城市富营养化湖泊水质对降雨的响应——以武汉东湖为例  

Response of water quality of urban eutrophic lakes to rainfall:a case study of Wuhan East Lake

作　　者：胡胜华 李鑫 李小辉 孙紫童 周汉娥 熊雄[2] 吴辰熙[2] Hu Shenghua;Li Xin;Li Xiaohui;Sun Zitong;Zhou Han'e;Xiong Xiong;Wu Chenxi(Wuhan Bridge Engineering Co.,Ltd.,Wuhan 430071,China;Institute of Hydrobiology,Chinese Academy of Sciences,Wuhan 430072,China;Wuhan Hangfa Ruihua Ecological Technology Co.,Ltd.,Wuhan 430063,China)

机构地区：[1]武汉市桥梁工程有限公司,武汉430071 [2]中国科学院水生生物研究所,武汉430072 [3]武汉航发瑞华生态科技有限公司,武汉430063

出　　处：《河南师范大学学报(自然科学版)》2025年第3期50-57,共8页Journal of Henan Normal University(Natural Science Edition)

基　　金：国家自然科学基金(52070190);武汉市市政建设集团有限公司科技计划(wszky202014).

摘　　要：降雨是湖泊营养盐输入的重要途径,为了摸清降雨前后城市湖泊水质变化特征,选择典型城市富营养化湖泊武汉东湖为研究对象,在全湖布设27个样点,于2021年9至10月期间采集表层沉积物样品,并对期间降雨前后11个水质指标进行监测,识别表层沉积物氮磷污染现状与降雨前后东湖水质变化特征,利用线性回归、主成分分析等方法分析造成降雨前后水质差异的原因.结果表明,武汉东湖表层沉积物全氮、总磷平均含量分别为4065、683 mg/kg,总体处于重度污染水平.与雨前相比,雨后表层水体浊度、总磷、溶解性总磷、活性磷酸盐显著升高(P<0.05),溶解氧、pH、硝态氮显著降低(P<0.05),但总氮和溶解性总氮无显著性差异(P>0.05).雨后水体磷素的增加可能是由地表径流携带的面源污染物和径流引起沉积物内源磷释放所致,导致雨后总氮含量无明显变化的原因可能是反硝化作用.同时降雨径流携带的有机污染物加剧了微生物对溶解氧的消耗,有机质被分解为有机酸,这也是导致pH下降的重要原因之一.此外降雨能引起光强减弱,溶解氧和pH的降低可能与浮游藻类的光合作用受到抑制相关.Rainfall is an important way for lake nutrient input.In order to find out the characteristics of water quality changes of urban lakes before and after rainfall,Wuhan East Lake,a typical urban eutrophic lake,was selected as the research object.27 sampling points were set up in the whole lake.Surface sediment samples were collected,and 11 water quality indicators were monitored before and after rainfalls from September to October 2021.The status of nitrogen and phosphorus pollution in surface sediments and the characteristics of water quality changes in Wuhan East Lake before and after rainfall were identified.The causes of the differences in water quality before and after rainfall were analyzed by linear regression and principal component analysis.The results showed that the average contents of total nitrogen and total phosphorus in the surface sediments of Wuhan East Lake were 4065 mg/kg and 683 mg/kg,respectively,which were generally at a severe pollution level.Compared with before rain,the turbidity,total phosphorus,dissolved total phosphorus and active phosphate in the surface water increased significantly after rain(P<0.05),and dissolved oxygen,pH and nitrate nitrogen decreased significantly(P<0.05),but there was no significant difference in total nitrogen and dissolved total nitrogen(P>0.05).The increase of phosphorus in surface water after rainfall might be caused by non-point source pollutants carried by surface runoff and the release of endogenous phosphorus in sediments caused by runoff.The reason for no significant change in total nitrogen content after rain might be denitrification.At the same time,the organic pollutants carried by rainfall runoff aggravated the consumption of dissolved oxygen by microorganisms,and organic matter was decomposed into organic acids,which was also one of the important reasons for the decrease of pH.In addition,rainfall could cause the decrease of light intensity,and the decrease of dissolved oxygen and pH might be related to the inhibition of photosynthesis of phytoplankt

关 键 词：城市湖泊 东湖 表层沉积物 降雨 水质差异 

分 类 号：X824[环境科学与工程—环境工程]