滆湖及长荡湖区域磷污染源数值解析与评估

Numerical Simulation and Assessment of Phosphorus Pollution Sources in Lake Gehu and Lake Changdang

针对太湖流域典型区域滆湖、长荡湖区域总磷污染问题,采用流域—区域尺度嵌套的数学模型模拟方法,开展面源磷污染负荷时空分布特性数值模拟与评估,分析了区域内工业、生活、林业三种行业类型面源污染特征。结果表明,滆湖、长荡湖区域工业、生活、林业面源磷污染负荷总量为100.32 t/a;从空间分布特征来看,两湖区域面源磷污染高风险区为武进区的武南小流域、宋剑湖小流域、横林小流域和金坛区的华兴小流域、城区小流域;从行业分布特征来看,滆湖、长荡湖区域工业面源磷污染占比最高,生活面源次之,林业面源占比最低,三种类型面源磷排放对区域总磷污染的贡献比为75∶22∶3,工业、生活及林业面源磷污染排放均表现出第三季度明显高于其他季度的特征。

Focusing on the problem of total phosphorus pollution in the typical areas of Gehu Lake and Changdang Lake in Taihu Lake Basin,the numerical simulation and evaluation of the spatial and temporal distribution characteristics of non-point source phosphorus pollution load were carried out by using the nested mathematical model simulation method at the basin-regional scale.The characteristics of non-point source pollution in the three industries of industry,life and forestry in the region were analyzed.The results show that the total non-point source phosphorus pollution load of industry,life and forestry in Gehu Lake and Changdang Lake was 100.32 t/a.From the perspective of spatial distribution characteristics,the high-risk areas of non-point source phosphorus pollution in the two lakes are Wunan small watershed,Songjian Lake small watershed,Henglin small watershed in Wujin District,Huaxing small watershed and urban small watershed in Jintan District.From the perspective of industry distribution characteristics,the proportion of industrial non-point source phosphorus pollution in Gehu Lake and Changdang Lake area is the highest,followed by domestic nonpoint source,and the proportion of forestry non-point source is the lowest.The contribution ratio of three types of nonpoint source phosphorus emissions to regional total phosphorus pollution is 75∶22∶3.The industrial,domestic and forestry non-point source phosphorus pollution emissions showed that the third quarter was significantly higher than other quarters.