Ecological risk assessment and food webs: multiple stressor effects on biodiversity and ecosystem function

生态风险评估用于确定人类对环境造成不利生态影响的可能性。大多数监管毒性研究衡量化学品对单个生物体的影响，而不考虑对更高水平的生物组织的影响，包括生物多样性、生态系统功能和生态系统服务。其假设是，通过根据在标准化条件下暴露于单一化学品的敏感类群的个体水平端点做出监管决定，提供生态系统服务的生态系统的生物多样性和生态功能也将得到保护。尽管基于标准毒性研究的监管评估旨在保护生态生物多样性，但它们并不是为了预测，也没有任何支持性证据表明它们对生态系统功能的保护程度。因此，有必要开发方法，能够将经常测量的(即，单一化学品对单个生物体的影响)外推到我们想要保护的东西(即，支撑生态系统服务提供的生物多样性和生态系统功能)，并在更现实、更多应激源的背景下考虑化学品的风险。这是生态毒理学研究的一个重要和基本目标，特别是在全球气候变化的背景下。

Ecological risk assessment is used to determine the likelihood of adverse ecological effects resulting from human impacts on the environment. Most regulatory toxicity studies measure the effect of chemicals on individual organisms and do not consider impacts on higher levels of biological organisation, including biodiversity, ecosystem function and ecosystem services. The assumption is that by basing the regulatory decision on individual-level endpoints of sensitive taxa exposed to single chemicals under standardised conditions, the biodiversity and ecological functions of ecosystems that deliver ecosystem services will also be protected. Although regulatory assessments based on standard toxicity studies are intended to be protective of ecological biodiversity, they are not intended to be predictive nor is there any supportive evidence of how protective they are of ecosystem function There is a need, therefore, to develop approaches that enable the extrapolation of what has been frequently measured (i.e. the effects of single chemicals on individual organisms) to what we want to protect (i.e. biodiversity and ecosystem functions underpinning ecosystem service delivery) and that consider the risk of chemicals in a more realistic, multi-stressor context. This is an important and fundamental objective for ecotoxicological research, especially in the context of global climate change.