三峡水库中小洪水调度对支流库湾浮游植物的影响及机制  

Impact and Mechanism of Medium and Small Flood Regulation in the Three Gorges Reservoir on the Phytoplankton in Tributary Bays

作　　者：黎睿[1,2,3] 汤显强 刘新波[3] 陈文重 王丹阳 任玉峰 LI Rui;TANG Xian-qiang;LIU Xin-bo;CHEN Wen-zhong;WANG Dan-yang;REN Yu-feng(Basin Water Environmental Research Department,Changjiang River Scientific Research Institute,Changjiang Water Resources Commission,Wuhan 430010,China;Key Laboratory of Basin Water Resource and Eco-Environmental Science in Hubei Province,Changjiang Water Resources Commission,Wuhan 430010,China;Hubei Key Laboratory of Intelligent Yangtze and Hydroelectric Science,China Yangtze Power Co.,Ltd.,Yichang 443000,China;Three Gorges Hydrology and Water Ministry of Water Resource Survey Bureau,Changjiang Water Resources Commission,Yichang 443000,China)

机构地区：[1]长江水利委员会长江科学院流域水环境研究所,武汉430010 [2]长江水利委员会长江科学院流域水资源与生态环境科学湖北省重点实验室,武汉430010 [3]中国长江电力股份有限公司智慧长江与水电科学湖北省重点实验室,宜昌443000 [4]长江水利委员会水文局长江三峡水文水资源勘测局,宜昌443000

出　　处：《环境科学》2024年第9期5308-5317,共10页Environmental Science

基　　金：中央级公益性科研院所基本科研业务费专项(CKSF2021444/SH,CKSF2023163/SH);国家自然科学基金项目(41907401);智慧长江与水电科学湖北省重点实验室开放基金项目(ZH2102001)。

摘　　要：中小洪水调度已成为三峡水库汛期的主要调度方式,为研究三峡水库支流库湾浮游植物对中小洪水调度的响应,以三峡水库典型富营养化支流香溪河为对象,调查监测了2020~2021年汛期干支流浮游植物、营养盐及水体理化参数的时空分布特征,分析了支流库湾浮游植物对中小洪水调度的响应特征.结果表明,中小洪水调度期间,香溪河库湾水体叶绿素a(Chl-a)随着坝前水位升高而降低,而在汛末蓄水期,Chl-a浓度再次升高.中小洪水调度期间,香溪河浮游植物以绿藻门和硅藻门为主,其群落组成随中小洪水调度而改变,当水位变幅增大时,以硅藻为主,当水位变幅较小时,以蓝、绿藻为主.Chl-a浓度对库湾水体TN浓度变化更为敏感,当库湾水体流速>0.25 m·s^(−1),或者悬浮泥沙浓度>10 mg·L^(−1)时,水体Chl-a浓度受到抑制.2010年以后,香溪河库湾典型水华暴发时间转变为以汛期为主,非汛期水华仅有2次,需要进一步关注汛期库湾藻类对中小洪水调度的响应.The regulation of small-and medium-sized floods(RSMF)has become the main mode of regulation in the flood season of the Three Gorges Reservoir(TGR).To study the response of phytoplankton in the tributary bays of the TGR to the RSMF,a typical eutrophic tributary of the TGR,Xiangxi River,was investigated for the spatiotemporal distribution characteristics of phytoplankton and nutrients in the main and tributary streams from 2020 to 2021.The response characteristics of phytoplankton in the tributary bays to the RSMF were analyzed.The results indicated that during the RSMF,the chlorophyll a(Chl-a)in the water body of the Xiangxi River decreased with the increase in the water level in front of the dam,whereas during the reservoir impounding at the end of flood season,the concentration of Chl-a increased again.During the RSMF,the Chlorophyta and Diatoma were the main communities of planktonic algae in the Xiangxi River.The phytoplankton community changed with the RSMF.When the water level fluctuation increased,diatoms were the main species,whereas when the water level fluctuation was small,blue and green algae were the main species.The concentration of Chl-a was more sensitive to changes in TN concentration.When the flow velocity was>0.25 m·s^(−1)or the suspended sediment content was>10 mg·L^(−1),the concentration of Chl-a in the water was inhibited.After 2010,the typical outbreak time of algal blooms in the Xiangxi River Reservoir Bay shifted to the flood season,with only two non-flood season algal blooms.Further attention needs to be paid to the response of algal blooms in the reservoir to small-and medium-sized flood control during the flood season.

关 键 词：三峡水库 中小洪水调度 浮游植物 悬浮泥沙 水动力条件 

分 类 号：X171[环境科学与工程—环境科学]