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1.
It has become increasingly common to apply ecological risk assessment (ERA) principles to watershed and regional scale environmental management. This article describes the application of watershed ERA principles to the development of a source water protection assessment and a strategic watershed management plan. The primary focus was on the protection of drinking water quality, a concern typically addressed by human health risk assessors. The approach emphasizes adaptations to the problem formulation phase of ERA (defining assessment endpoints, developing conceptual models and an analysis plan) suitable for watershed management planning in a multi-objective, multi-stressor context. Physical, chemical, and biological attributes were selected for primary drinking water quality assessment endpoints, and coupled with additional assessment endpoints relevant to other environmental and social management objectives. Conceptual models helped the planning team to better understand and communicate the multiple natural and human stressors in the watershed and the causal pathways by which they affected drinking water. The article provides an example of the types of adaptations that can make ERA principles suitable for watershed management related to human health goals, and illustrates the efficiency of integrating health and ecological assessments.  相似文献   

2.
区域生态风险评价的关键问题与展望   总被引:10,自引:0,他引:10  
区域生态风险评价具有多风险因子、多风险受体、多评价终点、强调不确定性因素以及空间异质性的特点,它与传统的生态风险评价在风险源、胁迫因子和评价尺度上具有明显区别。尝试建立了一个基于陆地生态系统的区域生态风险评价框架,同时针对目前区域生态风险评价的研究现状,指出不确定性分析、尺度外推难、评价指标不统一、评价标准不统一、风险因子筛选及优先排序、区域内污染物复合、水生过渡到陆生生态系统风险评价、特殊的人为因素等是目前区域生态风险评价存在的关键问题及难点所在,并提出解决这些问题可能所需的工具、手段和理论方法突破。最后指出区域生态风险观测与数据采集加工、区域生态风险指标体系的统一与整合、区域生态风险评价方法论、区域生态风险的空间分布特征与表达以及区域生态风险评价反馈与管理机制5个方面是区域生态风险评价未来的研究重点。  相似文献   

3.
A regional ecological risk assessment was conducted for the Mountain River catchment in Tasmania, Australia. The Relative Risk Model was used in conjunction with geographic information systems interpretations. Stakeholder values were used to develop assessment endpoints, and regional stressors and habitats were identified. The risk hypotheses expressed in the conceptual model were that agriculture and land clearing for rural residential are producing multiple stressors that have potential for contamination of local waterbodies, eutrophication, changes in hydrology, reduction in the habitat of native flora and fauna, reductions in populations of beneficial insects in agricultural production systems, increased weed competition in pastures, and loss of aesthetic value in residential areas. In the risk analysis the catchment was divided into risk regions based on topography and land use. Stressors were ranked on likelihood of occurrence, while habitats were ranked on percentage land area. Risk characterization showed risks to the maintenance of productive primary industries were highest across all risk regions, followed by maintenance of a good residential environment and maintenance of fish populations. Sensitivity analysis was conducted to show the variability in risk outcomes stemming from uncertainty about stressors and habitats. Outcomes from this assessment provide a basis for planning regional environmental monitoring programs.  相似文献   

4.
Several procedures for Ecological Risk Assessment (ERA) have been suggested. The use of these existing procedures often relies on availability of existing data and/or on large resources for acquisition of new ones. This paper presents a three-tiered procedure for retrospective evaluation of risks adapted to limited resources and scarce background information of relevance for risk assessments, such as in developing countries. The tiers require successively more detailed investigations. The approach assures that resources available for site-specific investigations are directed towards well-formulated questions raised during previous stages of the assessment. The first tier, the preliminary assessment, is a qualitative evaluation of existing information on anthropogenic stressors, sources of stressors and expected ecological effects. The second tier is a regional risk assessment; a semi-quantitative evaluation of ecological risks, over large geographical areas, which results in a ranking of sources and stressors having the greatest potential for ecological impact and ranking of subareas inside the study area more likely to be impacted. The final tier is a site-specific and quantitative risk assessment, at a smaller scale and requiring more resources, that incorporates methodologies for establishing causality between exposure to multiple stressors and effects on specific endpoints of ecological and societal relevance.  相似文献   

