Xu F L, Tao S, Dawson R W, Li P G, Cao J
Department of Urban and Environmental Sciences, Peking University, Beijing, China.
Water Res. 2001 Sep;35(13):3157-67. doi: 10.1016/s0043-1354(01)00040-9.
A set of ecological indicators including structural, functional, and system-level aspects were proposed for a lake ecosystem health assessment, according to the structural, functional, and system-level responses of lake ecosystems to chemical stresses including acidification, eutrophication and copper, oil and pesticide contamination. The structural indicators included phytoplankton cell size and biomass, zooplankton body size and biomass, species diversity, macro- and micro-zooplankton biomass, the zooplankton phytoplankton ratio, and the macrozooplankton microzooplankton ratio. The functional indicators encompassed the algal C assimilation ratio, resource use efficiency, community production, gross production/respiration (i.e. P/R) ratio, gross production standing crop biomass (i.e. P/B) ratio, and standing crop biomass unit energy flow (i.e. B/E) ratio. The ecosystem-level indicators conisisted of ecological buffer capacities, energy, and structural energy. Based on these indicators, a direct measurement method (DMM) and an ecological modeling method (EMM) for lake ecosystem health assessment were developed. The DMM procedures were designed to: (1) identify key indicators; (2) measure directly or calculate indirectly the selected indicators; and, (3) assess ecosystem health on the basis of the indicator values. The EMM procedures were designed to: (1) determine the structure and complexity of the ecological model according to the lake's ecosystem structure; (2) establish an ecological model by designing a conceptual diagram, establishing model equations, and estimating model pararmeters; (3) compare the simulated values of important state variables and process rates with actual observations; (4) calculate ecosystem health indicators using the ecological model; and, (5) assess lake ecosystem health according to the values of the ecological indicators. The results of a case study demonstrated that both methods provided similar results which corresponded with the lake's actual trophic state.
根据湖泊生态系统对包括酸化、富营养化以及铜、石油和农药污染在内的化学胁迫的结构、功能和系统层面的响应，提出了一套包括结构、功能和系统层面等方面的生态指标，用于湖泊生态系统健康评估。结构指标包括浮游植物细胞大小和生物量、浮游动物体型和生物量、物种多样性、大型和微型浮游动物生物量、浮游动物与浮游植物的比例以及大型浮游动物与微型浮游动物的比例。功能指标包括藻类碳同化率、资源利用效率、群落生产力、总生产/呼吸（即P/R）比、总生产与现存生物量（即P/B）比以及现存生物量与单位能量流（即B/E）比。生态系统层面的指标包括生态缓冲能力、能量和结构能量。基于这些指标，开发了用于湖泊生态系统健康评估的直接测量方法（DMM）和生态建模方法（EMM）。DMM程序旨在：（1）识别关键指标；（2）直接测量或间接计算所选指标；以及（3）根据指标值评估生态系统健康状况。EMM程序旨在：（1）根据湖泊的生态系统结构确定生态模型的结构和复杂性；（2）通过设计概念图、建立模型方程和估计模型参数来建立生态模型；（3）将重要状态变量和过程速率的模拟值与实际观测值进行比较；（4）使用生态模型计算生态系统健康指标；以及（5）根据生态指标的值评估湖泊生态系统健康状况。案例研究结果表明，这两种方法得出的结果相似，且与湖泊的实际营养状态相符。
