乌梁素海水质变化特征

目的]研究乌梁素海水质变化特征和污染物浓度的时空分布。方法]利用2014—2016年乌梁素海12个采样点的实测数据,选取TN、NH_3-N、TP、COD这4项污染指标,分析其水质变化特征和污染物浓度的时空分布。结果]近3年来乌梁素海的水质逐年改善,由于芦苇等植物吸收过滤及沿途污染物的物理沉降等,由西北部入湖地区各点向湖心和西南部出湖地区的污染物浓度降低;污染物浓度随时间变化明显,TN、NH_3-N、TP、COD浓度整体体现出1月(枯水期)浓度较高,5月(平水期)最低,9月(丰水期)污染物浓度普遍重新回升。污染物浓度与气温和蒸发量无显著相关,与降水量相关,且湖泊水质主要与农田退水有关。结论]该研究为乌梁素海水污染治理和环境管理提供科学依据。

Variation Characteristics of Water Quality in Wuliangsuhai Lake

Objective] The research aimed to study the change characteristics of water quality and the spatiotemporal distribution of pollutant concentrations in the Wuliangsuhai Lake.Method]Based on the measured data from 12 sampling sites of Wuliangsuhai Lake from 2014 to 2016, four pollution indicators were selected including TN,NH3-N,TP and COD to analyze the water quality characteristics of Wuliangsuhai Lake and the spatiotemporal distribution of pollutant concentration.Result]In the past three years,the water quality of Wuliangsuhai Lake had been im-proving year by year.Due to the absorption and filtration of plants such as reeds and the physical settlement of pollutants along the way,the con-centrations of pollutants from the northwestern lake into the lake and the southwestern part of the lake had decreased;The concentrations changed significantly with time.The concentrations of TN,NH3-N,TP and COD showed a higher concentration in January(dry season) and the lowest in May (flat water period).The concentration of pollutants in September (flooded season) generally recovered.There was no significant correla-tion between pollutant concentration and temperature and evaporation,and it was related to precipitation.The quality of lake water was mainly re-lated to farmland water withdrawal.Conclusion]The study provided scientific basis for Wuliangsu seawater pollution control and environmental management.