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Currently popular concepts such as sustainable development and sustainability seek the integration of environment and development planning. However, there is little evidence that this integration is occurring in either mainstream development planning or environmental planning. This is a function of the history, philosophies, and evolved roles of both. A brief review of the experience and results of mainstream planning, environmental planning, and ecosystem science suggests there is much in past scientific and professional practice that is relevant to the goal of integrated planning for environment and development, but still such commonly recommended reforms as systems and multidisciplinary approaches, institutional integration, and participatory, goal-oriented processes are rarely achieved. “Ecosystem approaches,” as developed and applied in ecology, human ecology, environmental planning, anthropology, psychology, and other disciplines, may provide a more transdisciplinary route to successful integration of environment and development. Experience with ecosystem approaches is reviewed, their advantages and disadvantages are discussed, and they are compared to traditional urban and regional planning, environmental planning, and ecosystem science approaches. Ultimately a synthesis of desirable characteristics for a framework to integrate environment and development planning is presented as a guide for future work and a criterion for evaluating existing programs.  相似文献   
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Climate change is altering nutrient cycling within the Arctic Ocean, having knock-on effects to Arctic ecosystems. Primary production in the Arctic is principally nitrogen-limited, particularly in the western Pacific-dominated regions where denitrification exacerbates nitrogen loss. The nutrient status of the eastern Eurasian Arctic remains under debate. In the Barents Sea, primary production has increased by 88% since 1998. To support this rapid increase in productivity, either the standing stock of nutrients has been depleted, or the external nutrient supply has increased. Atlantic water inflow, enhanced mixing, benthic nitrogen cycling, and land–ocean interaction have the potential to alter the nutrient supply through addition, dilution or removal. Here we use new datasets from the Changing Arctic Ocean program alongside historical datasets to assess how nitrate and phosphate concentrations may be changing in response to these processes. We highlight how nutrient dynamics may continue to change, why this is important for regional and international policy-making and suggest relevant research priorities for the future.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01673-0.  相似文献   
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Assessments of risk to biodiversity often rely on spatial distributions of species and ecosystems. Range‐size metrics used extensively in these assessments, such as area of occupancy (AOO), are sensitive to measurement scale, prompting proposals to measure them at finer scales or at different scales based on the shape of the distribution or ecological characteristics of the biota. Despite its dominant role in red‐list assessments for decades, appropriate spatial scales of AOO for predicting risks of species’ extinction or ecosystem collapse remain untested and contentious. There are no quantitative evaluations of the scale‐sensitivity of AOO as a predictor of risks, the relationship between optimal AOO scale and threat scale, or the effect of grid uncertainty. We used stochastic simulation models to explore risks to ecosystems and species with clustered, dispersed, and linear distribution patterns subject to regimes of threat events with different frequency and spatial extent. Area of occupancy was an accurate predictor of risk (0.81<|r|<0.98) and performed optimally when measured with grid cells 0.1–1.0 times the largest plausible area threatened by an event. Contrary to previous assertions, estimates of AOO at these relatively coarse scales were better predictors of risk than finer‐scale estimates of AOO (e.g., when measurement cells are <1% of the area of the largest threat). The optimal scale depended on the spatial scales of threats more than the shape or size of biotic distributions. Although we found appreciable potential for grid‐measurement errors, current IUCN guidelines for estimating AOO neutralize geometric uncertainty and incorporate effective scaling procedures for assessing risks posed by landscape‐scale threats to species and ecosystems.  相似文献   
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江湾自然绿地的生态现状调查   总被引:2,自引:0,他引:2  
在2001年考察的基础上,2002年2月和5月,对江湾机场旧址次生性生态系统的现状与发展趋势进行了较全面的调研,调查发现,目前该区域有高等植物31科61种、土壤动物30种,鸟类43种,特别是湿地景观得到了较好的发育,同时,该区域的部分地段存在环境污染严重,多种破坏环境的人类活动以及外来物种入侵等问题,鉴于该区域地处上海市区,具有较高的环境,社会以及经济价值,对上海生态城市的建设具有重要的影响,建议在职能部门确定发展规划之前,采取有效措施予以管理。  相似文献   
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本文计对三峡库区紫色丘陵地区的土壤生态环境状况,提出了优化评价的总目标、评价指标体系和评价程序,探讨了单项指数评价方法的数学模型与基准参数,在此基础上,应用了层次分析与模糊数学的原理和方法,对紫色土生态优化进行综合评价,旨在为库区及库周生态与环境建设及经济综合开发提供依据。  相似文献   
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Harvesting in an eight-species ecosystem   总被引:2,自引:0,他引:2  
