An approach to integrated ecological assessment of resource condition: the Mid-Atlantic estuaries as a case study

The complex and interconnected nature of ecological systems often makes it difficult to understand and prevent multiresource, multistressor problems. This article describes a process to assess ecological condition at regional scales. The article also describes how the approach was applied to the Mid-Atlantic estuaries, where it focused on characterizing the current state of the environment rather than on predicting future effects from humans. The necessity for iteration during the exercise showed how important it was to identify the purpose of the assessment and its users, that appropriate, consistent data are lacking for large-scale assessments, and that it remains a challenge to communicate succinctly the results of such an assessment.     

Using Wildlife as Receptor Species: A Landscape Approach to Ecological Risk Assessment

To assist risk assessors at the Department of Energy’s Savannah River Site (SRS), a Geographic Information System (GIS) application was developed to provide relevant information about specific receptor species of resident wildlife that can be used for ecological risk assessment. Information was obtained from an extensive literature review of publications and reports on vertebrate- and contaminant-related research since 1954 and linked to a GIS. Although this GIS is a useful tool for risk assessors because the data quality is high, it does not describe the species’ site-wide spatial distribution or life history, which may be crucial when developing a risk assessment. Specific receptor species on the SRS were modeled to provide an estimate of an overall distribution (probability of being in an area). Each model is a stand-alone tool consisting of algorithms independent of the GIS data layers to which it is applied and therefore is dynamic and will respond to changes such as habitat disturbances and natural succession. This paper describes this modeling process and demonstrates how these resource selection models can then be used to produce spatially explicit exposure estimates. This approach is a template for other large federal facilities to establish a framework for site-specific risk assessments that use wildlife species as endpoints.Current address: Biology Department, University of South Dakota, Vermillion, SD 57069     

Applying Ecological Risk Principles to Watershed Assessment and Management

Considerable progress in addressing point source (end of pipe) pollution problems has been made, but it is now recognized that further substantial environmental improvements depend on controlling nonpoint source pollution. A watershed approach is being used more frequently to address these problems because traditional regulatory approaches do not focus on nonpoint sources. The watershed approach is organized around the guiding principles of partnerships, geographic focus, and management based on sound science and data. This helps to focus efforts on the highest priority problems within hydrologically-defined geographic areas. Ecological risk assessment is a process to collect, organize, analyze, and present scientific information to improve decision making. The U.S. Environmental Protection Agency (EPA) sponsored three watershed assessments and found that integrating the watershed approach with ecological risk assessment increases the use of environmental monitoring and assessment data in decision making. This paper describes the basics of the watershed approach, the ecological risk assessment process, and how these two frameworks can be integrated. The three major principles of watershed ecological risk assessment found to be most useful for increasing the use of science in decision making are (1) using assessment endpoints and conceptual models, (2) holding regular interactions between scientists and managers, and (3) developing a focus for multiple stressor analysis. Examples are provided illustrating how these principles were implemented in these assessments.     

How to evaluate raw material supply risks—an overview

Some strategic raw materials do have an extremely unsecure supply situation. Several working groups around the world have made criticality assessments for metallic raw materials to analyze the driving impact factors for this instability. However, the influences on raw material availability are manifold and therefore criticality assessment methods are very heterogeneous. Here we give an overview about the differences and similarities of supply risk evaluation in 15 criticality assessment methods. We take the example of Indium, which has been rated in 60% of these criticality studies, and show which data base is used for supply risk evaluation. Our results show a lack of consensus about which indicators give reliable information for raw material supply risk and how these indicators should be aggregated. We anticipate our essay to be a starting point for more justified indicator selection and weighting in criticality assessments.     

Assessing ecological risk on a regional scale

Society needs a quantitative and systematic way to estimate and compare the impacts of environmental problems that affect large geographic areas. This paper presents an approach for regional risk assessment that combines regional assessment methods and landscape ecology theory with an existing framework for ecological risk assessment. Risk assessment evaluates the effects of an environmental change on a valued natural resource and interprets the significance of those effects in light of the uncertainties identified in each component of the assessment process. Unique and important issues for regional risk assessment are emphasized; these include the definition of the disturbance scenario, the assessment boundary definition, and the spatial heterogeneity of the landscape. Although the research described in this article has been funded wholly or in part by the United States Environmental Protection Agency (EPA) through Interagency Agreement Number DW89932112-01-2 to the U.S. Department of Energy, it has not been subjected to EPA review and therefore does not necessarily reflect the views of EPA and no official endorsement should be inferred.     

