Self-Organizing Maps for Integrated Environmental Assessment of the Mid-Atlantic Region

A new method has been developed to perform environmental assessment at regional scale. This involves a combination of a self-organizing map (SOM) neural network and principal component analysis (PCA). The method is capable of clustering ecosystems in terms of environmental conditions and suggesting relative cumulative environmental impacts of multiple factors across a large region. Using data on land-cover, population, roads, streams, air pollution, and topography of the Mid-Atlantic region, the method was able to indicate areas that are in relatively poor environmental condition or vulnerable to future deterioration. Combining the strengths of SOM with those of PCA, the method offers an easy and useful way to perform a regional environmental assessment. Compared with traditional clustering and ranking approaches, the described method has considerable advantages, such as providing a valuable means for visualizing complex multidimensional environmental data at multiple scales and offering a single assessment or ranking needed for a regional environmental assessment while still facilitating the opportunity for more detailed analyses.     

Sensitivity Analysis of Aggregated Indices for Integrated Assessment with a Case Study of the Mid-Atlantic Region

Environmental indicators are often aggregated into a single index for various purposes in environmental studies. Aggregated indices derived from the same data set can differ, usually because the aggregated indices' sensitivities are not thoroughly analyzed. Furthermore, if a sensitivity analysis is carried out, it is not presented in a transparent fashion to policy decision-makers. This paper presents a method of generating various aggregated environmental indices and analyzing their sensitivities via the use of the fuzzy set concept. Results show that several insights into the environmental conditions of the study area (e.g., the distribution of good or bad values of indicators at a watershed and or across the region) can be revealed in the sensitivity analysis of aggregated indices.     

Environmental Integrated Assessment via Monte Carlo Simulation with a Case Study of the Mid-Atlantic Region,USA

Environmental integrated assessments are often carried out via the aggregation of a set of environmental indicators. Aggregated indices derived from the same data set can differ substantially depending upon how the indicators are weighted and aggregated, which is often a subjective matter. This article presents a method of generating aggregated environmental indices in an objective manner via Monte Carlo simulation. Rankings derived from the aggregated indices within and between three Monte Carlo simulations were used to evaluate the overall environmental condition of the study area. Other insights, such as the distribution of good or bad values of indicators at a watershed and/or a subregion, were observed in the study.     

Groundwater Vulnerability Assessment for Organic Compounds: Fuzzy Multicriteria Approach for Mexico City

This study was based on a groundwater vulnerability assessment approach implemented for the Mexico City Metropolitan Area (MCMA). The approach is based on a fuzzy multicriteria procedure integrated in a geographic information system. The approach combined the potential contaminant sources with the permeability of geological materials. Initially, contaminant sources were ranked by experts through the Analytic Hierarchy Process. An aggregated contaminant sources map layer was obtained through the simple additive weighting method, using a scalar multiplication of criteria weights and binary maps showing the location of each source. A permeability map layer was obtained through the reclassification of a geology map using the respective hydraulic conductivity values, followed by a linear normalization of these values against a compatible scale. A fuzzy logic procedure was then applied to transform and combine the two map layers, resulting in a groundwater vulnerability map layer of five classes: very low, low, moderate, high, and very high. Results provided a more coherent assessment of the policy-making priorities considered when discussing the vulnerability of groundwater to organic compounds. The very high and high vulnerability areas covered a relatively small area (71 km² or 1.5% of the total study area), allowing the identification of the more critical locations. The advantage of a fuzzy logic procedure is that it enables the best possible use to be made of the information available regarding groundwater vulnerability in the MCMA.     

论综合型休闲娱乐场所环境影响评价的工作重点

娱乐及餐饮业近年来发展迅速,开展这类项目的环境影响评价工作首先应确保其环保审批手续的前置性。环评单位应在项目筹划初期介入,工作中应以项目合理选址和提出具有可操作性的污染防治措施这两个侧重面开展工作,作出准确的评价结论,给出可行的污染防治措施及方案。只有这样,才能编制出较为完善的环境影响评价文件,才能达到预防或减轻不良环境影响的最终目的。     

A Hierarchical Fuzzy Decision Support System for the Environmental Rehabilitation of Lake Koronia,Greece

This article presents the design of a fuzzy decision support system (DSS) for the assessment of alternative strategies proposed for the restoration of Lake Koronia, Greece. Fuzzy estimates for the critical characteristics of the possible strategies, such as feasibility, environmental impact, implementation time, and costs are evaluated and supplied to the fuzzy DSS. Different weighting factors are assigned to the critical characteristics and the proposed strategies are ordered with respect to the system responses. The best strategies are selected and their expected impact on the ecosystem is evaluated with the aid of a fuzzy model of the lake. Sensitivity analysis and simulation results have shown that the proposed fuzzy DSS can serve as a valuable tool for the selection and evaluation of appropriate management actions. Note: This version was published online in June 2005 with the cover date of August 2004.     