5.
Ecological indicators can be defined as relatively simple measurements that relay scientific information about complex ecosystems. Such indicators are used to characterize risk in ecological risk assessment (ERA) and to mark progress toward resource management goals. In late 1997, scientists from the U.S. Environmental Protection Agency and from the Chemical Manufacturers Association (CMA) held a workshop to explore opportunities for collaborative research and scientific exchange on the development and application of ecological indicators. Several scientific challenges were identified as they relate to problem formulation, exposure and effects assessment, and risk characterization. Chief among these were a better understanding of multiple stressors (both chemical and non-chemical), characterization of reference sites and natural variability, extrapolation of measures to ecologically relevant scales, development of comprehensive, ecosystem-based models that incorporate multiple stressors and receptors, and a consistent system for evaluating ecological indicators.  相似文献   

6.
Assessment of risk to public health or environmental resources requires competent characterization of stressors and corresponding effects. Because of the complexity of most stressor-response relationships, it is impossible to completely characterize all the variables, so a select set of measurements is made to reflect the most critical components. Such measurements, or indicators, are included in monitoring programs to estimate trend, stressor source, or magnitude of effects and lead to thresholds for management action or restoration. Although a wide variety of programs and program objectives exists, there are some common challenges for indicator development, including a strong link to management actions. Indicator measurements used in U.S. Environmental Protection Agency (USEPA) risk assessment activities must stem from collaboration among managers, risk assessors, scientists and stakeholders. The primary objective of the USEPA's Fifth Symposium of the National Health and Ecological Effects Research Laboratory was to improve health and ecological risk assessment through dedicated sessions that maximized interaction and discussion among these groups. Existing measurements were challenged for appropriateness, efficiency and scientific validity. Emerging science was explored for greater understanding, better interpretation, and improved methodology. A secondary objective was to uncover and exploit common indicators and supporting data for human health and ecological models.  相似文献   

7.
In the first part of this paper, we showed how life-cycle impact assessment can be described as an exercise in decision analysis. We developed a structure for how to decide on the relative importance of different environmental stressors. In this second part, we offer criteria for the grouping of stressors into impact categories and for the development of impact indicators. Facts to be included in a characterization method should be selected according to their relevance and combined following established scientific models. Facts should be included only if they are informative, that is, if sufficient and sufficiently certain information is available for all stressors that should be evaluated by this method. Abstract, constructed indicators at the ‘midpoint level’ are better suited to compare similar impacts than indicators reflecting ‘observable environmental endpoints’ if there is a large uncertainty about the effects on observable endpoints. We argue that midpoint modeling should be retained. The additional evidence introduced by endpoint methods should be used to support ‘judgments about facts’ needed to evaluate the importance of different impact categories (or means objectives) in the means-ends objectives network.  相似文献   

8.
生态系统完整性内涵及评价方法研究综述   总被引:16,自引:1,他引:15  
生态系统完整性是资源管理和环境保护中一个重要的概念.它主要反映生态系统在外来干扰下维持自然状态、稳定性和自组织能力的程度.评价生态系统完整性对于保护敏感自然生态系统免受人类干扰的影响有着重要的意义.耗散结构理论表明,外界压力和反映系统自组织能力的生物、物理、化学完整性和生态系统功能等对生态系统的完整性有良好的指示作用.本文综述了水生生态系统和陆地生态系统完整性及其所承受的压力评价指标,并探讨了优先评价指标的筛选及综合评价方法,最后根据存在的一些问题提出今后的研究展望.  相似文献   

9.
The U.S. Environmental Protection Agency determined that one of the major impediments to the advancement and application of ecological risk assessment is doubt concerning appropriate assessment endpoints. The Agency's Risk Assessment Forum determined that the best solution to this problem was to define a set of generic ecological assessment endpoints (GEAEs). They are assessment endpoints that are applicable to a wide range of ecological risk assessments; because they reflect the programmatic goals of the Agency, they are applicable to a wide array of environmental issues, and they may be estimated using existing assessment tools. They are not specifically defined for individual cases; some ad hoc elaboration by users is expected. The GEAEs are not exhaustive or mandatory. Although most of the Agency's ecological decisions have been based on organism-level effects, GEAEs are also defined for populations, ecosystems, and special places.  相似文献   