The theory for a general equilibrium ecosystem model that can include large number of interacting species is presented. Features include: (1) individual plants and animals are assumed to behave as if they are maximizing their net energy intake, (2) short- and long-run equilibriums are obtained, (3) species’ population adjustments depend on individual net energies. The theory is applied using simulations of an eight-species Alaskan marine ecosystem for which a “natural” equilibrium is calculated. Humans are introduced by adding a regulated open access fishery that harvests one of the species. Fishing impacts the fish population as well as the populations of other species, including Stellar sea lions, an endangered species. The sensitivity of fish and nonfish species populations to harvesting are calculated.  相似文献   
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Ecosystem Impacts of Geoengineering: A Review for Developing a Science Plan   总被引:1,自引:0,他引:1  
Geoengineering methods are intended to reduce climate change, which is already having demonstrable effects on ecosystem structure and functioning in some regions. Two types of geoengineering activities that have been proposed are: carbon dioxide (CO(2)) removal (CDR), which removes CO(2) from the atmosphere, and solar radiation management (SRM, or sunlight reflection methods), which reflects a small percentage of sunlight back into space to offset warming from greenhouse gases (GHGs). Current research suggests that SRM or CDR might diminish the impacts of climate change on ecosystems by reducing changes in temperature and precipitation. However, sudden cessation of SRM would exacerbate the climate effects on ecosystems, and some CDR might interfere with oceanic and terrestrial ecosystem processes. The many risks and uncertainties associated with these new kinds of purposeful perturbations to the Earth system are not well understood and require cautious and comprehensive research.  相似文献   
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The rapid increase in atmospheric concentrations of greenhouse gases has caused concern because of their potential to alter the earth's radiation budget and disrupt current climate patterns While there are many uncertainties associated with use of general circulation models (GCMs), GCMs are currently the best available technology to project changes in climate associated with elevated gas concentrations. Results indicate increases in global temperature and changes in global precipitation patterns are likely as a result of doubled CO2. GCMs are not reliable for use at the regional scale because local scale processes and geography are not taken into account. Comparison of results from five GCMs in three regions of the United States indicate high variability across regions and among models depending on season and climate variable. Statistical methods of scaling model output and nesting finer resolution models in global models are two techniques that may improve projections. Despite the many limitations in GCMs, they are useful tools to explore climate-earth system dynamics when used in conjunction with water resource and ecosystem models. A variety of water resource models showed significant alteration of regional hydrology when run with both GCM-generated and hypothetical climate scenarios, regardless of region or model complexity. Similarly, ecological models demonstrate the sensitivity of ecosystem production, nutrient dynamics, and distribution to changes in climate and CO2 levels. We recommend the use of GCM-based scenarios in conjunction with water resource and ecosystem models to guide environmental management and policy in a “no-regrets” framework or as part of a precautionary approach to natural resource protection.  相似文献   
10.
With the ending of the Cold War, several federal agencies are reclaiming land through remediation and restoration and are considering potential future land uses that are compatible with current uses and local needs. Some sites are sufficiently contaminated that it is likely that the responsible federal agency will retain control over the land for the foreseeable future, providing them with a stewardship mission. This is particularly true of some of the larger Department of Energy (DOE) facilities contaminated during the production of nuclear weapons. The use of the term “restoration” is explored in this paper because the word means different things to the public, ecologists, and environmental managers responsible for contaminated sites, such as Superfund sites and the DOE facilities. While environmental restoration usually refers to remediation and removal of hazardous wastes, ecological restoration refers to the broader process of repairing damaged ecosystems and enhancing their productivity and/or biodiversity. The goals of the two types of restoration can be melded by considering environmental restoration as a special case of ecological restoration, one that involves risk reduction from hazardous wastes, and by broadening environmental restoration to include a more extensive problem-formulation phase (both temporal and spatial), which includes the goal of reestablishing a functioning ecosystem after remediation. Further, evaluating options for the desired post remediation result will inform managers and policy-makers concerning the feasibility and efficacy of environmental restoration itself.  相似文献   
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