EwE模型在水生态系统中的应用研究及长潭水库案例分析

EwE（Ecopath with Ecosim）模型是一种用于定量研究水生态系统食物网结构和能量流动特征的模型。总结了EwE模型中Ecopath、Ecosim、Ecospace和Ecotracer模块的原理，综述了该模型在不同类型水生态系统中的应用研究进展，发现Ecopath可用来评估海洋和淡水生态系统的成熟度并确定关键种和生态容量，明确浮游植物生产量（P）对生态系统总通量（TST）的重要贡献；Ecosim用于在时间尺度上揭示关键种捕捞、港口建设等人类活动对生态系统结构和功能的影响机制；Ecospace可用来阐明海上平台建设、发电厂运行、火山爆发等外部因素影响下渔业经济和生态系统结构的空间差异性；Ecostracer可用来追踪同位素、重金属和新型污染物等物质在食物网中的迁移过程。采用Ecopath分析了长潭水库的营养结构和能量流动，结果表明，长潭水库营养级介于1.000~3.093，食物网结构简单，TPP/TR为2.445，是一个相对成熟的生态系统，能量传递效率较低。未来应加强气候变化和人类活动对水生态系统结构演替的影响研究，推进新污染物在食物网中富集特征研究，为水域生态系统健康状态评估和渔业经济发展政策的调整提供支撑。

Research on the application of EwE model in aquatic ecosystems and a case study of Changtan Reservoir

Ecopath with Ecosim (EwE) model is commonly used to quantitatively study the food web structure and energy flow characteristics in the aquatic ecosystem. The principles and progress of Ecopath, Ecosim, Ecospace, and Ecotracer modules of EwE model and its application in different types of aquatic ecosystems were summarized. The results indicated that Ecopath could be used to estimate the maturity of the ocean and freshwater ecosystems, to determine key species and ecological capacity, and to clarify the important contribution of phytoplankton production (P) to total system throughput (TST) in the aquatic ecosystem. Ecosim was used to reveal the impact mechanisms of human activities (e.g. keystone species catching, port construction) on ecosystem structure and function on a time scale. Ecospace was used to clarify spatial variability of fishing activity and ecosystem structure under external factor effects (e.g. offshore platform construction, power plant operation, and volcanic eruption). Ecotracer was used to trace the immigration progress of isotopes, heavy metal, new pollutant, and other matters in the food web. Combined with Ecopath, the nutrient structure and energy flow of Changtan Reservoir were analyzed. The results showed that the trophic level was in the range of 1.000-3.093, indicating a simple food web structure. The total primary production/total respiration (TPP/TR) value was 2.445, indicating Changtan Reservoir was a relatively mature ecosystem, and it had a low energy transfer efficiency. In the future, studies on the impacts of climate change and human activities on the structural succession of aquatic ecosystems, and the enrichment characteristics of new pollutants in the food web should be strengthened to provide a scientific basis for the assessment of aquatic ecosystem health and the adjustment of fishery economic development policies.