重庆市水库富营养化调查及评价

Investigation and Evaluation of Rreservoir Eutrophication in Chongqing

通过对重庆市36座水库的监测,各水库chla值范围为1.59～52.3 mg/m3;TP范围为0.002～0.598 mg/L;TN范围为0.52～5.94 mg/L;SD范围为0.48～3.2 m;COD Mn范围为0.75～9.3 mg/L.COD Mn、TN与chla之间呈极显著的正相关关系,SD与chla呈极显著的负相关关系,TP与chla的相关性较差,利用回归分析得出TN、SD、COD Mn与chla的线性关系.利用修正的卡尔森指数对水库进行富营养化评价,结果表明:35座大中型水库达到富营养化的水库为27座,达到中营养的8座,贫营养水库无.通过对富营养化水库分布分析,位于三峡库区生态经济区的水库富营养化状况比都市区和渝西地区轻.对重庆市3座大型水库的营养盐输出作了初步估算,对比三峡库区城市污水口营养盐排放量,表明仅3座大型水库排放的TN超过67个城市污水口排放量,TP排放占城市污水排放量的16%.

The 36 reservoirs were investigated in Chongqing, concentration of.chlorophyll a is 1.59-52.3 mg/m^3;TP is 0.002-0.598 mg/L;TN is 0.52-5.94 mg/L;SD is 0.48-3.2 m; CODMn is 0.75-9.3 mg/L.There are significant positive correlation between CODMn,TN and chlorophyll-a, SD was significantly negative with chlorophyll-a, correlation between TP and chlorophyll-a was weak, the relation of chl0rophyll-a, total phosphorus and transparency are showed by using regression method, corrected Carlson Trofic State Index are used to evaluate the eutrophication degree of 35 reservoirs, 27 reservoir were eutropher and 8 reservoir were mesotropher.Eutrophication condition of the reservoir in main city and west of Chongqing were more serious than which in Three gorges reservoir area. Nutrient output of 3 huge reservoirs were calculated and were contrasted with 67 sewage limbers, the amount of total nitrogen output only the 3 reservoirs were exceeded to 67 sewage and output of total phosphorus were about 16 percent occupied sewage.