The Use of an Ecologic Classification to Improve Water Resource Planning in New Zealand

The Resource Management Act (RMA) legislates the management of most natural resources in New Zealand. The RMA invokes ecosystem-based management by requiring that regulation be based on managing the effects of resource according to “the life supporting capacity” of the environment. The management of water resources under the RMA is carried out at the regional level by regional councils. Regional councils can develop regional water plans to establish objectives and criteria for water management. Regional water planning under the RMA has been problematic, and regional plan objectives developed under the RMA have been criticized as too broad and not sufficiently quantified. As a consequence, many resource users are unconvinced of the need for the regulatory criteria promulgated by plans, whereas other groups are concerned that the environment is inadequately protected. This article proposes that a lack of ecologically relevant management units has prevented regional water plans from fulfilling their intended function under the RMA. Then it introduces the use of River Environment Classification as a means of defining units for assessment and management, and provides three case studies that demonstrate its potential to support regional water management planning. The discussion shows that the specificity of regional assessments can be increased if ecologic variation is stratified into distinctive units (i.e., units within which variation in the characteristics of interest is reduced) as part of the assessment process. The increased specificity of the assessments increases the possibility that regional objectives and criteria for water management can be derived that are quantitative and justifiable and that provide certainty for stakeholders. The authors conclude that greater choice and meaning can be generated in regional planning processes if regional variation in ecologic characteristics is stratified using a classification, and if classes are used as units for assessment and management.     

A Framework for Assessing Climate Change Impacts on Water and Watershed Systems

In this article we present a framework for assessing climate change impacts on water and watershed systems to support management decision-making. The framework addresses three issues complicating assessments of climate change impacts—linkages across spatial scales, linkages across temporal scales, and linkages across scientific and management disciplines. A major theme underlying the framework is that, due to current limitations in modeling capabilities, assessing and responding to climate change should be approached from the perspective of risk assessment and management rather than as a prediction problem. The framework is based generally on ecological risk assessment and similar approaches. A second theme underlying the framework is the need for close collaboration among climate scientists, scientists interested in assessing impacts, and resource managers and decision makers. A case study illustrating an application of the framework is also presented that provides a specific, practical example of how the framework was used to assess the impacts of climate change on water quality in a mid-Atlantic, U.S., watershed.     

ECOLOGICAL CONSEQUENCE ASSESSMENT: EFFECTS OF BIOENGINEERED ORGANISMS1

ABSTRACT: The introduction of genetically altered microorganisms into natural ecosystems presents fundamentally new problems in risk assessment and ecological effect evaluation. Novel microorganisms, produced by any of several new methods, have the ability to survive and reproduce in the environment. Since most of these organisms are bacteria, they have the potential to interfere with natural processes, displace natural populations, infect new hosts, move between ecosystems, and cause far-reaching ecological disturbanes. This paper reviews currently available methods in ecological research that might be used in evaluating the ecological effects of releasing genetically altered microorganisms. Both structural and functional evaluations are critically reviewed. Microcosm, mesocosm, and field tests should provide valuable predictions concerning the potential ecological impact of genetically altered organisms. Ecosystem assessments will also be useful in post-release studies such as those currently used to evaluate toxic impacts. The present problem does not require the development of new testing methods but rather the creation of adequate predictive models (both conceptual and systems-based) to predict the potential for adverse effect of genetically altered organisms.     

A regional framework for establishing recovery criteria

Effective assessments of aquatic ecosystem recovery require ecologically sound endpoints against which progress can be measured. Site-by-site assessments of end points and potential recovery trajectories are impractical for water resource agencies. Because of the natural variation among ecosystems, applying a single set of criteria nationwide is not appropriate either. This article demonstrates the use of a regional framework for stratifying natural variation and for determining realistic biological criteria. A map of ecoregions, drawn from landscape characteristics, formed the framework for three statewide case studies and three separate studies at the river basin scale. Statewide studies of Arkansas, Ohio, and Oregon, USA, streams demonstrated patterns in fish assemblages corresponding to ecoregions. The river basin study in Oregon revealed a distinct change at the ecoregion boundary; those in Ohio and Montana demonstrated the value of regional reference sites for assessing recovery. Ecoregions can be used to facilitate the application of ecological theory and to set recovery criteria for various regions of states or of the country. Such a framework provides an important alternative between site-specific and national approaches for assessing recovery rates and conditions.     

