太湖流域上游河流污染空间分布特征研究

为把握太湖流域上游西北部河网区域水体的N、P污染特征及其空间分布，2010年8月在该区域内的武进港 直湖港水系、洮滆水系、丹扁孟河（丹金溧漕运河、扁担河及孟津河）以及宜溧河水系的河网，监测了39个河流断面的水质。研究表明，4水系TN平均浓度分别为388、283、291及193 mg/L，DTN占TN比重分别为9180%、7843%、7001%及8444%，河网氮输出均以DTN为主。在DTN中NO-3 N浓度所占比重分别为6747%、5275%、7748%及4281%，NH+4 N浓度所占比重分别为1633%、3316%、1127%及4351%。TP平均浓度分别为059、030、026及015 mg/L，DTP所占比重分别为6213%、4019%、4673%及3197%，而PO3-4 P浓度占DTP比重分别为2073%、5461%、4327%及7772%。武进港 直湖港水系N平均浓度显著（〖WTBX〗p〖WTBZ〗<001）高于宜溧河水系，与其它两水系无显著差异，P平均浓度显著（〖WTBX〗p〖WTBZ〗<005）高于宜溧河水系和丹扁孟河，与洮滆水系无显著差异。影响太湖流域上游西北部区域河流水网水质的主导因素为氮污染，而其中以DTN污染最为严重。太湖西北部是蓝藻水华暴发的重灾区，上游区域DTN的大量输入，将成为引发太湖水体生态系统灾变的潜在风险

SPATIAL DISTRIBUTION CHARACTERISTICS OF UP-STREAM RIVER POLLUTION IN LAKE TAIHU BASIN

In order to investigate spatial distribution characteristics of nitrogen and phosphorus in up-stream rivers in Lake Taihu Basin beside the northwest part of the lake,water qualities of 39 rivers were monitored in the water systems of Wujin-Zhihu Port,Taoge,River Danbianmeng(Danjinlicao,Biandan and Mengjin) and Yilihe in August of 2010.Our study showed that the average concentrations of TN in the four water systems were 3.88 mg/L,2.83 mg/L,2.91 mg/L and 1.93 mg/L respectively.The proportions of DTN in TN were 91.80%,78.43%,70.01% and 84.44% respectively,so that DTN was the major nitrogen pollution components in the water systems.The proportions of NO-3-N in DTN were 67.47%,52.75%,77.48% and 42.81% respectively,and the proportions of NH+4-N in DTN were 16.33%,33.16%,11.27% and 43.51% respectively.The average concentrations of TP were 0.59 mg/L,0.30 mg/L,0.26 mg/L and 0.15 mg/L respectively,and the proportions of DTP in TP were 62.13%,40.19%,46.73% and 31.97% respectively.The proportions of PO3-4-P in DTP were 20.73%,54.61%,43.27% and 77.72% respectively.The N and P pollution in the water system of Wujin-Zhihu Harbor is the most serious in the four water systems.The dominant pollution factor that influences the water quality of up-stream rivers in Lake Taihu Basin beside the northwest part of the lake was nitrogen,in which dissolved DTN was the major component.Since the northwest part of the lake is a disastrous area with heavy cyanobacterial bloom,large amount of DTN input to this part will be a potential risk for the ecosystem in the lake.