【摘要】 以千岛湖湖内重点监测断面高锰酸盐指数(COD_Mn)实测数据为基础,基于EFDC（environmental fluid dynamics code）模型构建适用于千岛湖的二维水质模型,通过设置不同情景方案,分析千岛湖上游入流和湖周入流COD_Mn变化对湖内COD_Mn的影响,解析边界COD_Mn和湖内重点监测断面COD_Mn间的响应关系,并定量计算上游入流COD_Mn变化对湖内重点监测断面COD_Mn的影响和贡献。结果表明:通过多组常降解系数平行模拟方法,确定千岛湖湖体COD_Mn的降解系数（k）为0. 001 5;上游入流COD_Mn与湖内重点监测断面COD_Mn之间存在显著的响应关系,当上游入流COD_Mn为6. 0 mg/L时,湖内威坪林场至三谭岛断面COD_Mn超过GB 3838—2002《地表水环境质量标准》Ⅱ类标准;上游入流响应系数明显大于湖周入流响应系数,上游入流对湖内威坪林场、小金山、三潭岛、大坝前4个重点监测断面COD_Mn的贡献率分别为82. 0%～92. 3%、73. 8%～88. 2%、53. 8%～62. 8%和57. 7%～76. 4%。上游入流是影响千岛湖湖内重点监测断面COD_Mn的主要因素,建议加强对上游入流的水质监测和污染控制。更多还原

【Abstract】 Based on the measured data of COD_Mnin the key monitoring sections of Qiandao Lake, a two-dimensional water quality model for Qiandao Lake based on the Environmental Fluid Dynamics Code（ EFDC）Model was established. The influence of inflow COD_Mnfrom upstream and the inflows around the lake on the COD_Mn in inner Qiandao Lake were analyzed by various scenarios. The response relation between the boundary COD_Mnand the COD_Mnat key monitoring sections in the lake was analyzed, and the influence and contribution of the upstream inflow COD_Mnvariation on the COD_Mnof the key monitoring sections in the lake were quantified. Results showed that the comprehensive degradation coefficient（ k） of COD_Mnin Qiandao Lake was 0. 001 5, according to the parallel simulation of several constant degradation coefficients. There existed an obvious response relation between the upstream inflow COD_Mnand COD_Mnin the key monitoring sections. When the upstream inflow COD_Mnwas 6 mg/L,COD_Mnbetween Weipinglinchang to Santandao sections exceeded Grade Ⅱ water quality standard of Surface Water Environmental Quality Standards（ GB 3838-2002）. Meanwhile, simulated results showed that the response coefficients of upstream inflows were obviously larger than that of inflows around the lake. The contribution rate of upstream inflows to COD_Mnin key monitoring sections of Weipinglinchang, Xiaojinshan, Santandao and Dabaqian was 82. 0%-92. 3%, 73. 8%-88. 2%, 53. 8%-62. 8% and 57. 7%-76. 4%, respectively. The impact of COD_Mn on key monitoring sections from upstream inflows was greater than the inflows around the lake. The results indicated that upstream inflows were the main factors affecting the COD_Mnof the key monitoring sections in Qiandao Lake.Therefore, the water quality monitoring and pollutant control should be strengthened for upstream inflows.更多还原