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411.
志愿非法规性举措(VNRI)在加拿大的使用,加之审慎混用各种手段,包括法规框架与经济手段,已经带来公司文化和行为的显著变化.随着各家公司和代表其利益的协会鼓励环境领导,负责任企业家便成为一种现实.详细考察了两个计划:加速削减/消除毒物(ARET)和全国包装议定书(NaPP).虽然这两个计划在其目的、目标和对象上有显著差异,而且它们所解决的环境问题也不同,但两者都成功地加以实施,达到了以低于法规所设想的费用达到最高环境质量水平之目的,并产生了更大的和未预见到的效益.  相似文献   
412.

Greenhouse gas (GHG) inventories at national or provincial levels include the total emissions as well as the emissions for many categories of human activity, but there is a need for spatially explicit GHG emission inventories. Hence, the aim of this research was to outline a methodology for producing a high-resolution spatially explicit emission inventory, demonstrated for Poland. GHG emission sources were classified into point, line, and area types and then combined to calculate the total emissions. We created vector maps of all sources for all categories of economic activity covered by the IPCC guidelines, using official information about companies, the administrative maps, Corine Land Cover, and other available data. We created the algorithms for the disaggregation of these data to the level of elementary objects such as emission sources. The algorithms used depend on the categories of economic activity under investigation. We calculated the emissions of carbon, nitrogen sulfure and other GHG compounds (e.g., CO2, CH4, N2O, SO2, NMVOC) as well as total emissions in the CO2-equivalent. Gridded data were only created in the final stage to present the summarized emissions of very diverse sources from all categories. In our approach, information on the administrative assignment of corresponding emission sources is retained, which makes it possible to aggregate the final results to different administrative levels including municipalities, which is not possible using a traditional gridded emission approach. We demonstrate that any grid size can be chosen to match the aim of the spatial inventory, but not less than 100 m in this example, which corresponds to the coarsest resolution of the input datasets. We then considered the uncertainties in the statistical data, the calorific values, and the emission factors, with symmetric and asymmetric (lognormal) distributions. Using the Monte Carlo method, uncertainties, expressed using 95% confidence intervals, were estimated for high point-type emission sources, the provinces, and the subsectors. Such an approach is flexible, provided the data are available, and can be applied to other countries.

  相似文献   
413.
目前,全球的经济和社会发展已进入资源和环境的瓶颈.然而,由于全世界都在使用的污泥量计算方法存在错误,酿成包括我国在内的各国政府在决策中出现重大失误,造成污染失控.本文试图给出正确算式,说明处理污泥要尊重自然法则,建立蝇虫转化、微生物还原的生物链,使用系统生物工程技术无害化处理、资源化利用.  相似文献   
414.
We measured an array of biophysical and spectral variables to evaluate the response and recovery of Spartina alterniflora to a sudden dieback event in spring and summer 2004 within a low marsh in coastal Virginia, USA. S. alterniflora is a foundation species, whose loss decreases ecosystem services and potentiates ecosystem state change. Long-term records of the potential environmental drivers of dieback such as precipitation and tidal inundation did not evidence any particular anomalies, although Hurricane Isabel in fall 2003 may have been related to dieback. Transects were established across the interface between the dieback area and apparently healthy areas of marsh. Plant condition was classified based on ground cover within transects as dieback, intermediate and healthy. Numerous characteristics of S. alterniflora culms within each condition class were assessed including biomass, morphology and spectral attributes associated with photosynthetic pigments. Plants demonstrated evidence of stress in 2004 and 2005 beyond areas of obvious dieback and resilience at a multi-year scale. Resilience of the plants was evident in recovery of ground cover and biomass largely within 3 y, although a small remnant of dieback persisted for 8 y. Culms surviving within the dieback and areas of intermediate impact had modified morphological traits and spectral response that reflected stress. These morphometric and spectral differences among plant cover condition classes serve as guidelines for monitoring of dieback initiation, effects and subsequent recovery. Although a number of environmental and biotic parameters were assessed relative to causation, the reason for this particular dieback remains largely unknown, however.  相似文献   
415.
The Benguela Current Large Marine Ecosystem off southwest Africa is a regionally valued system because of its biological productivity, which supports high biomass throughout the foodweb, and a rich diversity of habitats and species. However, the region is exposed to numerous anthropogenic pressures that are likely to escalate under future economic growth. In response, the Benguela Current Commission called for a spatial biodiversity assessment (BCC-SBA) to identify conservation priorities, including potential areas for marine protected areas. The systematic conservation-planning approach to this assessment requires a fine-scale map of coastal habitats, which was not previously available for the region. Our aim was to undertake this mapping, within tight logistic and resource limitations. We used a previously derived methodology for mapping the distribution of coastal habitats from aerial imagery. The Benguela coast is approximately 5,047 km long. Half of this extent is sandy beach, a third is rocky and mixed shores, 13 % comprises lagoonal features, and the remainder (4 %) comprises estuaries and offshore islands. The distribution and extent of these coastal habitats differs substantially alongshore (i.e. with latitude), with conditions ranging north–south from hot, humid mangrove-lined lagoons, to hyper-arid coastal desert sandy beaches. Patterns in regional geology, climate and oceanography are proposed as the main drivers of spatial heterogeneity in coastal habitat types. The resulting ecological and socio-economic wealth requires proactive protection (supported through the BCC-SBA, for example), to ensure sustainable utilization of the rich natural resources, and persistence of these resources for the benefit of current and future generations.  相似文献   
416.
