洞庭湖典型垸内沟渠水体富营养化评价

为研究平原湖区典型沟渠污染现状,选取洞庭湖南汉垸4条沟渠和1条外河为研究对象,首次开展沟渠水质富营养化评价。研究结果表明,湖区沟渠达到了中度重度富营养化水平,外河达到富营养化水平,沟渠富营养化程度明显高于外河,研究区域富营养化程度排序依次为:南阳渠>战备渠>莲子港电排渠>龙头嘴电排渠>西伏电排外河。沟渠各营养盐平均浓度均高于洞庭湖主湖区近20年平均浓度,沟渠水质污染对洞庭湖主湖区水质构成威胁,需切实加强湖区沟渠的清淤治理。

To research the present pollution status of typical ditches in the Plain Lake, the study estimated eutrophication assessments for four ditches and a river respectively in Nanhan Yuan, Dongting Lake. The results indicated that： the water quality of ditches and river was in the level of moderate nutrition and serious eutrophication respectively, and the eutrophic level in the ditches was more serious than that in the river. The eutrophic level of them are Nanyangqu〉Zhanbeiqu〉Lianzigangdianpaiqu〉Longtouzuidianpaiqu〉Xifudianpaiwaihe. The average concentration of nutrients from ditches was more serious than that of in the Dongting Lake for the past two decades. The pollution of water in ditches posed potential harmful effects on the water quality of the Lake Dongt- ing Lake, thus more measures should be strengthened in practice for the ditches of the lakes.