基于物种敏感性分布法的生态风险评价研究进展

生态风险评价是认识生态健康和污染物可能对生态环境产生不良影响的重要手段,而物种敏感性分布法是使用较为广泛的评价方法,其核心步骤是筛选出合适物种的毒性数据进行曲线拟合。在简要介绍物种敏感性分布法原理和步骤的基础上,综述了物种敏感性分布法应用的几个关键问题,即物种筛选、毒性数据选择和拟合模型确定。针对特殊水体,提出了基于区域同类型水环境物种对比的物种筛选法和基于水环境历史物种比较的物种筛选法。最后对未来的研究工作进行了展望,指出现有研究的不足和未来研究的方向。

Research advances in the ecological risk assessment based on the species sensitivity distributions

The given paper is inclined to make a review of research advances in the ecological risk assessment approaches to recognizing the conditions of the ecological health and the adverse effects involved on the ecological environment due to all sorts of pollutants.For example,species sensitivity distributions (SSDs) can be taken as one of the most widely used methods to assess the ecological risks.With the given approach,it is possible for us to gain the cumulative probability distributions of the chemical toxicity data from the single-species bioassays of various species.The key assumption for the application of the SSDs is that it is necessary to take the toxicity data of the available species to represent a random sample from a statistical distribution that is representative of a community or ecosystem in the concept that the limited toxicity testing data of only a few species can be used to extrapolate to a community level to protect a certain portion of species in an ecosystem.Thus,it can be seen that,the principle of SSDs can let us divide its application into five steps as follows:(1) collecting and screening the toxicity data of chemicals;(2) determining the optimal fitting model;(3) fitting the SSDs curves;(4) working out the PAF and HC5;(5) assessing the ecological risks that may be caused by.Among the above mentioned steps,the first two are decisive and critical.In this review,we would also like to choose the following three key issues for application of SSDs as the main topics for discussion:(1) how to select the appropriate species;(2) how to screen and preprocess toxicity data of the selected species;(3) how to determine the fittest model.Particularly speaking,it is necessary to propose the available ways for selecting the fit species based on comparison of the regional same type of the aquatic environment and the historical species in the aquatic environment for certain special water bodies,providing new ideas for the ecological risk assessment based on the SSDs.In addition,we have also chosen a few.principles and methods and introduced preprocessing ecotoxicological data for further exploration,such as the principle to use the geometric means for all the raw data and the methods for transforming the acute toxicity data into the chronic ones,whereas we have made all the parametric and nonparametric models of fitting SSDs curves to help to find out the best suitable models.And,finally,we have also illustrated all the inadequacies of the existing studies and described new trends of the future studies so as to provide an essential basis and technical guidance to the further development of SSDs in the ecological risk assessment.