生態風險評估之發展及應用

Development and Application of Ecological Risk Assessment

陳士賢(Colin S. Chen)

《生物科學》 47卷1期 (2004/12) Pp. 64-84

https://doi.org/10.29981/CB.200412.0005

摘要

環境風險評估及風險管理之架構模式在過去十年來被發展出用於描述環境衝擊，是先進國家最重要的環境政策之一，其中生態風險評估為隸屬於環境風險評估之一種系統分析方法，旨在推導出生態系暴露於物理、化學及生物性壓力下所承受的風險，乃是綜合生態學、環境化學、環境毒理學、土壤學、水文學及其他地球科學的原則，來估計非期望性之生態事件，在特定條件下發生的機率。本文目的在於介紹生態風險評估之演進，描述先進國家應用生態風險評估於新化合物生產及進口、農藥製造、危害性廢棄物污染場址、水質評估及外來種生物之實施原則，生態風險評估實施步驟及彙整國內相關案例研究。生態風險評估之工作架構分成三階段，首先為問題之形成及歸納，確認生態衝擊來源、特性與影響，規劃評估標的與終點，建立概念模式及現地調查與實驗，其次為分析階段，進行生態衝擊暴露及生態衝擊效應分析，最後為風險特性界定，推估生態風險，及藉由科學分析方法來描述風險。其過程可依據資料充足性、不確定性、目標需求、時效性及經費考量，必要時執行多層次之重覆評估程序。最後評估結果仍需與風險管理者溝通，以利後續執行風險之削減及改善。國內提倡及推行生態風險評估期間尚短，預期將來此類型研究會顯著增加，其所累積之資料與結果將可提供環境管理者決策參考。

關鍵字

生態風險評估 ； 問題之形成及歸納 ； 分析 ； 風險特性界定

並列摘要

Risk assessment/risk management is one of the most important environmental policy developments of the past decade. The impacts of human activities on natural resources must be measured and assessed against a natural ecological background at different spatial and temporal scales. Ecological risk assessment is designed to meet this need. Ecological risk assessment is a process that evaluates the likelihood that adverse ecological effects may occur or are occurring as a result of exposure to one or more physical, chemical, or biological stressors. It uses methods of system analysis to integrate aspects of ecology, environmental chemistry, environmental toxicology, hydrology, and other earth sciences to estimate conditional probabilities of the occurrence of undesired ecological events. The objectives of this publication are to describe development and processes in ecological risk assessment, to provide examples of the existing uses of ecological risk assessment in areas of new industrial chemicals, pesticides, hazardous waste contaminated sites, water quality, and exotic species, and to highlight a case study overview in Taiwan. Ecological risk assessment includes three primary phases: problem formulation, analysis, and risk characterization. In problem formulation, risk assessors evaluate goals and select assessment endpoints, prepare the conceptual model, and develop an analysis plan. During the analysis phase, assessors evaluate exposure to stressors and the relationship between stressor levels and ecological effects. In the third phase, risk characterization, assessors estimate risk through integration of exposure and stressor-response profiles, describe risk by discussing lines of evidence and determining ecological adversity, and prepare a report. Risk assessors describe risk by evaluating the evidence supporting or refuting the risk estimates and interpreting the observed effects on the assessment endpoints. Agreement among different lines of evidence of risk increases confidence in the conclusions of a risk assessment. The interface among risk assessors, risk managers, and interested parties during planning at the beginning and communication of risk at the end of the risk assessment is critical to ensure that results of the assessment can be used to support a management decision. Currently studies related to ecological risk assessment are not widely conducted in Taiwan. However, the broad applicability of ecological risk assessment by demonstrating a flexible and problem-solving paradigm that can support environmental decision-making to address a wide array of environmental issues is anticipated.

並列關鍵字

Ecological risk assessment ； Problem formulation ； Analysis ； Risk characterization