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171.
Within the United Nations Framework Convention on Climate Change (UNFCCC) Kyoto Protocol, countries have significant latitude to define a forest. The most important parameter affecting area designated as forest is the minimum crown cover which can be set between 10 and 30%. The choice will have implications for the amount of land available in a country for afforestation and reforestation activities within the Clean Development Mechanism (CDM-AR). In this paper, we present an analysis of the regional differences in land availability for CDM-AR projects. We then examine how the choice of a high or low threshold value for crown cover will affect the area available for CDM activities and how the limitations imposed by this element of the definition compares to other factors that are likely to limit CDM activities. Results represent a global analysis that included all countries not included in Annex I of the Kyoto Protocol, and examined the effect on land availability of a range of crown cover thresholds ranging from 10–30%. Of the 140 Non-Annex One countries, 107 countries were found to have a potential for CDM-AR projects. Asia had the largest amount of combined area suitable for CDM-AR at the 10% crown cover threshold level. However, at 30%, South America had the greatest amount of land available, and a large change in available land area, which increased by almost five times compared to what was available at the 10% threshold. The area available in Africa increased by a factor of 5.5. Central America showed the largest increase, to almost 10 times more at the 30% threshold. By contrast, within Asia, the area increase was comparatively less, but still the area nearly doubled. Globally, a low threshold of 10% crown cover excluded almost 2/3 of the land identified that was eligible at 30%, over 5 million km2. The spatial analyses showed not only the effects of the choice of the crown cover criterion, but also where the land was available for CDM activities within each country at different thresholds. Protected areas account for 10–20% of the CDM-AR eligible area in most countries.  相似文献   
172.
Environmental Science and Pollution Research - The large-scale use of quaternary ammonium compounds (QACs) in medicines or disinfectants can lead to their release into the environment, posing a...  相似文献   
173.
174.
The paper focuses on the example of a local island community in Greece, to illustrate the difficulties of effective consensus building, in support of sustainable policies. In the first section the issue of sustainability and the importance of participation are discussed, before moving to a brief outline of the nature of participation and its sources since the 1960s. It follows an analysis of the epistemological framework of consensus building process which is considered as the most integrated and sophisticated version of participatory planning. This analysis serves as a background for judging the appropriateness of consensus building for the resolution of an environmental problem harassing a Greek island community. It is about the problem of water availability and management in the small Aegean island of Leros. The paper shows how illegal practices in the use of water, administrative fragmentation and confusion over knowledge of the problem and its solutions lead to divisions in the stakeholder groups and to obstacles in the way of participation. The intrinsic problems embedded in Greek (and probably not alone) society and political culture, which prevent collective action and participation, account in part for the anticipated risk of unwelcome, illegitimate outcomes of a potential consensus building process. Nevertheless, if communicative planning is to gain universal acceptance, it should first resolve some critical theoretical and practical shortcomings related to its normative, ethical and philosophical assumptions. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
175.
The relationship between exposure to the World Trade Center (WTC) attacks, increased substance use, functional impairment and mental health service use, controlling for depression and post-traumatic stress disorder, was assessed through an in-school survey of directly exposed students (N = 1040) attending the five middle and five high schools nearest the WTC. The survey was conducted 18 months after the attacks. Students with one WTC exposure risk factor had a five-fold increase in substance use, while those with three or more exposure risks had a nearly 19-fold increase. Increased substance use was associated with impaired school work, school behaviour and grades. Students reporting increased substance use were nearly twice as likely to want help but were no more likely than asymptomatic students to receive services. Adolescents reporting increased substance use, without co-morbidity, were less likely to receive psychological services than others. Attention to the needs of substance-using adolescents exposed to disaster is needed.  相似文献   
176.
Environmental Science and Pollution Research - Enterolert-E is an easy-to-use method for the enumeration of enterococci in water samples as an indicator of fecal pollution. This most probable...  相似文献   
177.
Hybridization between endangered species and more common species is a significant problem in conservation biology because it may result in extinction or loss of adaptation. The historical reduction in abundance and geographic distribution of the American plains bison (Bison bison bison) and their recovery over the last 125 years is well documented. However, introgression from domestic cattle (Bos taurus) into the few remaining bison populations that existed in the late 1800s has now been identified in many modern bison herds. We examined the phenotypic effect of this ancestry by comparing weight and height of bison with cattle or bison mitochondrial DNA (mtDNA) from Santa Catalina Island, California (U.S.A.), a nutritionally stressful environment for bison, and of a group of age‐matched feedlot bison males in Montana, a nutritionally rich environment. The environmental and nutritional differences between these 2 bison populations were very different and demonstrated the phenotypic effect of domestic cattle mtDNA in bison over a broad range of conditions. For example, the average weight of feedlot males that were 2 years of age was 2.54 times greater than that of males from Santa Catalina Island. In both environments, bison with cattle mtDNA had lower weight compared with bison with bison mtDNA, and on Santa Catalina Island, the height of bison with cattle mtDNA was lower than the height of bison with bison mtDNA. These data support the hypothesis that body size is smaller and height is lower in bison with domestic cattle mtDNA and that genomic integrity is important for the conservation of the American plains bison. Efectos Fenotípicos del ADN Mitocondrial de Ganado en el Bisonte Americano  相似文献   
178.