10.
River monitoring and assessment programs are important tools to quantify the condition of river ecosystems, identify deficits, and provide preliminary indication of how to improve them. But, they are limited in delivering comparable assessment results across national or transnational borders, aggregating site-specific assessments into broader scale assessments, and supporting river management decisions. We present a multi-criteria decision analysis approach for improving the comparability of ecological assessment methods of different origin and for combining these assessments into a joint procedure. The approach consists of seven consecutive steps. The most central ones concern the hierarchical allocation of ecological assessment endpoints, and the harmonization of the scoring procedure of attributes (ecological indicators or assets) to a common scale from 0 to 1. We demonstrate the approach integrating three programs developed to assess the hydromorphological river condition in Switzerland, Germany, and the USA. In our example, the integrated assessment produces comparable results for the whole range from natural to impacted rivers, while data continuity with original assessments was maintained. Our approach provides a common assessment standard due to the definition of the minimum amount of information required, is flexible regarding measurement and assessment endpoints, and bridges the gap between river quality assessment and management.  相似文献   

11.
This paper considers the statistical analysis of entomological count data from field experiments with genetically modified (GM) plants. Such trials are carried out to assess environmental safety. Potential effects on nontarget organisms (NTOs), as indicators of biodiversity, are investigated. The European Food Safety Authority (EFSA) gives broad guidance on the environmental risk assessment (ERA) of GM plants. Field experiments must contain suitable comparator crops as a benchmark for the assessment of designated endpoints. In this paper, a detailed protocol is proposed to perform data analysis for the purpose of assessing environmental safety. The protocol includes the specification of a list of endpoints and their hierarchical relations, the specification of intended levels of data analysis, and the specification of provisional limits of concern to decide on the need for further investigation. The protocol emphasizes a graphical representation of estimates and confidence intervals for the ratio of mean abundances for the GM plant and its comparator crop. Interpretation relies mainly on equivalence testing in which confidence intervals are compared with the limits of concern. The proposed methodology is illustrated with entomological count data resulting from multiyear, multilocation field trials. A cisgenically modified potato line (with enhanced resistance to late blight disease) was compared to the original conventional potato variety in the Netherlands and Ireland in two successive years (2013, 2014). It is shown that the protocol encompasses alternative schemes for safety assessment resulting from different research questions and/or expert choices. Graphical displays of equivalence testing at several hierarchical levels and their interpretation are presented for one of these schemes. The proposed approaches should be of help in the ERA of GM or other novel plants.  相似文献   

12.
The need for the extensive use of sustainability assessment as a standalone tool to evaluate the environmental, economic and social aspects of an activity be it at project, product, company or region level has resulted in the development of various methods and standards. There are several indicator issues to address each aspect of sustainability and it is not easy for decision makers to understand the result due to the use of multiple indicators. In this regard, the paper aims at the identification and combination of indicators allowing to assess the sustainability which is applicable to a carbon fiber recycling sector. Indicators selection were carried out by performing an extensive literature review on existing publications dealing with the different pillars of sustainability and setting a number of selection criteria to prioritize indicators that are relevant to the sector. For the environmental aspect global warming, acidification and human toxicity seem to be the most relevant. The social-economic aspect can be addressed through considering the resource impact assessment by considering the supply risk due to the geological scarcity of a resource and the potential supply disruption due to geopolitical and other social factors. The finding shows that three indicators have been identified enabling the assessment of the environmental pillar. Then the necessity to use extra resources indicators was shown and justified by the need of providing a shorter timeframe perspective as well as to consider the amount of fiber to be recycled in the future and also to determine the potential benefit provided by the creation of this sector to the resource strategy point of view. This will be made possible by using such method as the criticality assessment that enable the consideration of geological and geopolitical supply risk as well as the characterization of the system dependence to a specific resource.Finally, these results lead to the expression of the need to the development of a novel indicator assessing the criticality of carbon fibers as well as the expression of the necessity for further research on the socio-economic perspectives.  相似文献   

