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981.
建设项目环境影响因素分析 总被引:2,自引:0,他引:2
从一个建设项目的全生命周期角度出发,对其设计阶段、原材料阶段、现场施工阶段、运行维护阶段和拆除阶段对环境产生的影响进行了分析,并提出了减轻这种不利影响的对策与措施。 相似文献
982.
Cassar Michelle 《Journal of Coastal Conservation》2003,9(1):73-80
This paper examines a 3-yr EU LIFE-funded project for the management of two especially protected areas on the Maltese coast.
Project partners are the Euro-Mediterranean Centre on Insular Coastal Dynamics (ICoD), the Gaia Foundation and the Ministry
for the Environment of Malta.
Project sites are the Ghajn Tuffieha area on the northwest coast of Malta, and the Ramla Bay area on the island of Gozo. While
both sites are in a relatively pristine state and comprise a number of features of ecological and scientific importance, they
are also prime recreational areas, hosting thousands of visitors especially during the summer months. The challenge is to
manage these sites in a sustainable manner in order to protect their unique ecology while simultaneously controlling and managing
the human activities taking place there.
The following sequence of activities is being implemented at both sites: surveys of the resources present (biodiversity, habitats,
geological and hydrological features, and archaeological heritage), implementation of first intervention measures, and the
drawing up and implementation of site-specific management plans, including rehabilitation and protection of biodiversity and
habitats, regulations for site use, and awareness raising and educational measures.
The management structure of this project supports the concept of decentralization of management of protected areas, through
the granting of responsibility for the direct management of these sites to a non-governmental organization, under joint government/EU
funding. This paper thus presents the project as a model for similar initiatives for the management of protected sites in
the Mediterranean. 相似文献
983.
984.
Objectives for Multiple-Species Conservation Planning 总被引:2,自引:0,他引:2
Abstract: The first step in conservation planning is to identify objectives. Most stated objectives for conservation, such as to maximize biodiversity outcomes, are too vague to be useful within a decision-making framework. One way to clarify the issue is to define objectives in terms of the risk of extinction for multiple species. Although the assessment of extinction risk for single species is common, few researchers have formulated an objective function that combines the extinction risks of multiple species. We sought to translate the broad goal of maximizing the viability of species into explicit objectives for use in a decision-theoretic approach to conservation planning. We formulated several objective functions based on extinction risk across many species and illustrated the differences between these objectives with simple examples. Each objective function was the mathematical representation of an approach to conservation and emphasized different levels of threat. Our objectives included minimizing the joint probability of one or more extinctions, minimizing the expected number of extinctions, and minimizing the increase in risk of extinction from the best-case scenario. With objective functions based on joint probabilities of extinction across species, any correlations in extinction probabilities had to be known or the resultant decisions were potentially misleading. Additive objectives, such as the expected number of extinctions, did not produce the same anomalies. We demonstrated that the choice of objective function is central to the decision-making process because alternative objective functions can lead to a different ranking of management options. Therefore, decision makers need to think carefully in selecting and defining their conservation goals. 相似文献
985.
化工项目无组织废气评价探讨 总被引:2,自引:0,他引:2
化工项目无组织废气具有排放量小、种类多、排放点广、难以量化等特点.无组织废气的评价是化工项目环评的重要组成部分,评价的主要思路是找出排放源、筛选出主要的排污环节和污染因子、确定排放源强、科学公正地作出评价结论.通过实例说明了做好无组织废气评价在实践环评工作中的重要性. 相似文献
986.
为了从控制运行的角度促进简化数学模型的应用,必须借助其它优化手段进一步提高预测精度。本文主要介绍了应用于简化数学模型的扩展卡尔曼滤波、神经网络和误差反馈系统三种优化方法以及优化后的验证结果。从验证结果来看,优化的ROM模型与ASMl模型的定性变化行为相似,基于神经网络的复合模型对PO4^3-和NOx^-的预测结果非常准确,误差反馈的优化系统模拟性能良好。 相似文献
987.
分析了香港建设项目环境影响评价制度体系的发展、现状及评价程序,总结了香港建设项目环境影响评价制度的特点,为中国内地建设项目环境影响评价制度的完善提出了借鉴依据。 相似文献
988.
主要介绍广州港新沙港区8-10^#泊位集集装箱系统改建工程环境建设情况,论述改建工程如何实施环保“三同时”及实现环境效益,经济效益和社会效益的统一。 相似文献
989.
对环境影响货币化方法的探讨 总被引:1,自引:0,他引:1
在项目环境影响评价中,社会经济评价一直是个难点。为此,提出了通过设想一个“反效果补偿项目”来货币化污染项目对环境的影响,确定项目环境成本的方法,探讨了对环境评价与经济评价标准的统一。 相似文献
990.
The SITES reserve selection system: A critical review 总被引:1,自引:0,他引:1
Douglas?T.?FischerEmail author Richard?L.?Church 《Environmental Modeling and Assessment》2005,10(3):215-228
Numerous models have been put forth to help with the growing demand for the establishment of biodiversity reserves. One site
selection model that has been used in several recent studies is SITES [S.J. Andelman, I. Ball, F.W. Davis and D.M. Stoms,
SITES V 1.0: an analytical toolbox for designing ecoregional conservation portfolios, Unpublished manual prepared for the
nature conservancy, 1999, 1–43. (available at )]. SITES includes two heuristic solvers: based on Greedy and Simulated Annealing. We discuss the formulation of the SITES
model, present a new formulation for that problem, and solve a number of test problems optimally using off-the-shelf software.
We compared our optimal results with the SITES Simulated Annealing heuristic and found that SITES frequently returns significantly
suboptimal solutions. Our results add further support to the argument, started by Underhill [L.G. Underhill, Optimal and suboptimal
reserve selection algorithms, Biol. Conserv. 70 (1994) 85–87], continuing through Rodrigues and Gaston [A.S.L. Rodrigues and
K.J. Gaston, Optimization in reserve selection procedures – why not?, Biol. Conserv. 107 (2002) 123–129], for greater integration
of optimal methods in the reserve design/selection literature. 相似文献