New ecosystem-based approaches to understand the risks to aquatic biodiversity from human activities

背景与理由随着多个国家的工业发展，淡水污染正在加剧，导致过去几十年的生态系统退化程度加剧(Förstner和Prosi，1979；Camargo，1994；Stauffer，2013)。与淡水生态系统退化相关的生物多样性下降将对生态系统服务产生越来越大的负面影响，例如清洁水供应、减少洪水以及对社会的娱乐效益(Wilson和Carpenter，1999；Aylward等人，2005；Dodds，Perkin和Gerken，2013)。为了在生态系统破坏变得不可逆转之前识别和避免破坏，目前的环境影响评估使用选定物种的生物指标来表示对整个生态系统的影响(De la Torre、Ferrari和Salibián，2002年；Hellawell，2012年)。然而，这一方法可能过于含糊，因为单一指标可能不能反映不同物种的整个群落的情况(McCarty，Power和Munkitrick，2002；Bartell，2006)。此外，物种内部个体对环境变化的反应可能由表型变异引起，这将限制使用个体来评估群落水平影响的有效性。纳入更多物种的生态风险评估方法可能是当前方法的关键改进，并在多种压力下提供生态系统破坏和崩溃的有效早期预警(Kford等人，2005年)。该项目旨在通过观察生物多样性与水生态系统中生态系统功能之间的关系，为更好地发展未来的生态风险评估提供循证信息。随着人类人口和发展的不断增加，本项目的成果可能有助于通过可持续发展更有效地保护生物多样性。研究问题本项目主要解决三个问题：1.淡水生物多样性指标与生态系统功能之间的关系，以及指标的选择如何影响生态系统健康变化的衡量标准？2.化学和其他压力对生态系统功能的影响是什么，是否有阈值效应的证据，以及是否有任何物种特征使它们极易遭受损失？3.在生态风险评估中，各种生态系统功能指标的稳健性是什么，这些措施中的哪一项是整个生态系统反应的可靠衡量标准，可以为生态系统破坏提供早期预警？

Background & RationaleFreshwater pollution is increasing in line with industrial development in multiple countries, with higher levels of ecosystem degradation over past decades as a result (Förstner and Prosi,1979; Camargo, 1994; Stauffer, 2013). Decline in biodiversity associated with freshwater ecosystem degradation will have increasing negative impacts on ecosystem services, such as clean water supply, flood abatement as well as recreational benefits to society (Wilson and Carpenter, 1999; Aylward et al., 2005; Dodds, Perkin and Gerken, 2013). In order to identify and avoid ecosystem damage before it becomes irreversible, current environmental impact assessments use biological indicators from select species to represent the effects on an entire ecosystem (de la Torre, Ferrari and Salibián, 2002; Hellawell, 2012). However this may be too vague of an approach, as single indicators may not reflect that of an entire community of varying species (McCarty, Power and Munkittrick, 2002; Bartell, 2006). In addition, inherent variation in individual responses within a species to environmental change, which could be caused by phenotypic variability, would limit the effectiveness of using individuals to gauge community level effects.Ecological risk assessment approaches that include more species could be a key improvement in current methods, and provide effective early warnings of ecosystem damage and collapseunder a multitude of pressures (Kefford et al., 2005).This project will aim to provide evidence-based information to better develop future ecological risk assessments by observing the relationships between biodiversity and ecosystem function infreshwater ecosystems. The outcome of this project could contribute to conserving biodiversity more effectively through sustainable development as human population and development continues to increase.Research QuestionsThis project is addressing three main questions:1. What are the relationships between indicators of freshwater biodiversity and ecosystem functions within eco-regions, and how can the choice of indicator affect the measure of change in ecosystem health?2. What is the impact of chemical and other stressors on ecosystem function, is there any evidence of threshold effects, and do any species traits make them highly vulnerable to loss?3. What is the robustness of various ecosystem function indicators within ecological risk assessments, and which of these would be reliable measures of whole ecosystem response that could provide early warnings of ecosystem damage?