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591.
本文通过对我国的环境管理发展历程分析后认为,我国的环境管理模式已由过去单一的管理模式转变为强化执法监督、加大投入、注重技术相互结合的综合型管理模式,在继续强化执法监督的同时,不断提高环保投入的比例和不断增加科技含量,是环境管理发展的趋势。  相似文献   
592.
中国环保事业的回顾与展望   总被引:3,自引:0,他引:3  
1970年至现在的30年,中国的环境保护事业大致经历了三个阶段:1970年至1978年,是中国环境保护的萌芽和起步阶段;1979年至1991年,是中国环境保护的奠基和成长阶段;1992年至现在,是中国环境保护的发展和壮大阶段。本文对中国环保事业的发展历程进行了回顾和论述,在此基础上,展望了环境保护的前景,抒发了梦想与期待。  相似文献   
593.
海岸带环境资源综合管理,是对海岸带资源可持续开发利用模式下的现代综合管理。本文在对区域海岸带环境资源综合管理的内涵及管理目标进行分析的基础上,以秦皇岛海岸带环境资源实施综合管理为例,提出了区域海岸带环境资源综合管理的评价过程及模式。  相似文献   
594.
ABSTRACT

Neighborhood life expectancy varies by as much as 10 years across the City of Louisville. In 2013, the Greater Louisville Project funded by local government, businesses, and foundations, argued these differences had little to do with environmental factors. The Greater Louisville Project (2013) study argued that these neighborhood differences could be attributed 40% to socio-economic factors (with a major emphasis on education), 10% to physical environment, 30% to health behaviors, and 20% to access to medical care. To test these claims, we construct our own model of neighborhood variation in years of potential life lost (YPLL) by adding two variables testing environmental degradation. We operationalise two separate measures of environmental contamination: proximity to EPA designated brownfield sites and proximity to chemical factories in an industrial park in the neighborhood known as “Rubbertown”. We conduct several regression analyses, which show a relationship between proximity to environmental contaminants and an increase in neighborhood YPLL. Our beta weights challenge the claims made by the Greater Louisville Project, which minimize the impact nearness to environmental contaminants has on reductions in life expectancy in Louisville neighborhoods.  相似文献   
595.
GOAL, SCOPE AND BACKGROUND: This paper uses two case studies of U.S. Department of Energy nuclear weapons complex installations to illustrate the integration of expedited site characterization (ESC) and multimedia modeling in the remedial action decision making process. CONCEPTUAL SITE MODELS, MULTIMEDIA MODELS, AND EXPEDITED SITE CHARACTERIZATION: Conceptual site models outline assumptions about contaminates and the spatial/temporal distribution of potential receptors. Multimedia models simulate contaminant transport and fate through multiple environmental media, estimate potential human exposure via specific exposure pathways, and estimate the risk of cancer and non-cancer health outcomes. ESC relies on using monitoring data to quantify the key components of an initial conceptual site model that is modified iteratively using the multimedia model. CASE STUDIES: Two case studies are presented that used the ESC approach: Los Alamos National Laboratory (LANL) and Pantex. LANL released radionuclides, metals, and organic compounds, into canyons surrounding the facility. The Pantex Plant has past waste management operations which included burning chemical wastes in unlined pits, burying wastes in unlined landfills, and discharging plant wastewaters into on-site surface waters. CONCLUSIONS: The case studies indicate that using multimedia models with the ESC approach can inform assessors about what, where, and how much site characterization data needs to be collected to reduce the uncertainty associated with risk assessment. Lowering the degree of uncertainty reduces the time and cost associated with assessing potential risk and increases the confidence that decision makers have in the assessments performed.  相似文献   
596.
As part of the first environmental assessment within Montevideo Harbour, in summer and winter of 1998, sediments samples were collected at eight locations to determine the spatial distribution of anthropogenic pollutants. Muddy sediments with high organic matter content dominate the study area. Heavy metal levels indicated that sediments were highly polluted with Zn (overall mean: 312+/-102 microg g(-1) dry sediment), Pb (85+/-31), Cu (89+/-25), Cr (162+/-62), and Hg (0.63+/-0.3) and moderately with Ni (30+/-2) and Ag (1.2+/-0.4). Depending on location and season, aliphatic hydrocarbons reached from 21 to 120 microg g(-1), while the unresolved complex mixture represented up to 76% of the total aliphatic fraction. Total PAH concentrations ranged from 1.56 to 90.44 microg g(-1); except at one location, petroleum derivatives were identified as main local source. The results pointed out that almost all the harbour area presented some substances that can cause adverse biological effects, especially in the inner region where all metals are above PEL levels. Principal components analysis confirmed that the inner harbour region is most severely affected by the pollutants and it was possible to differentiate three regions according to their environmental quality.  相似文献   
597.