13.
During the past two decades scientists, regulatory agencies and the European Commission have acknowledged pharmaceuticals to be an emerging environmental problem. In parallel, a regulatory framework for environmental risk assessment (ERA) of pharmaceutical products has been developed. Since the regulatory guidelines came into force the German Federal Agency (UBA) has been evaluating ERAs for human and veterinary pharmaceutical products before they are marketed. The results show that approximately 10% of pharmaceutical products are of note regarding their potential environmental risk. For human medicinal products, hormones, antibiotics, analgesics, antidepressants and antineoplastics indicated an environmental risk. For veterinary products, hormones, antibiotics and parasiticides were most often discussed as being environmentally relevant. These results are in good correlation with the results within the open scientific literature of prioritization approaches for pharmaceuticals in the environment. UBA results revealed that prospective approaches, such as ERA of pharmaceuticals, play an important role in minimizing problems caused by pharmaceuticals in the environment. However, the regulatory ERA framework could be improved by (i) inclusion of the environment in the risk–benefit analysis for human pharmaceuticals, (ii) improvement of risk management options, (iii) generation of data on existing pharmaceuticals, and (iv) improving the availability of ERA data. In addition, more general and integrative steps of regulation, legislation and research have been developed and are presented in this article. In order to minimize the quantity of pharmaceuticals in the environment these should aim to (i) improve the existing legislation for pharmaceuticals, (ii) prioritize pharmaceuticals in the environment and (iii) improve the availability and collection of pharmaceutical data.  相似文献   

14.
Problem formulation is the first step in environmental risk assessment (ERA) where policy goals, scope, assessment endpoints, and methodology are distilled to an explicitly stated problem and approach for analysis. The consistency and utility of ERAs for genetically modified (GM) plants can be improved through rigorous problem formulation (PF), producing an analysis plan that describes relevant exposure scenarios and the potential consequences of these scenarios. A properly executed PF assures the relevance of ERA outcomes for decision-making. Adopting a harmonized approach to problem formulation should bring about greater uniformity in the ERA process for GM plants among regulatory regimes globally. This paper is the product of an international expert group convened by the International Life Sciences Institute (ILSI) Research Foundation.  相似文献   

15.
It is sometimes argued that, from an ecological point of view, population-, community-, and ecosystem-level endpoints are more relevant than individual-level endpoints for assessing the risks posed by human activities to the sustainability of natural resources. Yet society values amenities provided by natural resources that are not necessarily evaluated or protected by assessment tools that focus on higher levels of biological organization. For example, human-caused stressors can adversely affect recreational opportunities that are valued by society even in the absence of detectable population-level reductions in biota. If protective measures are not initiated until effects at higher levels of biological organization are apparent, natural resources that are ecologically important or highly valued by the public may not be adequately protected. Thus, environmental decision makers should consider both scientific and societal factors in selecting endpoints for ecological risk assessments. At the same time, it is important to clearly distinguish the role of scientists, which is to evaluate ecological effects, from the role of policy makers, which is to determine how to address the uncertainty in scientific assessment in making environmental decisions and to judge what effects are adverse based on societal values and policy goals.  相似文献   

16.
A conceptual framework for selecting environmental indicator sets   总被引:1,自引:0,他引:1  
In recent years, environmental indicators have become a vital component of environmental impact assessments and “state of the environment” reporting. This has increased the influence of environmental indicators on environmental management and policy making at all scales of decision making. However, the scientific basis of the selection process of the indicators used in environmental reporting can be significantly improved. In many studies no formal selection criteria are mentioned and when selection criteria are used they are typically applied to indicators individually. Often, no formal criteria are applied regarding an indicator's analytical utility within the total constellation of a selected set of indicators. As a result, the indicator selection process is subject to more or less arbitrary decisions, and reports dealing with a similar subject matter or similar geographical entities may use widely different indicators and consequently paint different pictures of the environment. In this paper, a conceptual framework for environmental indicator selection is proposed that puts the indicator set at the heart of the selection process and not the individual indicators. To achieve this objective, the framework applies the concept of the causal network that focuses on the inter-relation of indicators. The concept of causal networks can facilitate the identification of the most relevant indicators for a specific domain, problem and location, leading to an indicator set that is at once transparent, efficient and powerful in its ability to assess the state of the environment.  相似文献   