The Arctic Water Resource Vulnerability Index: An Integrated Assessment Tool for Community Resilience and Vulnerability with Respect to Freshwater

People in the Arctic face uncertainty in their daily lives as they contend with environmental changes at a range of scales from local to global. Freshwater is a critical resource to people, and although water resource indicators have been developed that operate from regional to global scales and for midlatitude to equatorial environments, no appropriate index exists for assessing the vulnerability of Arctic communities to changing water resources at the local scale. The Arctic Water Resource Vulnerability Index (AWRVI) is proposed as a tool that Arctic communities can use to assess their relative vulnerability-resilience to changes in their water resources from a variety of biophysical and socioeconomic processes. The AWRVI is based on a social-ecological systems perspective that includes physical and social indicators of change and is demonstrated in three case study communities/watersheds in Alaska. These results highlight the value of communities engaging in the process of using the AWRVI and the diagnostic capability of examining the suite of constituent physical and social scores rather than the total AWRVI score alone.     

Environmental Condition Assessment of US Military Installations Using GIS Based Spatial Multi-Criteria Decision Analysis

Environment functions in various aspects including soil and water conservation, biodiversity and habitats, and landscape aesthetics. Comprehensive assessment of environmental condition is thus a great challenge. The issues include how to assess individual environmental components such as landscape aesthetics and integrate them into an indicator that can comprehensively quantify environmental condition. In this study, a geographic information systems based spatial multi-criteria decision analysis was used to integrate environmental variables and create the indicator. This approach was applied to Fort Riley Military installation in which land condition and its dynamics due to military training activities were assessed. The indicator was derived by integrating soil erosion, water quality, landscape fragmentation, landscape aesthetics, and noise based on the weights from the experts by assessing and ranking the environmental variables in terms of their importance. The results showed that landscape level indicator well quantified the overall environmental condition and its dynamics, while the indicator at level of patch that is defined as a homogeneous area that is different from its surroundings detailed the spatiotemporal variability of environmental condition. The environmental condition was mostly determined by soil erosion, then landscape fragmentation, water quality, landscape aesthetics, and noise. Overall, environmental condition at both landscape and patch levels greatly varied depending on the degree of ground and canopy disturbance and their spatial patterns due to military training activities and being related to slope. It was also determined the environment itself could be recovered quickly once military training was halt or reduced. Thus, this study provided an effective tool for the army land managers to monitor environmental dynamics and plan military training activities. Its limitation lies at that the obtained values of the indicator vary and are subjective to the experts' knowledge and experience. Thus, further advancing this approach is needed by developing a scientific method to derive the weights of environmental variables.     

模糊数学在矿山环境影响评价中的应用

环境质量是一个涉及多因素多层级的模糊概念,用经典数学进行环境质量评价,评判环境质量的等级只能用一个绝对判据来划分,无法处理模糊因素边界不清晰、中间过渡不分明的问题。本文应用模糊数学方法,在单环境因素模糊综合评价的基础上,进行了总体环境质量模糊综合评价的探讨,结合某区域环境实例,对其总体环境质量进行了模糊综合评价,并将评价结果与用经典数学评价结果进行了比较,比较表明,环境质量模糊评价方法较经典数学评价方法更客观更准确。     

环境质量评价模糊集理论与模式研究

探讨了模糊集理论方法对环境质量评价的可行性，以大气环境质量评价为例，叙述了这种方法的研究程序及计算步骤。研究表明，采用模糊集理论方法对大气环境质量进行评价，结果结果合理，方法可行，有一定的参考价值。     

基于模糊数学的大气环境质量综合评价

鉴于大气环境质量评价中客观存在的不确定性和模糊性,运用模糊数学方法,选用SO2、NO2、PM10作为评价因子,参照大气环境质量标准,通过计算污染因子权重分配系数和隶属度对乌鲁木齐市2004年至2010年大气环境质量给出客观的评价,综合评价结果表明乌鲁木齐市总体大气环境质量为轻度污染(三级),但空气质量在逐年好转,SO2和PM10依然是乌鲁木齐市空气质量的制约因子,且NO2的权重在逐年上升。模糊综合评判考虑环境空气质量评价的模糊性,根据污染物浓度对各级别的贴近度考察污染物的级别,评价结果比较直观,可以细致准确的评价环境质量等级,评价结果基本可以反映环境空气污染的情况。     

Groundwater Vulnerability Assessment Using Fuzzy Logic: A Case Study in the Zayandehrood Aquifers, Iran

Groundwater is an important source of water, especially in arid and semi-arid regions where surface water is scarce. Groundwater pollution in these regions is consequently a major concern, especially as pollution control and removal in these resources are not only expensive but at times impossible. It is, therefore, essential to prevent their contamination in the first place by properly identifying vulnerable zones. One method most commonly used for evaluating groundwater pollution is the DRASTIC method, in which the Boolean logic is used to rank and classify the parameters involved. Problems arise, however, in the application of the Boolean logic. In this paper, the fuzzy logic has been used to avoid the problems. For this purpose, three critical cases of minimum, maximum, and mean values have been considered for the net recharge parameter. The process has been performed on the Zayandehrood river basin aquifers. The fuzzy-DRASTIC vulnerability map thus obtained indicates that the western areas of the basin generally have the maximum pollution potential followed by the areas located in the east. The central parts of the study area are found to have a low pollution potential. Finally, two sensitivity analyses are performed to show the significance of each value of the net recharge parameter in the calculation of vulnerability index.     