干旱生态敏感区水电站环境影响后评价指标体系研究

针对干旱生态敏感区水电站环境影响后评价的要求,设计备选指标集,采用频次分析法进行指标初选,采用专家咨询法进行指标精选,建立由4项二级指标、14项三级指标构成的干旱生态敏感区水电站环境影响后评价指标体系,采用层次分析法给每个指标赋予权重。将该评价指标体系用于某水电站建设的实例分析,结果表明,水电站运行以来总体上有利影响大于不利影响,并且在可接受范围内,其不利影响可以采取人工辅助措施加以避免或减缓。评价结果符合实际,该指标体系具有针对性和一定的实用性。     

黄河中上游能源化工区重点产业发展战略生态风险评价

结合黄河中上游能源化工区重点产业发展战略生态风险宏观性、综合性、复杂性的特点,论文以生态风险景观评价方法及3S技术等为研究手段,综合考虑重点产业发展战略人为风险源及自然风险源,以生态风险受体和终点选择、风险源分析、暴露危害分析、生态风险综合评价及生态风险分区为评价步骤,揭示了重点产业发展战略潜在生态风险空间分异特征。研究结果表明：黄河中上游重点产业战略实施区可划分为三类生态风险监控区,生态风险重点监控区自然风险源分布集中,重点产业人为风险源和自然风险源交织在一起,极易发生生态风险放大效应,生态风险次重点监控区自然生态风险源分布较单一,局部重点产业人为风险源强度增强,将增加区域生态风险水平,生态风险监控区自然生态风险源分布范围较小,潜在生态风险水平相对较低。论文探索了战略环评生态风险评价方法和评价思路,为国内重点产业发展战略生态风险评价提供了借鉴。     

土壤污染风险评价研究进展

随着工业化和城镇化快速发展,土壤污染带来的人体健康和生态风险日益凸显.本文针对我国土壤污染环境风险评价体系在风险管控中的缺失问题,系统总结了国内外土壤污染的风险研究发展成果,按照土壤污染的人体健康风险和生态风险,分别进行评价方法、评价标准和管理实践的总结与评述.文章着重指出:土壤污染风险评价在生态系统水平及区域流域尺度上缺失,评价方法未能与污染物存在形态完全匹配,评价指标还不能覆盖大部分重金属和有机物,健康风险与生态风险还没有实现综合评价.     

A conceptual model for assessing ecological risk to water quality function of bottomland hardwood forests

Ecological risk assessment provides a methodology for evaluating the threats to ecosystem function associated with environmental perturbations or stressors. This report documents the development of a conceptual model for assessing the ecological risk to the water quality function (WQF) of bottomland hardwood riparian ecosystems (BHRE) in the Tifton-Vidalia upland (TVU) ecoregion of Georgia. Previus research has demonstrated that mature BHRE are essential to maintaining water quality in this portion of the coastal plain. The WQF of these ecosystems is considered an assessment endpoit—an ecosystem function or set of functions that society chooses to value as evidenced by laws, regulations, or common usage. Stressors operate on ecosystems at risk through an exposure scenario to produce ecological effects that are linked to loss of the desired function or assessment end point. The WQF of BHRE is at risk because of the ecological and environmental quality effects of a suite of chemical, physical, and biological stressors. The stressors are related to nonpoint source pollution from adjacent land uses, especially agriculture; the conversion of BHRE to other land uses; and the encroachment of domestic animals into BHRE. Potential chemical, physical, and biological stressors to BHRE are identified, and the methodology for evaluating appropriate exposure scenarios is discussed. Field-scale and watershed-scale measurement end points of most use in assessing the effects of stressors on the WQF are identified and discussed. The product of this study is a conceptual model of how risks to the WQF of BHRE are produced and how the risk and associated uncertainties can be quantified.     

