Do alternative stable states exist in large shallow Taihu Lake,China?  

作　　者：Yan LI Yu MA Haijun WANG Hongzhu WANG Yongde CUI Shijun BIAN Miao ZHANG Mengmei LIU Yexin YU Marc SCHALLENBERG 

机构地区：[1]State Key Laboratory of Freshwater Ecology and Biotechnology,Institute of Hydrobiology,Chinese Academy of Sciences,Wuhan 430072,China [2]Institute for Ecological Research and Pollution Control of Plateau Lakes,School of Ecology and Environmental Science,Yunnan University,Kunming 650504,China [3]University of Chinese Academy of Sciences,Beijing 100049,China [4]Department of Zoology,University of Otago,PO Box 56,Dunedin 9054,New Zealand

出　　处：《Journal of Oceanology and Limnology》2023年第3期959-971,共13页海洋湖沼学报（英文）

基　　金：Supported by the National Key Research and Development Program of China(No.2021YFC3200103);the Major Science and Technology Program for Water Pollution Control and Treatment of China(No.2017ZX07302-002);the State Key Laboratory of Freshwater Ecology and Biotechnology(No.2019FBZ01);the Wuhan Science and Technology Plan Project(No.2020020602012152),the Research Project of Wuhan Municipal Construction Group Co.,Ltd.(No.wszky202014);Haijun WANG was supported by the Youth Innovation Association of Chinese Academy of Sciences as an excellent member(No.Y201859)。

摘　　要：Regime shifts from submersed macrophyte dominance to phytoplankton dominance have been widely reported in small-to medium-sized shallow lakes.However,alternative stable states in large shallow lakes(surface area>500 km^(2))remain unconfirmed.To understand the alternative stable states and the main influencing factors of submersed macrophytes in large lakes,the ecosystem states from monitoring data from 1959 to 2019 in large shallow Taihu Lake(2338 km^(2)in average depth of 2.12 m)in China were examined.Changes in submersed macrophyte coverage(C_(Mac))and phytoplankton chlorophyll a(Chl a)in the time series and their relationships with environmental factors were analyzed.During the field investigation from August 2018 to May 2019,nutrients and Chl a showed obvious heterogeneity across the lake,being generally higher in the western and northern areas and lower in the southeast area,while C_(Mac)was only observed in the eastern areas,e.g.,East Taihu Lake,Xukou Bay,and Gonghu Bay.During the long-term monitoring from 1959 to 2019 in the Central Region,Meiliang Bay,and East Taihu Lake,Chl a increased significantly in the time series.C_(Mac)varied slightly among different subareas,always at low levels(<10%)in the Central Region and Meiliang Bay but at relatively high levels in East Taihu Lake(10%–90%).Frequency distributions of response variables had no multimodality except for C_(Mac)in East Taihu Lake,with two peaks between 15%and 20%and between 55%and 60%.A dual relationship was found between Chl a and total phosphorus(TP)in the areas with and without macrophytes,while C_(Mac)showed no relationship with TP,and submersed macrophytes did not flourish in the Central Region and Meiliang Bay even when TP was at very low levels(≈10 mg/m3).Taihu Lake had similar algal turbidity(TurbAlg)as small-to mediumsized lakes but generally presented with higher values of nonalgal turbidity(TurbNonAlg),as did their contribution to total turbidity as a percentage.This study suggested that large shallow Taihu Lake may have no alterna

关 键 词：alternative stable state submersed macrophyte PHYTOPLANKTON Taihu Lake large shallow lake 

分 类 号：P343.3[天文地球—水文科学] Q948.8[天文地球—地球物理学]