Quantitative Assessment of the Intertidal Environment of Kuwait I: Integrated Environmental Classification

Quantitative analysis of physical, chemical and biological data of the intertidal zone in Kuwait was undertaken to develop an integrated basis for assessing and protecting this sensitive coastal ecosystem. Cluster analyses were performed to determine the resemblance between the sampling stations based on the sediment composition, the benthic macrofauna and the physico-chemical characteristics of the intertidal sediment/water. Five distinct sub-environments were delineated within the intertidal zone of Kuwait. Each sub-environment was described in terms of number of taxa, mean density of organisms, sediment type, tidal level and dominant organisms. The physico-chemical parameters investigated were found to be unimportant in the distribution of the intertidal benthic macrofauna. On the other hand, sediment type was found to be a major factor in the overall composition of the benthic community. The benthic fauna and related characteristics of the sub-environments could be used as indicators to monitor changes in the intertidal ecosystem and as guides to protection and management of the different coasts. The approach described in this paper could also be adopted elsewhere to provide a sound basis for evaluating environmental impacts and for developing sustainable coastal management.     

环境影响评价中生物多样性的影响评价探析

环境影响评价分为规划环境影响评价和建设项目环境影响评价。由于两种环境评价类型的发展情况不同,其生物多样性影响评价的发展情况也有所不同。根据其特点概括分析了生物多样性影响评价的现状,包括评价原则和评价方法,指出不足之处,并初步提出了评价指标的筛选。     

Environmental Vulnerability Indicators for Environmental Planning and Decision-Making: Guidelines and Applications

Environmental decision-making and policy-making at all levels refers necessarily to synthetic, approximate quantification of environmental properties such as vulnerability, conservation status, and ability to recover after perturbation. Knowledge of such properties is essential to informed decision-making, but their definition is controversial and their precise characterization requires investments in research, modeling, and data collection that are only possible in the most developed countries. Environmental agencies and governments worldwide have increasingly requested numerical quantification or semiquantitative ranking of such attributes at the ecosystem, landscape, and country level. We do not have a theory to guide their calculation, in general or specific contexts, particularly with the amount of resources usually available in such cases. As a result, these measures are often calculated with little scientific justification and high subjectivity, and such doubtful approximations are used for critical decision-making. This problem applies particularly to countries with weak economies, such as small island states, where the most precious environmental resources are often concentrated. This paper discusses frameworks for a “least disappointing,” approximate quantification of environmental vulnerability. After a review of recent research and recent attempts to quantify environmental vulnerability, we discuss models and theoretical frameworks for obtaining an approximate, standardizable vulnerability indicator of minimal subjectivity and maximum generality. We also discuss issues of empirical testing and comparability between indicators developed for different environments. To assess the state of the art, we describe an independent ongoing project developed in the South Pacific area and aimed to the comparative evaluation of the vulnerability of arbitrary countries.     

环境质量模糊综合评价及其应用

环境质量评价是环境科学的重要研究课题之一，作者评述了常用指标法的不足，提出用模糊数学中综合模糊评价法评价环境质量，建立了评价模式和计算程序，并用于科学城的环境质量评价，评价计算给出的多层次数据所提供的信息，与监测结果所体现的环境质量状况符合，所建模糊评价程序是适用的。     

Discretionary Judgement in Local Planning Authority Decision Making: Screening Development Proposals for Environmental Impact Assessment

Screening is a critical decision-stage in the Environmental Impact Assessment (EIA) process and involves the determination of whether or not a development proposal will require EIA. This decision requires a discretionary judgement on whether the development has the potential to cause ‘significant environmental effects’, and consequently there is potential for diversity to exist in formal requests for EIA. Drawing upon a comprehensive survey of Local Planning Authorities (LPAs) in England and Wales, this paper explores the characteristics of LPA screening decision making since the introduction of revised EIA regulations in March 1999. The paper starts with a theoretical overview of rationality, decision making and planning theory, followed by a brief review of the regulatory context of EIA screening. The research approach is then outlined and the survey findings are presented, including a detailed consideration of organizational and individual level analyses set within the context of planning theory judgement debates. Comparisons with other European countries are briefly made, before drawing conclusions and recommendations.     

填埋场环境影响评价决策支持系统的研究和开发

通过分析我国填埋场环评存在的问题，本文提出采用VB6．0的方法，基于知识推理来建立填埋环境影响评价决策支持系统（LEIADSS），使填埋场环评工作标准化。实例研究显示，利用VB6．0编程语言可以方便的完成该系统的设计，且能使环评工作快速、准确的完成。