城市雨水塘生态风险评价方法

Overview on Ecological Risk Assessment Methodologies of Urban Stormwater Ponds

雨水塘已广泛用于城市雨洪管理实践中,并成为城市景观的重要组成部分。但作为受纳水体,雨水塘长期暴露于人类活动所造成的压力源中,易表现出生态脆弱性和易损性,雨水塘生态风险评价有助于提高生物多样性的保护与恢复。虽然沉积物质量评价"三元法"(sediment quality triad,SQT)等多学科综合评价方法已得到广泛应用,但其因参照站位选取问题并不适合于雨水塘生态系统,同时评价结果缺少一致性与特异性。研究提出更科学、有效的综合评价方法用于识别并确定雨水塘的生物状态,对于掌握城市雨水塘处理雨水径流的潜在生态风险具有重要的意义。为此,笔者回顾了城市雨水塘生态风险评价研究进展,从参照站位角度分析了现有基于底栖生物的生物评价法存在的局限性。介绍了2类生态质量功能目标的定义以及寡毛类动物指数法(oligochaete index methodology,OIM)结合其三基元(即OIM-SQT)的综合评价方法,并对该方法在生态质量目标概念框架中的应用前景与研究领域进行了展望,提出应用该方法解决参照站位选取问题并形成标准化的操作规程是未来的重点研究方向。

Stormwater ponds,which are widely used in the practice of urban stormwater management,have become common features of the urban landscape.While,as open receiving water systems,stormwater ponds are exposed to strong anthropogenic pressures,and then prone to show as ecological fragility and vulnerability.Therefore,assessing the ecological risks of stormwater facilities is crucial for ensuring both the preservation and rehabilitation of biodiversity in urban areas.Although,the application of established integrated assessment methodologies,such as the sediment quality triad(SQT),is widely used around the world,the selection of reference sites and lacked adoption of integrated interdisciplinary approaches with consistency and specificity is challenged by the man-made features of urban stormwater ponds.The search for a more scientific and effective integrated assessment methodology to define and confirm the biological status of stormwater ponds ecosystem has great significance to understand the potential ecological risks of stormwater.Therefore,current research in the field of ecological risk assessments of urban stormwater ponds is reviewed at first,and limitation of current approaches based on benthos is analyzed on the aspect of reference sites.And on this basis,two definitions of ecological quality functional objectives,and the benefits and prospects of supplementing the SQT with the oligochaete index methodology(OIM)adapted to the conceptual framework of ecological quality goals are introduced.We suggest that future researches on ecological risk assessment of urban stormwater pond should focus on integrated interdisciplinary approaches with independence(or less dependence)on reference sites from the perspective of the definitions of ecological objectives,and the development of standardized protocols.