The Ethiopian rift is characterized by a chain of lakes of various sizes and hydrological and hydrogeological settings. The rift lakes and feeder rivers are used for irrigation, soda extraction, commercial fish farming, and recreation, and they support a wide variety of endemic birds and wild animals. The levels of some of these lakes have changed dramatically over the last three decades. Lakes that are relatively uninfluenced by human activities (Langano and Abaya) remain stable except for the usual inter-annual variations, strongly influenced by rainfall. Some lakes have shrunk due to excessive abstraction of water; others have expanded due to increases in surface runoff and groundwater flux from percolated irrigation water. Lakes Abiyata and Beseka, both heavily impacted by human activities, show contrasting lake level trends: the level of Abiayata has dropped by about 5 m over three decades because of the extraction of water for soda and an upstream diversion for irrigation. Beseka has expanded from an area of 2.5 to 40 km2 over the last three decades because of increased groundwater inputs from percolated irrigation water. Lake Awassa has risen slightly due to land use changes resulting in increased runoff in its catchment. This paper addresses these lake level changes and their environmental repercussions, based on evidence from hydrometeorological records, hydrogeological field mapping supported by aerial photography and satellite imagery interpretations, water balance estimation, and hydrological modeling. A converging evidence approach is used to reconstruct the temporal and spatial variations of lake levels. The results reveal that the major changes in the rift valley are mainly related to anthropogenic factors. These changes appear to have grave environmental consequences for the fragile rift ecosystem. These consequences demand the very urgent implementation of integrated basin wide water management practice.  相似文献   
598.
In Sweden, environmental policy is essentially carried out through a system of environmental objectives adopted by Parliament in the late 1990s. This system contains principles, objectives, interim targets, strategies, and follow-up mechanisms, which together provide a solid ground for increased efficiency and improved prioritization in environmental policies. Despite the ambitious approach of the Swedish Parliament, the system of environmental objectives suffers from certain shortcomings. Some of the objectives are imprecise and difficult to evaluate, and there are no rules or principles that may be used to solve goal conflicts and to prioritize between different objectives. As a consequence, the environmental objectives tend to differ in their degrees of operationalizability, and the priority-setting between different objectives is often unclear.*Rskr. denotes a written communication (from the Swedish Parliament to the Swedish Government) of a Parliamentary decision. Note: This version was published online in June 2005 with the cover date of August 2004.  相似文献   
599.
The Platte River Basin consists of tributaries largely in Wyoming, Colorado and Western Nebraska, with the main stem in Central Nebraska. Critical wildlife habitat on the main stem requires additional in-stream flows. The watershed is one hosting multiple resources, a variety of users, and managed by an array of state and federal agencies. This study proposes a basis for securing in-stream flows for the Platte River. Candidate water supply mechanisms are suggested based on the way in which Casper, Wyoming secured water for its municipal needs. Canal lining is compared to a dam project, increasing reservoir storage, and purchasing water rights, with consideration also made for water pricing to reduce municipal use. Comparisons are based on economic efficiency, potential water conservation, and property rights criteria. Canal lining, coupled with demand management, is shown to conserve water best, given the set of efficiency and cost criteria for in-stream flow enhancement. The approach offers an opportunity to organize the water supply choice context in a transboundary watershed when quantitative information is limited.  相似文献   
600.
Formulation of effective sustainability indicators for national assessment demands a comprehensive understanding of the utilisation, diffusion and dissemination of information in policy processes. To illustrate the dynamic of sustainability assessment within the context of policy processes, this paper uses a case study of national sustainability indicators development in Malaysia. Subsequently, this paper ascribes the limited achievement of national sustainability assessment in Malaysia to four types of constraints: meta-policy issues; technical capacities; communication concerns; and the inherent knowledge gaps within the indicator developer community vis-a-vis their theoretical limitations. It is proposed that such constraints will be encountered in many countries. Drawing from the literature on public policy, this paper outlines a framework for investigating indicator behaviour within policy processes based on well-established concepts such as knowledge utilisation and policy learning. I conclude this paper by elaborating on the corresponding future challenges that must be addressed before effective integration of sustainability indicators within policy systems can occur.  相似文献   
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