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141.
太湖沉积物重金属污染及生态风险性评价 总被引:26,自引:6,他引:20
对1993年~1999年所采集的太湖表层沉积物中重金属含量进行了统计分析和生态风险性评价.结果表明,太湖沉积物的pH值呈中性至弱碱性,较适合于沉积物中粘土矿物及腐殖质对重金属的吸附;太湖大部分地区沉积物未受到重金属污染,且沉积物中重金属处于安全状态.沉积物生态风险性指数评价结果也表明,太湖大部分地区目前无重金属生态危害. 相似文献
142.
根据昆明政府颁布的《昆明市松华坝水源保护区生产生活补助办法(试行)》要求,在系统探讨了松华坝水源保护区实施补助的重要性和必要性的基础上,分析了办法实行可能产生的效果,并针对性地提出实施建议。 相似文献
143.
After introducing soft defence techniques as an alternative to hard defence techniques, the need is emphasized to consider
the coastal area as an integral system. By recalling the main driving factors for coastal management: conflict resolution,
resilience and sustainability, we logically arrive at the concepts of ecological engineering and ecotechnology, which are
increasingly acknowledged as possible solutions to achieve sustainable use of coastal space as a resource. In this context,
we refer to the principles of self design and of ecosystem conservation.
In order to deal with real situations we are in need of fundamental ‘tools’ for the application of the soft intervention technology
approach. We therefore introduce the concept of physiographic units and develop an initial elaboration for a coastal stretch
and for coastal wetlands. The latter deserve more attention because of the already established practices of ecotechnology,
at least as far as water and soil quality are concerned, but certainly also concerning morphology, especially in the future.
We conclude by briefly discussing how activities undertaken in two research projects currently being conducted under the framework
of the Marine Science and Technology Program of the Commission of the European Communities are expected to contribute to the
concepts introduced here. 相似文献
144.
In view of no generally accepted ecological compensation standards and methods at present,this paper discusses the introduction of the negotiation system to the process of ecological compensation for water source areas.That is,the government in water source areas and the downstream regions of river basins should confirm their respective rights and obligations and then establish their compensation standards through negotiations according to the different purposes of water use.The amount of compensation should be determined in the comprehensive consideration of the quality,quantity and compensation price of water.Through open and fair negotiations,an institutional arrangement will be set up,which can make the water source areas and the downstream regions of river basins fully express their true preferences and their independent choices on the ecological environment. 相似文献
145.
Jukka Lehto Jussi Paatero Reijo Pehrman Seija Kulmala Juhani Suksi Teija Koivula Timo Jaakkola 《Journal of environmental radioactivity》2008,99(10):1656
Lichen–soil column samples were taken from several locations in the Southern Finland between 1986 and 2006. Columns were divided into three parts, upper lichen, lower lichen and underlying soil, and their gamma emitting radionuclides, 134Cs, 137Cs, 103Ru, 95Zr, 106Ru, 110mAg, 125Sb and 144Ce, were measured with gamma spectrometry. Deposition values were calculated as Bq/m2 for each sampling site. Distribution of various radionuclides in the three compartments as a function of time was determined. Both effective and ecological half-lives of all radionuclides were calculated for upper lichen, whole lichen and whole lichen–soil column. A linear relation was derived between the physical half-lives and effective half-lives for whole lichen and for whole lichen–soil column. Reindeer meat activity concentrations of various radionuclides and ensuing radiation doses to reindeer-herding people were also estimated for a hypothetical case where a similar high radioactive pollution, as was taken place in the Southern Finland, would have occurred in the reindeer-herding areas in the Finnish Lapland. 相似文献
146.
