in the future were identified in municipalities with a significant proportion of area growing irrigated sugarcane. Being aware of current water values of each user in a baseline year and in a projected future under global climate and socioeconomic changes, decision makers should improve water allocation policies at local scale, in order to avoid conflicts and unsustainable development in the future. 相似文献
843.
Kristopher B. Karnauskas Jeffrey P. Donnelly Kevin J. Anchukaitis 《Regional Environmental Change》2018,18(8):2273-2282
Small island developing states (SIDS) face multiple threats from anthropogenic climate change, including potential changes in freshwater resource availability. Due to a mismatch in spatial scale between SIDS landforms and the horizontal resolution of global climate models (GCMs), SIDS are mostly unaccounted for in GCMs that are used to make future projections of global climate change and its regional impacts. Specific approaches are required to address this gap between broad-scale model projections and regional, policy-relevant outcomes. Here, we apply a recently developed methodology that circumvents the GCM limitation of coarse resolution in order to project future changes in aridity on small islands. These climate projections are combined with independent population projections associated with shared socioeconomic pathways (SSPs) to evaluate overall changes in freshwater stress in SIDS at warming levels of 1.5 and 2 °C above pre-industrial levels. While we find that future population growth will dominate changes in projected freshwater stress especially toward the end of the century, projected changes in aridity are found to compound freshwater stress for the vast majority of SIDS. For several SIDS, particularly across the Caribbean region, a substantial fraction (~?25%) of the large overall freshwater stress projected under 2 °C at 2030 can be avoided by limiting global warming to 1.5 °C. Our findings add to a growing body of literature on the difference in climate impacts between 1.5 and 2 °C and underscore the need for regionally specific analysis. 相似文献
844.
Jorge Cunha Manuel Lopes Nunes Fátima Lima 《Environment, Development and Sustainability》2018,20(1):163-179
Due to the high rates of energy consumption and its impact on environment over the last decades, policy decision-makers are increasingly recognising the need to take actions that allow to address problems associated with the deployment of non-renewable resources and climate changes. One field of action has been the promotion of measures that contribute to improve energy efficiency of countries. The purpose of this study is to identify the main factors explaining changes in energy efficiency applying the multiplicative Log Mean Divisia Index decomposition method for a set of countries (Portugal, UK, Brazil and China) with different socio-economic background and energy mix. The results show that overall energy efficiency trends display different patterns between countries and the same happens within each country from a sectoral perspective. Major drivers of improvements of overall energy efficiency were the intensity effect and the affluence effect, whereas the driver that hampered those improvements was the energy consumption per capita. Some policy implications derived from the results achieved are: policy decision-makers should support measures that promote the adoption of energy-saving technologies resulting from new technological developments; policy measures should be directed to raise awareness of end-users regarding energy efficiency and energy conservation efforts; policy measures promoting economic growth through the development (or expansion) of sectors of activity that consume less energy can also be implemented; finally, policy instruments may also be used to reduce the costs of implementing energy efficiency and energy-saving measures to households and firms. 相似文献
845.
Although studies on environmental conflicts have engaged with the subject of violence, a multidimensional approach has been lacking. Using data from 95 environmental conflicts in Central America, we show how different forms of violence appear and overlap. We focus on direct, structural, cultural, slow, and ecological forms of violence. Results suggest that the common understanding of violence in environmental conflicts as a direct event in time and space is only the tip of the iceberg and that violence can reach not only environmental defenders, but also communities, nature, and the sustainability of their relations. 相似文献
846.
Barbro Ulén Mats Larsbo Johannes Koestel Qarin Hellner Maria Blomberg Pia Geranmayeh 《Ambio》2018,47(1):114-123
Assessing mitigation of phosphorus (P) leaching from subsurface drainage systems is challenging due to high spatial and temporal variation in leaching. Mean measured total P leaching from a clayey soil in an eight-year study period (four replicates per treatment) was (kg ha?1 year?1): 1.21 from shallow autumn tillage (ShT), 0.84 from unfertilised fallow (UF), 0.81 from conventional autumn ploughing (CT) and 0.57 from structure liming (SL–CT). Treatment was not significant using Richards–Baker flow index or a distance factor as covariate (p = 0.084 and 0.057). A tendency for lower leaching was obtained comparing SL-CT with ShT (p adjusted = 0.060 and 0.009 respectively). A combination of measures adapted to drainage conditions and clay content in different parts of the field is proposed since P leaching was approximately halved from an adjacent field (4.3 ha) in a three-year post-period compared with a three-year pre-period for structure liming the entire field and drainage system renovation plus structure lime drain backfilling. 相似文献
847.
