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981.
982.
Social capacity building for natural hazards is a topic increasingly gaining relevance not only for so-called developing countries but also for European welfare states which are continuously challenged by the social, economic and ecological impacts of natural hazards. Following an outline of recent governance changes with regard to natural hazards, we develop a heuristic model of social capacity building by taking into account a wide range of existing expertise from different fields of research. Particular attention is paid to social vulnerability and its assessment, as well as to risk communication and risk education as specific strategies of social capacity building. We propose to distinguish between interventionist and participatory approaches, thus enabling for a better understanding of existing practices of social capacity building as well as their particular strengths and weaknesses. By way of conclusion, we encourage more research on social capacity building for natural hazards in the European context which at present is highly diverse and, at least in parts, only poorly investigated.  相似文献   
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986.
Pollinator declines have prompted efforts to assess how land-use change affects insect pollinators and pollination services in agricultural landscapes. Yet many tools to measure insect pollination services require substantial landscape-scale data and technical expertise. In expert workshops, 3 straightforward methods (desk-based method, field survey, and empirical manipulation with exclusion experiments) for rapid insect pollination assessment at site scale were developed to provide an adaptable framework that is accessible to nonspecialist with limited resources. These methods were designed for TESSA (Toolkit for Ecosystem Service Site-Based Assessment) and allow comparative assessment of pollination services at a site of conservation interest and in its most plausible alternative state (e.g., converted to agricultural land). We applied the methods at a nature reserve in the United Kingdom to estimate the value of insect pollination services provided by the reserve. The economic value of pollination services provided by the reserve ranged from US$6163 to US$11,546/year. The conversion of the reserve to arable land would provide no insect pollination services and a net annual benefit from insect-pollinated crop production of approximately $1542/year (US$24∙ha–1∙year–1). The methods had wide applicability and were readily adapted to different insect-pollinated crops: rape (Brassica napus) and beans (Vicia faba) crops. All methods were rapidly employed under a low budget. The relatively less robust methods that required fewer resources yielded higher estimates of annual insect pollination benefit.  相似文献   
987.
Environmental Geochemistry and Health - Khat (Catha edulis) chewing is widespread in the region of East Africa. Even low levels of organochlorine pesticides (OCPs) in khat could induce public...  相似文献   
988.
Although coexistence with wildlife is a key goal of conservation, little is known about it or how to study it. By coexistence we mean a sustainable though dynamic state in which humans and wildlife coadapt to sharing landscapes, where human interactions with wildlife are effectively governed to ensure wildlife populations persist in socially legitimate ways that ensure tolerable risk levels. Problems that arise from current conflict-oriented framing of human–wildlife interactions include reinforcing a human–nature dichotomy as fundamentally oppositional, suggesting coexistence requires the absence of conflict, and skewing research and management toward direct negative impacts over indirect impacts and positive aspects of living with wildlife. Human behavior toward wildlife is framed as rational calculus of costs and benefits, sidelining emotional and cultural dimensions of these interactions. Coexistence is less studied due to unfamiliarity with relevant methodologies, including qualitative methods, self-reflexivity and ethical rigor, and constraints on funding and time. These challenges are illustrated with examples from fieldwork in India and Africa. We recommend a basic approach to case studies aimed at expanding the scope of inquiries into human–wildlife relations beyond studies of rational behavior and quantification of costs and benefits of wildlife to humans.  相似文献   
989.
'Greenhouse gases', especially carbon dioxide, are intimately connected to climate change. To understand the future evolution of the climate system and find ways to manage the concentration of atmospheric carbon dioxide, the processes and feedbacks that drive the carbon cycle must first be understood. However, our current knowledge of spatial and temporal patterns is uncertain, particularly over land and in regions of potentially high sensitivity to change like the boreal zone. The European Space Agency (ESA) GLOBCARBON project aims to generate fully calibrated estimates of at-land products quasi-independent of the original Earth Observation source for use primarily in Dynamic Global Vegetation Models, but also as a contribution to the Global Carbon Project, a cooperation between the International Geosphere Biosphere Programme, International Human Dimensions Programme and the World Climate Research Programme to aid understanding of global carbon cycling. The service will feature estimation of global burned area, the fraction of absorbed photosynthetically active radiation (fAPAR), leaf area index (LAI) and Vegetation Growth Cycle. The demonstrator will focus on ten complete years, from 1998 to 2007 when overlap exists between ESA Earth Observation sensors and others that are synergistic. However, the system will be flexible so that it is not dependent on any single satellite sensor and therefore can be retrospectively applied to existing archives and used with future satellite sensors.  相似文献   
990.
Controlled laboratory chlorination of acetaldehyde (ACD) under typical drinking water conditions (pH 6.7, 7.6 and 8.8, and temperature 4 degrees C and 21 degrees C) revealed that the formation of chloral hydrate (CH), the most common halogenated acetaldehyde (HAs), increased with contact time (0-10 days). However, at increased pH and temperature, CH reached maximum levels and subsequently broke down partially to chloroform and other unidentified compounds. After 10 days contact time, a maximum of 63% (molar) of the initial ACD consumed were converted into CH or chloroform (TCM). Various surveys of drinking water systems indicated that ACD is not the only precursor of CH. A suite of aldehydes (including ACD), and chlorinated disinfection by-products (including TCM and CH) were found in most distribution systems. The levels of bromide in source water impacted speciation of HAs. In addition to CH, brominated and other mixed (Cl/Br) acetaldehydes were detected in most samples; the speciation of HAs and THMs followed comparable trends. Similar to chloroform for trihalomethanes, CH contributed from as low as 5% to up to 60% of the total HAs. The bromine incorporation factors (BIF) in THMs and HAs were shown to increase with increasing bromide ion concentrations in the source water. Brominated THMs are more readily formed than their HA analogues; in fact, BIF values for THMs were 2-3 times higher than for the HAs. It was found that HAs may be as high as THMs in some drinking waters. As a result, the determination of the other target HAs, in addition to CH, is necessary for a better assessment of the pool of disinfection by-products in drinking water.  相似文献   
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