17.
生态系统健康评价的研究进展   总被引:82,自引:0,他引:82       下载免费PDF全文
生态系统健康评价是环境管理和生态系统监控的基础,生态系统监控可促进生态系统健康评价。首先介绍了生态系统健康概念的产生,发展及其不同的内涵,并着重回顾和讨论了生态系统健康评价指标及其存在的问题,生态系统健康评价指标包括生态指标,物理化学指标,人类健康与社会经济指标3大类,生态指标是反映生态系统特征和状态的生物指标,它分为生态系统,群落和种群与个体等不同层次的指标或指标体系,物理化学指标是检测生态系统的非生物环境的指标。人类健康与社会经济指标着眼于生态系统对人类生存与社会发展的支持作用,采用经济参数和社会发展的环境压力指标等来衡量生态服务的质量与可持续性,根据其敏感程度和功能性,生态系统健康评价指标分为早期预警指标,适宜程度指标和诊断指标3类,一个完整的生态系统评价应包括上述3大类指标或指标体系,但在具体的评价实践中往往因评价目的和对象的不同而有所选择,生态系统健康评价目前有两个亟待解决的问题,如何有效确立评价标准与参照系以及如何正确区分人为压力和自然干扰。  相似文献   

18.
蝴蝶是进行生物多样性监测、评估及生态环境影响评价的重要指示生物.欧洲对蝴蝶的种类组成、种群动态与分布的长期监测已有数十年的历史,先后实施了许多具有国际性影响的长期监测计划.这些计划的目标是评估区域及国家范围的蝴蝶物种丰富度的变化趋势,分析其与栖境和气候变化等环境因素的相关性,为研究、保护和利用蝴蝶资源及预测环境变化提供基础数据,并在蝴蝶受威胁等级的划分、保护措施的制定、生态环境保护与管理等方面发挥了重要作用.本文在总结欧洲蝴蝶监测历史及现状的基础上,着重介绍英国蝴蝶监测计划(The UK Butterfly Monitoring Scheme, UKBMS)、德国及欧盟等重要的蝴蝶监测计划,同时提出了开展我国蝴蝶监测工作的具体建议.  相似文献   

19.
生态风险评价及研究进展   总被引:31,自引:1,他引:30  
生态风险是当前环境管理研究领域中的一个热点问题,其研究着重关注化学、物理和生物的胁迫因子可能对生态系统或其组分的有害影响.生态风险评价对科学制定环境管理决策有着重要的意义.要对生态系统进行有效地管理,必须预测不利生态影响发生的可能性及后果,减小其对于生态系统或某些组分的损害程度.本文对生态风险评价的研究方法、工具以及研究趋势进行了综述,指出了目前生态风险评价中还需要进一步加强的研究领域,认为在当前城市化水平不断提高的情况下要关注城市生态风险,并针对存在的一些问题提出了今后的研究展望.  相似文献   

20.
Goal, Scope and Background Many disciplines, amongst them LCIA, environmental impact and external cost assessments, are often faced with evaluating trade-offs between two or more alternative options in terms of a range of incommensurable indicators. Using process modeling and valuation, these indicators are quantified at mid- or endpoint levels. Recent discussion amongst LCA experts showed that because of the mutually exclusive aspects of uncertainty and relevance, the midpoint/endpoint debate is controversial and difficult to reconcile. This article is aimed at a more quantitative analysis of mid- and endpoint impacts, and the implications of uncertainty for decision-making. Methods The consequences for decision-making of uncertainties of endpoints are analysed quantitatively for the example of ExternE results, by employing statistical hypothesis testing. The Analytic Hierarchy Process (AHP) is then used to demonstrate the use of multi-criteria techniques at midpoint levels. Results and Discussion Statistical hypothesis testing at the endpoint level shows that for the ExternE example, probabilities of mistakenly favouring one alternative over another when they are in reality indistinguishable can be as high as 80%. Therefore, the best estimate of external cost is inadequate for most policy making purposes. Indicators at midpoint levels are more certain, but since they are only \proxy attributes\, they carry a hidden uncertainty in their relevance. Conclusion If endpoint information is too uncertain to allow a decision to be made with reasonable confidence, then the assessment can be carried out in midpoint terms. However, midpoint indicators are generally further removed from people's experience, and less relevant to the question that people actually want to solve. Nevertheless, if this ultimate question is unanswerable (within the certainty required by the decision-maker), a decision can be made on the basis of stakeholders' subjective judgments about the more certain midpoint levels. The crucial point is that these judgments are able to intuitively incorporate many aspects that impact modeling and valuation has trouble quantifying, such as perceived risk, distribution of burdens and benefits, equity, ethical, moral, religious and political beliefs and principles, immediacy and reversibility of potential impacts, voluntariness, controllability and familiarity of exposure, or perceived incompleteness of human knowledge.  相似文献   

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