三十年来长江中下游湖泊富营养化状况变迁及其影响因素  

Changing characteristics and driving factors of trophic state of lakes in the middle and lower reaches of Yangtze River in the past 30 years

作　　者：朱广伟[1] 许海[1] 朱梦圆[1] 邹伟[1] 国超旋 季鹏飞 笪文怡 周永强[1] 张运林[1] 秦伯强[1] ZHU Guangwei;XU Hai;ZHU Mengyuan;ZOU Wei;GUO Chaoxuan;JI Pengfei;DA Wenyi;ZHOU Yongqiang;ZHANG Yunlin;QIN Boqiang(Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, P. R. China;School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, P. R. China;China West Normal University, College of Environmental Science and Engineering, Nanchong 637002, P. R. China)

机构地区：[1]中国科学院南京地理与湖泊研究所湖泊与环境国家重点实验室太湖湖泊生态系统研究站,南京210008 [2]江南大学环境与土木工程学院,无锡214122 [3]西华师范大学环境科学与工程学院,南充637002

出　　处：《湖泊科学》2019年第6期1510-1524,共15页Journal of Lake Sciences

基　　金：中国科学院战略性先导科技专项(A类)(XDA23040201);中国科学院重点部署项目(ZDRW-ZS-2017-3-4);国家自然科学基金项目(41671494,41830757)联合资助

摘　　要：为弄清长江中下游通江/历史通江湖泊富营养化现状、成因及修复策略,对该区域27个大型湖泊和水库开展了4个季度的水质调查,并结合部分湖泊1988-1992年及2008年两个时段富营养化调查成果,分析近30年来长江中下游地区大型湖泊富营养化关键指标变化的特征及其驱动因素.结果表明,目前该区域绝大多数湖泊处于富营养水平,较1980s有明显加重,浮游植物叶绿素a及总磷是最主要的营养状态指数贡献因子;湖泊的富营养化状况与湖泊的江湖连通状况、换水周期等流动性状况、渔业养殖及管理、流域纳污、治理强度等人类活动方式和强度密切相关;与历史调查结果相比,氮、磷的增幅相对较小,而有机质污染程度明显加重、浮游植物叶绿素a浓度大幅增高,表明营养盐之外的其他因素,如水文节律的变化、江湖阻隔、不合理的渔业养殖活动等,对该区域湖泊的富营养化问题加剧、浮游植物生产力增高起到更为重要的作用.因此,从治理途径和策略上来看,增加湖泊的流通性、恢复部分湖泊的自然水文波动节律、优化湖泊渔业管理、提升湖泊流域营养盐的有效截留能力、实施湖泊生态修复工程是控制长江中下游湖泊富营养化、提升区域湖泊生态质量的关键.To understand the current eutrophication status, main drivers of eutrophication and restoration strategy of Yangtze-connected or Yangtze-isolated lakes (historically connected to the Yangtze River but isolated by artificial dikes currently), the trophic parameters and main water quality variables were surveyed seasonally in 27 large lakes and reservoirs of this region during 2017 to 2018. In addition, the temporal eutrophication dynamics and associated driving mechanisms of these lakes over the past 30 years were analyzed based on the historical data of these lakes (investigated during 1988 to 1992 and 2008). Our results showed that most of the lakes in the middle and lower reaches of Yangtze River were eutrophic now, and significantly worse than the status of 1988 to 1992, mainly contributed by chlorophyll-a of phytoplankton and total phosphorus. Human activities, including changes of water retention time (primarily depend on the lake-Yangtze connection condition), fishery activities, catchment pollution condition, and lake restoration are decisive factors in shaping the eutrophication status of these lakes. Comparing with the historical records, phytoplankton chlorophyll-a and associated organic matter concentrations are increased drastically, while nutrients (e.g., total phosphorus and nitrogen) experienced relatively small increase, yet. Therefore, it is suggested that the non-nutrients factors were the major causes which strengthen the eutrophication risk. From the perspective of restoration strategies of lakes in the middle and lower reaches of Yangtze River, it is crucial that rebuild the hydrological connectivity, restore natural water level fluctuation, optimize the fishery management and enhance the catchment nutrient abatement ability and applying the in-lake restoration engineering.

关 键 词：长江中下游平原 浅水湖泊 富营养化 江湖阻隔 生态渔业 网围养殖 

分 类 号：X524[环境科学与工程—环境工程]