In order to explore the internal conflict and synergy among water pollution control, water conservation and socio-economic development, a system of coupling simulation for the aquatic environmental-economic system of lake watershed was constructed and applied at Yilong Lake Watershed. Based on the scenario analysis, the following conclusions are drawn. 1) Under the condition of economic and social affordability, the nutrient load of Yilong Lake can be reduced to the level of aquatic environmental capacity corresponding to Grade IV water quality through the measures of controlling the pollution. 2) The implementation of industrial relocation or very strict scale restriction is extremely unfavorable for gross domestic product (GDP) growth and urbanization of the watershed, but does not play a significant role in protecting the aquatic environment of Yilong Lake. 3) The critical measures in the planning period are to change the planting practices of high water-consuming and heavy fertilizer-using, treat rural domestic sewage more effectively, promote sewage reuse, and reduce the transfer of sewage. 4) According to the simulation results, the optional scheme selected by the approach proposed here would reduce the water diversion demand by 45%, and cut down the total nitrogen (TN) and total phosphorus (TP) discharged into the lake from the land surface by 26.6% and 18.5% respectively, and eliminate the TN and TP load of the lake by 20.7% and 17.5% respectively, but only at a cost of 7% of GDP at the end of the planning period.

为探索湖泊流域水污染治理、水资源节用与社会经济发展之间的冲突与协同关系, 提出水环境–经济系统耦合模拟方法, 并在异龙湖流域开展应用研究。基于情景分析结果, 得出如下结论: 1) 在经济社会可承受的范围内, 通过流域水污染控制, 可将异龙湖的入湖营养物负荷削减到IV类水质目标对应的水环境容量水平; 2) 实施工业搬迁或严格的规模限制对流域经济总量的增长和城镇化极为不利, 对异龙湖水环境的保护作用并不显著; 3) 规划期水污染防治的重点应是改变高水高肥的农业种植模式, 治理农村生活污水, 推行污水回用, 同时减少污水向外流域的转移; 4) 依据模拟结果, 给出的优化方案在规划期末可减少45%的外调水, 陆源TN和TP年入湖负荷分别降低 26.6%和18.5%, 湖泊TN和TP污染负荷分别降低20.7%和17.5%, GDP损失仅7%。