A Critical Review of Environmental Impact Statements in Sri Lanka with Particular Reference to Ecological Impact Assessment

This article critically reviews environmental assessment (EA) practices in Sri Lanka, with a particular focus on ecology. An overview is provided of the domestic and international influences which have shaped the administrative process which is currently a two-tiered scheme. An Initial Environmental Examination (IEE) provides a preliminary screening tool, prior to the requirement for a full Environmental Impact Assessment (EIA). A comprehensive survey of Sri Lankan national archives showed that 463 EAs were completed in the period 1981–2005, with the bulk of these in the more populated Western and North Western Provinces. Two-thirds were IEE surveys, while the remaining third advanced to full EIA. A representative sample of 130 EAs (both IEEs and full EIAs) spanning a broad range of project types, scales, and environmental settings was selected to evaluate the quality of the ecological investigations within the published environmental impact statements (EISs). These were assigned into five classes of “explanatory power”, on the basis of their scientific content in relation to survey, analysis, and reporting of ecological interests. Within most EISs, the ecological impact assessment (EcIA) was restricted to the lowest two categories of ecological assessment, i.e., tokenistic presentation of reconnaissance-level species lists without further analysis of the development implications for individual organisms or communities. None of the assessments reviewed provided statistically rigorous analysis, which would be required if ecological impact studies are to include quantitative and testable predictions of impact, which could then be followed up by appropriate post-impact monitoring programs. Attention to key local issues such as biodiversity or ecosystem services, which also have strong social dimensions in the developing world, was also notably underrepresented. It was thus concluded that despite the existence of a sound legislative framework in Sri Lanka, the analysis contained within EISs generally fails to convey meaningful information to the relevant stakeholders and decision makers involved in protecting ecological interests and promoting sustainable development. The introduction of strategic environmental assessment (SEA) is considered an important tool to strengthen the institutional capacity of Sri Lankan government to implement current regulations and, in particular, to combat the cumulative effects of incremental development.     

Using Ecological Risk Assessment to Identify the Major Anthropogenic Stressor in the Waquoit Bay Watershed,Cape Cod,Massachusetts

The Waquoit Bay Watershed ecological risk assessment was performed by an interdisciplinary and interagency workgroup. This paper focuses on the steps taken to formulate the analysis plan for this watershed assessment. The workgroup initially conducted a series of meetings with the general public and local and state managers to determine environmental management objectives for the watershed. The workgroup then decided that more information was needed on the impacts of six stressors: nutrient enrichment, physical alteration of habitat, altered freshwater flow, toxic chemicals, pathogens, and fisheries harvesting. Assessment endpoints were selected to establish the link between environmental management objectives, impacts of stressors, and scientifically measurable endpoints. The following assessment endpoints were selected: estuarine eelgrass cover, scallop abundance, finfish diversity and abundance, wetland bird distribution and abundance, piping plover distribution and abundance, tissue contaminant levels, and brook trout distribution and abundance in streams. A conceptual model was developed to show the pathways between human activities, stressors, and ecological effects. The workgroup analyzed comparative risks, by first ranking stressors in terms of their potential risk to biotic resources in the watershed. Then stressors were evaluated by considering the components of stressors (e.g., the stressor chemical pollution included both heavy metals and chlorinated solvents components) in terms of intensity and extensiveness. The workgroup identified nutrient enrichment as the major stressor. Nutrient enrichment comprised both phosphorus enrichment in freshwater ponds and nitrogen enrichment within estuaries. Because phosphorus impacts were being analyzed and mitigated by the Air Force Center for Environmental Excellence, this assessment focused on nitrogen. The process followed to identify the predominant stressor and focus the analyses on nitrogen impacts on eelgrass and scallops will serve as an example of how to increase the use of the findings of a watershed assessment in decision making.     

