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551.
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   
552.
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   
553.
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   
554.
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   
555.
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   
556.
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   
557.
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   
558.
Offshore drilling for oil and gas has been conducted since the early 1900s. Oil and gas under the seabed continue to be an important part of the energy resources of the United States. The need to balance the value of these resources against the potential for environmental damage is an important concern. This article explains why and how the Minerals Management Service (MMS) of the US Department of the Interior uses research in physical sciences to help fulfill its environmental goals, and it provides background information on the role of physical sciences in decision-making for Outer Continental Shelf (OCS) oil, gas, and other minerals development. Established in the 1970s, the MMS Environmental Studies Program is a highly focused marine research program designed to provide the environmental information necessary for OCS energy and nonenergy minerals planning and development activities. The physical sciences research supported by MMS includes physical oceanography, oil-spill risk analyses, atmospheric sciences, and sand and gravel studies. Instead of giving a comprehensive review on physical sciences research in MMS, this article presents sample MMS studies and illustrates how these studies are utilized to support decision-making in environmental management.Published online Note: This version was published online in June 2005 with the cover date of August 2004.  相似文献   
559.
Experimental trials were undertaken over four years to assess the impact of recreational trampling in undisturbed alpine and sub-alpine vegetation communities in the Western Arthur Range, western Tasmania. Data on 'pad' formation due to human trampling were collected using vegetation cover assessments, biomass estimates and detailed cross-sectional surface profiles. In sub-alpine buttongrass and alpine herbfield, prolonged and sustained damage may occur after 100 passes by walkers. The environmental threshold of the flat alpine herbfield site was breached after 200 passes. Plant morphology was one determinant of resistance and resilience, with upright woody shrubs and tall tussock graminoids most vulnerable to sustained trampling damage. Cushions are susceptible to trampling impacts at 500 passes. Loss of vegetation cover peaks 6-12 months after trampling. Our results show that pads formed with as few as 30-100 passes per annum and tracks form at between 100 and 500 passes per annum. Two years after the cessation of trampling, there is some small recovery in vegetation cover after 30 and 100 passes per annum applied for three years, but no evidence of recovery at the 500 pass treatments. The low trampling threshold and slow recovery rates in western Tasmania suggest that concentrating walkers on a minimal number of sites may be the best management option for these untracked alpine and sub-alpine environments.  相似文献   
560.
Predicting mass rapid transit noise levels on an elevated station   总被引:4,自引:0,他引:4  
This study developed a noise prediction model for elevated mass rapid transit (MRT) platforms. Relevant physical and operational parameters (e.g. cruise speed, acceleration and deceleration rates for trains, building fa?ade setbacks and so on) were collected from the Bangkok mass transit system (BTS), the first elevated MRT system operated in Bangkok, Thailand. The equivalent continuous sound pressure levels (L(Aeq)) were collected from both sides of the MRT stations at the center of each platform. The relevant parameters were collected on both platforms and ground level, on both sides of MRT stations. These parameters were statistically tested to determine their correlation with MRT noise. The final model was built from highly correlated parameters using multiple regression analysis with a stepwise regression technique. Statistical evaluation showed a high degree of goodness-of-fit test for the model to the observed data. Therefore, it can be efficiently used for the projection of MRT noise in the affected areas.  相似文献   
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