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81.
82.
The 2015–2016 El Niño had large impacts globally. The effects were not as great as anticipated in Kenya, however, leading some commentators to call it a ‘non-event’. Our study uses a novel combination of participatory Climate Vulnerability and Capacity Analysis tools, and new and existing social and biophysical data, to analyse vulnerability to, and the multidimensional impacts of, the 2015–2016 El Niño episode in southern coastal Kenya. Using a social-ecological systems lens and a unique dataset, our study reveals impacts overlooked by conventional analysis. We show how El Niño stressors interact with and amplify existing vulnerabilities to differentially impact local ecosystems and people. The policy significance of this finding is that the development of specific national capacities to deal with El Niño events is insufficient; it will be necessary to also address local vulnerabilities to everyday and recurrent stressors and shocks to build resilience to the effects of El Niño and other extremes in climate and weather.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01321-z) contains supplementary material, which is available to authorized users.  相似文献   
83.
Between 1996 and 2002, the Swedish import of so-called yellow waste for energy recovery increased. The import mainly consisted of separated wood waste and mixes of used wood and paper and/or plastics that was combusted in district heat production plants (DHPPs). Some mixed waste was imported to waste incineration plants for energy recovery (10% of the import of yellow waste for energy recovery in 2002). The import came primarily from Germany, the Netherlands, Norway, Denmark and Finland. We identified six underlying driving forces for this recent increase of imported waste which are outlined and their interactive issues discussed. --The energy system infrastructure, which enables high energy recovery in Sweden. --The energy taxation, where high Swedish taxes on fossil fuels make relatively expensive solid biofuels the main alternative for base load production of district heat. --The quality of the waste-derived fuels, which has been higher in the exporting countries than in Sweden. --The bans on landfilling within Europe and the shortage of waste treatment capacity. --Taxes on waste management in Europe. --Gate fee differences between exporting countries and Sweden. In the future, the overall strength of these driving forces will probably be weakened. A Swedish tax on waste incineration is being investigated. In other European countries, the ambition to reach the Kyoto targets and increase the renewable electricity production could improve the competitiveness of waste-derived fuels in comparison with fossil fuels. Swedish DHPPs using waste-derived fuels will experience higher costs after the Waste Incineration Directive is fully implemented. The uncertainty about European waste generation and treatment capacity, however, might have a large influence on the future gate fees and thus also on the yellow waste import into Sweden.  相似文献   
84.
When central governments decentralize natural resource management (NRM), they often retain an interest in the local efforts and provide funding for them. Such outside investments can serve an important role in moving community-based efforts forward. At the same time, they can represent risks to the community if government resources are not stable over time. Our focus in this article is on the effects of withdrawal of government resources from community-based NRM. A critical question is how to build institutional capacity to carry on when the government funding runs out. This study compares institutional survival and coping strategies used by community-based project organizations in two different contexts, India and the United States. Despite higher links to livelihoods, community participation, and private benefits, efforts in the Indian cases exhibited lower survival rates than did those in the U.S. cases. Successful coping strategies in the U.S. context often involved tapping into existing institutions and resources. In the Indian context, successful coping strategies often involved building broad community support for the projects and creatively finding additional funding sources. On the other hand, the lack of local community interest, due to the top-down development approach and sometimes narrow benefit distribution, often challenged organizational survival and project maintenance.  相似文献   
85.
This paper studies the effect of food web structure on the extinction risk of species. We examine 793 different six-species food web structures with different number, position and strength of trophic links and expose them to stochasticity in a model with Lotka–Volterra predator–prey dynamics. The characteristics of species (intrinsic rates of increase as well as intraspecific density dependence) are held constant, but the interactions with other species and characteristics of the food web are varied.  相似文献   
86.
Carbendazim sorption-desorption in Vietnamese soils   总被引:2,自引:0,他引:2  
Four Vietnamese soils (denoted AG, CT, ST and TG) which differed with respect to pH (pH 2.9-5.4), clay (17-50%) and organic matter (0.3-9.8%) content, were selected for sorption and desorption studies of carbendazim using the batch equilibration technique. Sorption increased with increasing organic carbon (OC) and clay content. Kd values for carbendazim sorption on AG, CT, ST, TG soils at initial concentration of 20 microg/g were 12.5, 127, 8.1 and 9.6 ml/g, respectively. The OC partition coefficients (Koc) for AG, CT, ST and TG were 1140, 1300, 2700 and 960 ml/g, respectively. Carbendazim was strongly sorbed and the binding was less reversible in the acid sulfate soil (CT), than in the other soils. The CT soil had both the highest OC content (9.8%) and the highest clay content (49.8%). The influence of pH on carbendazim sorption was studied in the ST and CT soils. Sorption of carbendazim by the sandy ST soil (OC 0.3%; clay content 26.3%) increased as the pH decreased, while sorption of carbendazim by the CT soil decreased as pH decreased.  相似文献   
87.