Qinhua Fang Luoping Zhang Huasheng Hong Liyu Zhang Frances Bristow 《Environment, Development and Sustainability》2008,10(1):41-49
Environmental planning at different levels has been called for by environmental departments in China during last years to
integrate environment consideration to economic development. Based on the accomplished environmental planning practice in
Xiamen China, the paper suggests a general environmental planning process with ecological function zoning as its key steps,
at the same time an effective method for ecological function zoning was formulated. The case studies of Dongfu suburban town
environmental planning and Xiamen eco-city conceptual planning indicate that scientifically sound results of ecological function
zoning can contribute to improving not only the adaptability and acceptability of environmental planning, also the environmental
management and the decision-making. The experience shows that the ecological function zoning methods should be applied according
to the principles of adaptive management, resource-based and community-based, so that it can integrate science into decision-making
process, avoiding both narrow-minded viewpoints of planners and natural resource use conflicts among variety of stakeholders.
Problems to be resolved in the future are also pointed out in the ending part. 相似文献
147.
环境损害赔偿之关键前提:因果关系判定 总被引:2,自引:0,他引:2
近年来,随着经济的快速发展,我国环境污染事故频繁发生,随之引发的环境损害问题越发严重。然而由于技术的局限性,大多数损害得不到赔偿。因果关系判定,作为环境损害赔偿的关键前提,正是我国面对环境污染事故频发而亟待解决的问题。本文首先基于环境损害的因果链条,以科学严谨的角度,构建了一套适合我国且具有可操作性的环境损害因果关系判定程序;而后,为了避免由于环境系统的复杂性而导致该程序无法顺利进行的情况发生,本文对国外先进的因果关系判定原则进行了分析,并以此建立了判定程序和判定原则相结合的因果关系判定体系,该体系旨在帮助遇到"瓶颈"的判定程序能够按照体系中的判定原则以一种"迂回"的方式继续进行。本文所构建因果关系判定体系,在保证科学严谨性的同时,兼顾了实用性和时效性,避免了因果关系判定这一关键环节陷入无休止的考证和证明之中,对环境损害赔偿体系的建立具有重要的理论意义与技术支持作用。 相似文献
148.
Rethinking receiver operating characteristic analysis applications in ecological niche modeling 总被引:2,自引:0,他引:2
The area under the curve (AUC) of the receiver operating characteristic (ROC) has become a dominant tool in evaluating the accuracy of models predicting distributions of species. ROC has the advantage of being threshold-independent, and as such does not require decisions regarding thresholds of what constitutes a prediction of presence versus a prediction of absence. However, we show that, comparing two ROCs, using the AUC systematically undervalues models that do not provide predictions across the entire spectrum of proportional areas in the study area. Current ROC approaches in ecological niche modeling applications are also inappropriate because the two error components are weighted equally. We recommend a modification of ROC that remedies these problems, using partial-area ROC approaches to provide a firmer foundation for evaluation of predictions from ecological niche models. A worked example demonstrates that models that are evaluated favorably by traditional ROC AUCs are not necessarily the best when niche modeling considerations are incorporated into the design of the test. 相似文献
149.
150.
A multiple criteria evaluation of sustainable agricultural development models using AHP 总被引:2,自引:0,他引:2
Selection of the appropriate agricultural development model has become an important issue in Iran. Using data from Fars province
of Iran, the purpose of this paper is to use analytic hierarchy process (AHP) for selecting between the two competing sustainable
agricultural development models, which have been developed based on the general tenets of Ecological Modernization (EM) and
De-Modernization (DM) theories. Farmers, environmentalists, board members of rural cooperative, rural women and experts from
Fars Agricultural (Jehad-e-Keshavarzi) Organization participated in application of AHP to this study. They applied AHP to
determine the priority of DM and EM based sustainable agricultural development models. Each group determined the priority
of the two models for sustainable agricultural development. The findings indicated that ecological criteria i.e. wise use
of resources, environmental protection and product quality are the most important criteria for sustainable agriculture of
Iran, followed by economic criterion employment and social criterion participation. A sensitivity analysis was carried out
to determine the critical factors that affected the priority of alternatives. The results indicated that EM-based sustainable
agricultural development model has a higher priority as the theoretical base of agricultural development of Iran.
Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue 相似文献