滇池水体理化环境状况时空分布格局研究

在滇池全湖设置了 4 0个采样点 ,从 2 0 0 2年 9月至 2 0 0 3年 8月 ,按每月一次的频度对滇池水体的pH、溶解氧、透明度、总磷、溶解性总磷、溶解性磷、总氮、氨氮、Chla进行了为期一年的监测。结果表明 ,滇池外海水质已属V类及超V类水质 ,重富营养程度 ,只能满足工业和农业供水水质要求。滇池外海水质存在区域性强的特点 ,其污染程度与该地区的工农业分布格局相关 ,西北部水质污染情况最为严重 ,北部次之 ,南部最轻 ;在不同月份水质存在明显差异 ,在汛期 (5— 9月份 )水质污染最为严重 ,冬春季节则较轻。本研究初步揭示了滇池污染的现状及时空分布规律 ,为分区域治理滇池水污染提供了科学依据

THE SPATIO-TEMPORAL OF WATER ENVIRONMENTAL STATUS IN DIANCHI LAKE

After decades of economic reform and booming industry development,a tremendouds amount of pollutant were discharged into the Dianchi lake and the lake is suffered from severe eutrophication. In order to investigate the pollution situation of the Dianchi lake,forty sampling locations were set at Waihai of the Dianchi Lake and pH,DO,transparency,total-P,dissolved total-P,dissolved-P,total-N,NH 3-N and Chla were analyzed monthly from Sep. 2001 to Aug. 2002. Four areas were defined geographical and each contains several sampling stations. They are the northwest area(sampling locations of 1-3),the north area(4-15),the middle area(16-25)and the south area(26-40). The results showed that the water quality of Waihai in Dianchi lake was worse than the standard of V level(Environmental quality standards for surface water),fell into the super-eutrophication state,only suitable for industry and agriculture use. Generally,the pollution status is as following,the northwest area was the worst,the north area was worse,the middle area was bad,then the south area. In addition,the spatial distribution of pollution was correlative with the industry and agriculture distributions. Although the concentrations of total-P,dissolved total-P,dissolved-P,total-N and Chla were the highest in the northwest area,and declined southwestward,a peak value of total-P was observed at the east part of the north area,and two peak values of dissolved-P were observed at the south area and the west part of the middle area. The contaminative degree was various greatly in different months, the concentrations scopes of total-N is from 1.11 to 10.27mg/L, total-P from 0.074 to 0.573mg/L, and Chla from 0.0136 to 0.327mg/L. It was observed that the pollution was worst in flood season (May to Sept.),while in winter and spring, the pollution was relatively better. The paper showed the pollution status and spatio-temporal distribution of pollution of Dianchi lake, which provided for the theoretic reference of divisional treatment Dianchi lake pollution. At last, the paper discussed the cause of eutrophication of the Dianchi lake, and gives some advice on the possible eutrophication prevention.