Erik Jeppesen Martin Appelt Kirsten Hastrup Bjarne Grønnow Anders Mosbech John P. Smol Thomas A. Davidson 《Ambio》2018,47(2):296-309
Based on lake sediment data, archaeological findings, and historical records, we describe rapid transformations, resilience and resistance in societies and ecosystems, and their interactions in the past in the North Water area related to changes in climate and historical events. Examples are the formation of the polynya itself and the early arrival of people, ca. 4500 years ago, and later major human immigrations (different societies, cultural encounters, or abandonment) from other regions in the Arctic. While the early immigrations had relatively modest and localised effect on the ecosystem, the later-incoming culture in the early thirteenth century was marked by extensive migrations into and out of the area and abrupt shifts in hunting technologies. This has had long-lasting consequences for the local lake ecosystems. Large natural transformations in the ecosystems have also occurred over relatively short time periods related to changes in the polynya. Finally, we discuss the future perspectives for the North Water area given the many threats, but also opportunities. 相似文献
848.
Jean-Baptiste E. Thomas Jonas Nordström Emma Risén Maria E. Malmström Fredrik Gröndahl 《Ambio》2018,47(4):398-409
Efforts are on the way on the Swedish West Coast to develop the capacity for cultivation of marine resources, notably of kelps. Given that this is a region of great natural and national heritage, public opposition to marine developments has been identified as a possible risk factor. This survey thus sought to shed light on awareness levels, perceptions of different types of aquaculture and on reactions to a scenario depicting future aquaculture developments on the West Coast. When asked about their general opinions of aquaculture, respondents tended to be favourable though a majority chose neutral responses. On the whole, respondents were favourable to the depicted scenario. Finally, it was found that the high-awareness group tended to be more supportive than the low or medium-awareness groups, hinting at the benefits of increasing awareness to reduce public aversion and to support a sustainable development of aquaculture on the Swedish West Coast. 相似文献
849.
Jian Liu Peter J. A. Kleinman Helena Aronsson Don Flaten Richard W. McDowell Marianne Bechmann Douglas B. Beegle Timothy P. Robinson Ray B. Bryant Hongbin Liu Andrew N. Sharpley Tamie L. Veith 《Ambio》2018,47(6):657-670
Winter manure application elevates nutrient losses and impairment of water quality as compared to manure applications in other seasons. In conjunction with reviewing global distribution of animal densities, we reviewed worldwide mandatory regulations and voluntary guidelines on efforts to reduce off-site nutrient losses associated with winter manure applications. Most of the developed countries implement regulations or guidelines to restrict winter manure application, which range from a regulative ban to guidelines based upon weather and field management conditions. In contrast, developing countries lack such official directives, despite an increasing animal production industry and concern over water quality. An analysis of five case studies reveals that directives are derived from a common rationale to reduce off-site manure nutrient losses, but they are also affected by local socio-economic and biophysical considerations. Successful programs combine site-specific management strategies along with expansion of manure storage to offer farmers greater flexibility in winter manure management. 相似文献
850.
D. Luján-Rhenals Z. Shi S. C. Ricke 《Journal of environmental science and health. Part. B》2018,53(1):12-17
Soybean meal (SBM) is a product generated from the manufacture of soybean oil and has the potential for use as a source of fermentable sugars for ethanol production or as a protein source for animal feeds. Knowing the levels of nitrogen available from ammonium is a necessary element of the ethanolic fermentation process while identifying the levels of essential amino acids such as lysine is important in determining usage as a feed source. As such the purpose of this study was to quantify total nitrogen and ammonium in the liquid fraction of hydrolyzed SBM and to evaluate total and bioavailable lysine in the solid fraction of the hydrolyzed SBM. The effects of acid concentration, cellulase and β-glucosidase on total and ammonium nitrogen were studied with analysis indicating that higher acid concentrations increased nitrogen compounds with ammonium concentrations ranging from 0.20 to 1.24 g L?1 while enzymatic treatments did not significantly increase nitrogen levels. Total and bioavailable lysine was quantified by use of an auxotrophic gfpmut3 E.coli whole-cell bioassay organism incapable of lysine biosynthesis. Acid and enzymatic treatments were applied with lysine bioavailability increasing from a base of 82% for untreated SBM to up to 97%. Our results demonstrated that SBM has the potential to serve in ethanolic fermentation and as an optimal source essential amino acid lysine. 相似文献