The evolving science of chemical risk assessment for land-applied biosolids

Biosolids, effluents, and manures are widely applied to agricultural land and other land with varying degrees of pretreatment or control. Regulations governing land application of biosolids take several broad forms in different countries, including limitations based on rates that do not lead to increases in background chemical concentrations or risk assessment approaches such as those used in the United States. Risk assessment is a process that is inherently limited by currently available information and practices, and consequently, risk-based land application limits must be reevaluated periodically. For complex mixtures such as biosolids, three principal categories of information will be affected by changing practices and scientific advances: (i) chemical constituents present in the material, (ii) the nature of expected exposures, and (iii) toxicity of the chemical constituents. New analytical methods and lower detection limits will affect chemical identification in wastes. Approaches to exposure assessment, such as increasing emphasis on probabilistic analyses, will continue to evolve, and exposure assumptions will change as new studies provide better data on factors such as soil ingestion, plant uptake of chemicals, and bioavailability of chemicals in soil. Similarly, toxicity assessments will be updated as new studies are conducted. The evolving science over the past decade is illustrated by comparing approaches used by the USEPA to assess human health and ecological risks for the Part 503 rule compared with the more recent evaluation of dioxins and related compounds in biosolids. While risks of chemicals in land-applied biosolids and other residuals need to be periodically re-evaluated, such re-evaluations may take forms other than full risk assessments.     

Designing Impact Assessments for Evaluating Ecological Effects of Agricultural Conservation Practices on Streams1

Abstract: Conservation practices are regularly implemented within agricultural watersheds throughout the United States without evaluating their ecological impacts. Impact assessments documenting how habitat and aquatic biota within streams respond to these practices are needed for evaluating the effects of conservation practices. Numerous sampling protocols have been developed for monitoring streams. However, protocols designed for monitoring studies are not appropriate for impact assessments. We developed guiding principles for designing impact assessments of ecological responses to conservation practices. The guiding principles are as follows: (1) develop the hypothesis first, (2) use replicated experimental designs having controls and treatments, (3) assess the habitat and biological characteristics with quantitative and repeatable sampling methods, (4) use multiple sampling techniques for collecting aquatic organisms, and (5) standardize sampling efforts for aquatic organisms. The guiding principles were applied in designing a study intended to evaluate the influence of herbaceous riparian buffers on channelized headwater streams in central Ohio. Our example highlights that the application of our recommendations will result in impact assessments that are hypothesis‐driven and incorporate quantitative methods for the measurement of abiotic and biotic attributes.     

韦伯-费希纳定律在区域生态环境质量评价中的应用

文章利用韦伯-费希纳定律建立区域生态环境评价的新模型,并通过实例研究了区域生态环境质量状况,即巢湖流域总体以及分区巢湖市、六安市的生态环境质量为Ⅵ级、分区合肥市为Ⅲ级。与未确知测度评价方法进行比较,取得了满意的结果,实例应用表明:该评价模型结构严谨,评价结果合理,为区域生态环境质量评价提供了一种简单而适用的评价方法。     

生态系统评价:问题分析与研究展望

生态系统评价是当前生态学研究中的一个热点和难点，它能够为区域生态系统健康检测、优良生态系统类型筛选、土地利用格局合理配置以及生态服务功能优化提供宝贵的参考和决策依据。论述了生态系统评价的相关内容、研究的尺度问题以及目前相配套的研究方法，分析了其中存在的诸多问题，简明指出了今后的工作重点和努力方向，并展望了生态系统评价的未来走向。认为今后综合性的生态系统评价以及与此相配套的评价方法需要得到大力加强和研发，同时生态系统评价应该和区域水土流失治理、生态安全和可持续发展等重大问题紧密结合。     

Treatment of risk in environmental impact assessment

Risk assessment and environmental impact assessment have developed as separate traditions. While environmental impact assessment is a broad field that includes all activities that attempt to analyze and evaluate the effects of human and related actions on the environment, risk assessment has been concerned with the relatively well-defined regulatory problems and employs formal quantitative analysis of the probability of specific undesired events, such as cancer. Risk analytic approaches, particularly the explicit treatment of uncertainty, can significantly contribute to environmental assessments. This article discusses the type and sources of uncertainty in environmental assessments, techniques for their quantification, and ways to use uncertainty estimates to calculate probabilities of effects or probabilities of exceeding environmental standards and to determine the need for mitigation or additional research.This article was presented at the International Institute of Applied Systems Analysis, Task Force Meeting on Risk and Policy Analysis under Conditions of Uncertainty, Laxenburg, Austria, November 1985.