Nonpoint source (NPS) pollution has emerged as the largest threat to water quality in the United States, influencing policy makers and resource managers to direct more attention toward NPS prevention and remediation. In response, the United States Environmental Protection Agency (USEPA) spent more than $204 million in fiscal year (FY) 2006 on the Clean Water Act’s Section 319 program to combat NPS pollution, much of it on the development and implementation of watershed-based plans. State governments have also increasingly allocated financial and technical resources to collaborative watershed efforts within their own borders to fight NPS pollution. With increased collaboration among the federal government, states, and citizens to combat NPS pollution, more information is needed to understand how public resources are being used, by whom, and for what, and what policy changes might improve effectiveness. Analysis from a 50-state study suggests that, in addition to the average 35% of all Section 319 funds per state that are passed on to collaborative watershed groups, 35 states have provided financial assistance beyond Section 319 funding to support collaborative watershed initiatives. State programs frequently provide technical assistance and training, in addition to financial resources, to encourage collaborative partnerships. Such assistance is typically granted in exchange for requirements to generate a watershed action plan and/or follow a mutually agreed upon work plan to address NPS pollution. Program managers indicated a need for greater fiscal resources and flexibility to achieve water quality goals.  相似文献   
88.
Citizen Participation in Collaborative Watershed Partnerships   总被引:1,自引:1,他引:0  
Collaborative efforts are increasingly being used to address complex environmental problems, both in the United States and abroad. This is especially true in the growing field of collaborative watershed management, where diverse stakeholders work together to develop and advance water-quality goals. Active citizen participation is viewed as a key component, yet groups often struggle to attract and maintain citizen engagement. This study examined citizen participation behavior in collaborative watershed partnerships by way of a written survey administered to citizen members of 12 collaborative watershed groups in Ohio. Results for the determination of who joins such groups were consistent with the dominant-status model of participation because group members were not demographically representative of the broader community. The dominant-status model, however, does not explain which members are more likely to actively participate in group activities. Instead, individual characteristics, including political activity, knowledge, and comfort in sharing opinions with others, were positively correlated with active participation. In addition, group characteristics, including government-based membership, rural location, perceptions of open communication, perceptions that the group has enough technical support to accomplish its goals, and perceived homogeneity of participant opinions, were positively correlated with active participation. Overall, many group members did not actively participate in group activities.  相似文献   
89.
Snow samples were collected near crossroads in Novi Sad, Serbia, during December 2009 to assess metal concentrations (Ca, K, Zn, Fe, Cu, Mn, Al, Pb and Na), fine particle distribution and pH value. The filtered samples of melted snow were analysed, with a focus on particles smaller than a few μm. The most common values of the frequency number distribution curve were either in the range of 0.05-0.07 μm or one order of magnitude higher (0.2-0.5 μm). At examined locations metal concentrations varied from 0.0004 mg L−1 for Pb to 18.9 mg L−1 for Na. Besides Na, which mostly originated from de-icing salt, Ca is found to be the most abundant element in snow indicating the dominant influence of natural factors on snow chemistry. No significant difference was found in concentration of the elements at locations near crossroads with either low or high traffic volume, except for Na and Zn.To investigate how metals were related a correlation analysis was done for the concentrations of metals and with respect to the particle size distribution parameters and pH values. The major influence on the fine particle volume (mass) was concluded to be due to the elements from anthropogenic sources. This conclusion was based on the significant positive correlation between Fe, Zn and Al and the fine particle volume based distribution parameters.  相似文献   
90.
Jan J  Sovcikova E  Kocan A  Wsolova L  Trnovec T 《Chemosphere》2007,67(9):S350-S354
The effects of long-term exposure to polychlorinated biphenyls (PCBs) on developmental dental defects of deciduous and permanent teeth in children in eastern Slovakia, where PCBs from a chemical plant manufacturing Delors contaminated the surrounding district were evaluated. Four hundred and thirtytwo children, lifelong residents, aged 8-9 years were examined. Children's caries susceptibility and gingival health was assessed by standard dental indices, and developmental enamel defects by the FDI index. Data from the PCBRISK project data set and questionnaires completed by the parents provided information on exposure and various confounding factors. The proportion of teeth with different types and extensions of developmental enamel defects correlated with serum PCB concentration. The proportion of deciduous teeth affected with enamel defects was significantly higher in higher exposed children (chi(2)=8.35; p=0.03) according to their serum PCB concentration (group 0: <200; group 1: 200-600; group 2: >600 ng PCBs g(-1) serum lipids). The proportion of permanent teeth affected with any enamel defect was significantly higher in higher exposed children (chi2=7.237; p=0.027). Furthermore, the extent of the enamel defects was also greater (chi2=10.714; p=0.005). In multivariate linear regression analysis PCB exposure was significantly related to developmental enamel defects of permanent teeth only. No associations between PCB exposure and caries susceptibility, gingival health or number of teeth were observed. This study demonstrated a dose-response relationship between PCB exposure and developmental enamel defects of permanent teeth in children, the evidence for deciduous teeth was not conclusive.  相似文献   
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