富营养化和渔业生产对保安湖沉水植物群落演替的影响  

IMPACTS OF EUTROPHICATION AND FISHERY PRODUCTION ON THE SUCCESSION OF SUBMERGED MACROPHYTES IN BAO'AN LAKE

作　　者：刘孟梅 李艳 李为[1] 屈霄 申东方 刘佳豪 乔瑞婷 赵永晶[1] 熊芳园 王洪铸[1] LIU Meng-Mei;LI Yan;LI Wei;QU Xiao;SHEN Dong-Fang;LIU Jia-Hao;QIAO Rui-Ting;ZHAO Yong-Jing;XIONG Fang-Yuan;WANG Hong-Zhu(State Key Laboratory of Freshwater Ecology and Biotechnology,Institute of Hydrobiology,Chinese Academy of Sciences,Wuhan 430072,China;University of Chinese Academy of Sciences,Beijing 100049,China;College of Fisheries and Life Science,Dalian Ocean University,Dalian 116023,China)

机构地区：[1]中国科学院水生生物研究所淡水生态与生物技术国家重点实验室,武汉430072 [2]中国科学院大学,北京100049 [3]大连海洋大学水产与生命学院,大连116023

出　　处：《水生生物学报》2023年第11期1769-1777,I0001,I0002,共11页Acta Hydrobiologica Sinica

基　　金：湖北省重点研发计划(YFXM2022000294);中国科学院水生生物研究所“生态文明”特色研究所服务性项目“阻隔湖泊鱼类群落结构调整及生态系统功能优化研究”(Y85Z0511);武汉市科技计划项目(2020020602012152);武汉市政建设集团有限公司科研项目(wszky202014);淡水生态与生物技术国家重点实验室课题(2019FBZ01)资助。

摘　　要：为了解其沉水植物群落特征及富营养化和渔业生产对植物群落演替的影响,利用长期监测数据分析了保安湖近40年来沉水植物、水质及渔业资源的变化,结果表明:(1)1970s—1980s,常见沉水植物约10种,以穗状狐尾藻、微齿眼子菜和菹草为主,生物量较高(年均值,1005—5954 g/m^(2));1990s常见沉水植物约7种,以微齿眼子菜和菹草为主,生物量有所下降(209—877 g/m^(2));2000s—2010s,沉水植物群落结构趋于简单化,菹草演替为单优种群,生物量变化较大(1—1478 g/m^(2));2021年以来,沉水植物基本消失;(2)1980s至今保安湖氮磷营养水平呈持续上升趋势;1980s—1990s水体总磷含量(TP)约0.03 mg/L,远低于浅水湖泊草藻稳态转换阈值(0.08—0.12 mg/L),此时富营养化对沉水植物的影响不大;2000s水体营养含量快速上升,2003年TP为0.07 mg/L,接近草藻稳态转换阈值,此后一直维持在较高水平,是导致沉水植物群落衰退的重要原因之一;(3)1980s—1990s以放养草鱼和河蟹为主,鱼产量为(62—101)×10^(4)kg,草鱼放养量约1.5×10^(4)kg,河蟹产量约3.0×10^(4)kg,草鱼和河蟹对植物的摄食是导致这一时期沉水植物生物量下降的主要原因;2000s鱼产量大增,最高达500×10^(4)kg,放养鱼类以滤食性的鲢鳙为主,还有大量河蟹,对沉水植物的生存与发展仍存在不利影响;自2018年禁渔后,渔业资源量大幅降低,仅放养鲢鳙,对沉水植物的直接影响较小。以上结果表明近40年保安湖沉水植物生物多样性显著下降、群落结构趋于简单化;1980s—1990s,过度发展渔业(草鱼牧食)是影响沉水植物群落演替的关键因素,2000s植物群落演替受富营养化和过度养殖的双重胁迫,近年来富营养化是影响植物群落的关键因素。研究以保安湖为例,阐述了富营养化和渔业生产对阻隔湖泊沉水植物群落演替的影响,可为长江中下游类似浅水湖泊的管理工作提供理论依据。In recent decades,submerged macrophytes recession has become a prevalent environmental problem in shallow lakes in the middle and lower reaches of the Yangtze River affected by human disturbance and other factors.Bao'an Lake is located in the middle reaches of the Yangtze River.To understand the characteristics of submerged macrophytes community and the impacts of eutrophication and fishery production on the succession of macrophytes community,we analyzed the changes of the submerged macrophytes community,water quality and fishery resources in Bao'an Lake in the recent 40 years.The data were collected from our long-term monitoring,literature and the local lake management department.The results showed that:(1) During 1970s—1980s,there were about 10 common species of submerged macrophytes,mainly including Myriophyllum spicatum,Potamogeton maackianus and Potamogeton crispus,the annual average biomass was 1005—5954 g/m~2.In 1990s,there were about 7 common species of submerged macrophytes,mainly Potamogeton maackianus and Potamogeton crispus,and the biomass decreased to 209—877 g/m~2.During 2000s—2010s,the structure of submerged macrophytes was simplified,and Potamogeton crispus became the monodominant species,and the biomass changed greatly,fluctuated between 1 and 1478 g/m~2.Since 2021,submerged macrophytes have basically disappeared.(2) From the 1980s to now,the nutrients content of Bao'an Lake exhibited an upward trend.Total phosphorus content(TP) during 1980s—1990s was about 0.03 mg/L,which was much lower than the regime shift threshold in shallow lakes.Eutrophication has little effect on submerged macrophytes at this time.In the 21st century,the nutrients content in lake water increased rapidly.In 2003,TP was 0.07 mg/L,which was close to the regime shift threshold.Since then,it was maintained at a relatively high level,which was one of the important reasons resulting in the decline of submerged macrophytes.(3) During 1980s—1990s,Ctenopharyngodon idellus and Eriocheir japonica sinensis were mainly sto

关 键 词：阻隔湖泊 沉水植物 菹草 群落演替 保安湖 

分 类 号：S932.8[农业科学—渔业资源]