Fires in agricultural ecosystems emit greenhouse gases and aerosols that influence climate on multiple spatial and temporal scales. Annex 1 countries of the United Nations Framework Convention on Climate Change (UNFCCC), many of which ratified the Kyoto Protocol, are required to report emissions of CH4 and N2O from these fires annually. In this study, we evaluated several aspects of this reporting system, including the optimality of the crops targeted by the UNFCCC globally and within Annex 1 countries, and the consistency of emissions inventories among different countries. We also evaluated the success of individual countries in capturing interannual variability and long-term trends in agricultural fire activity. In our approach, we combined global high-resolution maps of crop harvest area and production, derived from satellite maps and ground-based census data, with Terra and Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) measurements of active fires. At a global scale, we found that adding ground nuts (e.g., peanuts), cocoa, cotton and oil palm, and removing potato, oats, rye, and pulse other from the list of 14 crops targeted by the UNFCCC increased the percentage of active fires covered by the reporting system by 9%. Optimization led to a different recommended list for Annex 1 countries, requiring the addition of sunflower, cotton, rapeseed, and alfalfa and the removal of beans, sugarcane, pulse others, and tuber-root others. Extending emissions reporting to all Annex 1 countries (from the current set of 19 countries) would increase the efficacy of the reporting system from 6% to 15%, and further including several non-Annex 1 countries (Argentina, Brazil, China, India, Indonesia, Thailand, Kazakhstan, Mexico, and Nigeria) would capture over 55% of active fires in croplands worldwide. Analyses of interannual trends from the United States and Australia showed the importance of both intensity of fire use and crop production in controlling year-to-year variations in agricultural fire emissions. Remote sensing provides an effective means for evaluating some aspects of the current UNFCCC emissions reporting system; and, if combined with census data, field experiments and expert opinion, has the potential to improve the robustness of the next generation inventory system.  相似文献   
179.
To effectively manage large natural reserves, resource managers must prepare for future contingencies while balancing the often conflicting priorities of different stakeholders. To deal with these issues, managers routinely employ models to project the response of ecosystems to different scenarios that represent alternative management plans or environmental forecasts. Scenario analysis is often used to rank such alternatives to aid the decision making process. However, model projections are subject to uncertainty in assumptions about model structure, parameter values, environmental inputs, and subcomponent interactions. We introduce an approach for testing the robustness of model-based management decisions to the uncertainty inherent in complex ecological models and their inputs. We use relative assessment to quantify the relative impacts of uncertainty on scenario ranking. To illustrate our approach we consider uncertainty in parameter values and uncertainty in input data, with specific examples drawn from the Florida Everglades restoration project. Our examples focus on two alternative 30-year hydrologic management plans that were ranked according to their overall impacts on wildlife habitat potential. We tested the assumption that varying the parameter settings and inputs of habitat index models does not change the rank order of the hydrologic plans. We compared the average projected index of habitat potential for four endemic species and two wading-bird guilds to rank the plans, accounting for variations in parameter settings and water level inputs associated with hypothetical future climates. Indices of habitat potential were based on projections from spatially explicit models that are closely tied to hydrology. For the American alligator, the rank order of the hydrologic plans was unaffected by substantial variation in model parameters. By contrast, simulated major shifts in water levels led to reversals in the ranks of the hydrologic plans in 24.1-30.6% of the projections for the wading bird guilds and several individual species. By exposing the differential effects of uncertainty, relative assessment can help resource managers assess the robustness of scenario choice in model-based policy decisions.  相似文献   
180.
The Atlantic blue crab Callinectes sapidus is an important fisheries resource that is subject to mortality and morbidity from hemolymph infections. We used culture-independent methods based on the analysis of 16S rRNA genes to characterize and quantify the microflora from the carapace, gut, and hemolymph of C. sapidus with the goals of (1) characterizing the C. sapidus microbial assemblage and (2) identifying the reservoirs of potential pathogens associated with the crab. We found that the carapace, gut and hemolymph microflora have a core Proteobacteria community with contributions from other phyla including Bacteroidetes, Firmicutes, Spirochetes, and Tenericutes. Within this Proteobacteria core, γ-Proteobacteria, including the members of the Vibrionaceae that are closely related to potential pathogens, dominate. Bacteria closely related to hemolymph pathogens were found on the carapace, supporting the hypothesis that punctures, molting damage, or broken dactyls may be routes for hemolymph infections. These results provide some of the first data on the blue crab microbial assemblage obtained with culture-independent techniques and offer insights into the routes of infection and potential bacterial pathogens associated with blue crabs.  相似文献   
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