Multiple paternity and offspring quality in tree swallows   总被引:1,自引:0,他引:1  
There is mounting evidence in a variety of taxa that females increase offspring quality by mating with multiple males, often resulting in multiple paternity. In birds, however, few studies have explicitly examined the benefits of mating with several different males; instead, the focus has been on whether or not extra-pair mating occurs, and its adaptive significance remains controversial. We examined the hypothesis that offspring quality, particularly immune response (phytohaemagglutinin assay) and growth, increases with the number of sires in broods of socially monogamous tree swallows (Tachycineta bicolor). We found one of the highest known levels of multiple paternity in birds (84% of nests with two or more extra-pair young had at least two extra-pair sires). Among nests with extra-pair young, the number and diversity of sires continued to increase linearly with the number of extra-pair young, so there was no evidence that some males monopolized paternity at high levels of extra-pair fertilization. Indeed, the number of sires was actually greater than expected in large broods, suggesting that some females might be seeking more mates. We found no effect of the number of sires on nestling immune response or growth. In mixed paternity broods, the immune response of extra-pair young did not differ from that of their within-pair half-siblings. However, among all broods, nestlings had a stronger immune response in nests with at least one extra-pair nestling than in nests with all within-pair nestlings. These results are not consistent with a good genes benefit of extra-pair mating, but they do suggest that there are environmental effects associated with extra-pair mating that increase nestling immune response. These environmental effects could produce indirect genetic effects on sexual selection if they are heritable. The extraordinarily high number of sires in this species highlights a relatively unexplored source of sexual selection in birds.  相似文献   
417.
Official response to explosive volcano hazards usually involves evacuation of local inhabitants to safe shelters. Enforcement is often difficult and problems can be exacerbated when major eruptions do not ensue. Families are deprived of livelihoods and pressure to return to hazardous areas builds. Concomitantly, prevailing socio-economic and political conditions limit activities and can influence vulnerability. This paper addresses these issues, examining an ongoing volcano hazard (Tungurahua) in Ecuador where contextual realities significantly constrain responses. Fieldwork involved interviewing government officials, selecting focus groups and conducting surveys of evacuees in four locations: a temporary shelter, a permanent resettlement, with returnees and with a control group. Differences in perceptions of risk and health conditions, and in the potential for economic recovery were found among groups with different evacuation experiences. The long-term goal is to develop a model of community resilience in long-term stress environments.  相似文献   
418.
The U.S. Environmental Protection Agency helped select in situ vitrification (ISV) as an interim response action for the National Priority List (NPL) site at the Rocky Mountain Arsenal (RMA) in Commerce City, Colorado. That decision is being reviewed, pending redesign of the technology by its vendor for what would be the largest ISV project in the United States, involving 220 tons of arsenic, twenty-six tons of mercury, and low levels of organic compounds. That material was left in three arsenic precipitation basins that were used from 1942 to 1947 to manufacture chemical warfare agents and later backfilled. This article explores the eight principal environmental, technical, and financial factors that EPA's Region VII must address before committing $1,200 per cubic yard, or $14 million, to seal that material in glass.  相似文献   
419.
The common approach to performing quantitative risk assessments in the contaminated land industry in the UK lacks a formal methodology for the treatment of the full range of uncertainties and for documenting decisions regarding the development of conceptual models and the selection of computer codes. The approach presented here represents an alternative, more detailed, and systematic approach for developing conceptual models and addressing uncertainties when undertaking contaminated land risk assessments. It is intended that the advantages of this approach are recognised by practitioners in the contaminated land industry and adopted, where appropriate, to help improve the quality of contaminated land risk assessments. The identification of features, events, and processes (FEPs) has been applied to safety assessments of deep geological and near-surface disposal of radioactive wastes. One of the primary benefits of using this approach is in the development of conceptual models. The approach identifies the FEPs that need to be addressed during the development of conceptual models and in the selection of suitable computer codes that can be used to represent the conceptual models. This approach has been applied by BNFL at the low-level radioactive waste disposal site at Drigg in Cumbria and is currently being adopted for a contaminated land study at the Sellafield site, also in Cumbria. This paper presents the advantages of using FEPs in the development of conceptual models and the treatment of uncertainties. The paper also discusses the application of this approach to contaminated land studies and provides an example to demonstrate the application of the approach. BNFL's approach at the Drigg site involves the identification of components (features) and phenomena (events and processes) that govern interactions and dependencies between the components by arranging them in a matrix format.  相似文献   
420.
This article reviews the state of the science regarding the health effects of polybrominated dibenzo-p-dioxins (PBDDs) and dibenzofurans (PBDFs). While thousands of articles have been published on the health effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin and related polychlorinated dibenzodioxins (PCDDs) and dibenzofurans (PCDFs), little is know about the brominated and mixed chloro/bromo homologs. Available literature suggests that brominated compounds have similar toxicity profiles to their chlorinated homologs. However, further research investigating health effects will only be useful if exposure scenarios truly exist. Current exposure data is extremely limited, posing a major data gap in assessing potential risk of these chemicals. The rapid increase in the use of brominated flame retardants has raised the level of environmental concern regarding PBDDs/PBDFs as it is likely that human, as well as wildlife, exposure to brominated dioxins and furans will increase with their use.  相似文献   
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