摘要
梯级水电开发在提升水资源利用效率的同时,也改变了水生态系统的结构和功能.浮游植物作为河流生态系统的初级生产者,对环境变化极为敏感.现有研究多关注梯级水库对浮游植物时空变化的描述,鲜有从群落构建机制角度进行研究.本研究以黄河上游龙羊峡-刘家峡河段6座超大型梯级水库为研究对象,在枯水期和丰水期开展了水环境与浮游植物的采样调查;解析不同季节浮游植物群落结构特征,利用中性群落模型探讨梯级水库对浮游植物群落构建机制的影响.结果表明:(1)枯水期浮游植物以硅藻门为优势种群,而丰水期蓝藻门和绿藻门的优势种群显著增加;(2)在龙羊峡和刘家峡水库,藻密度和生物量均呈现出库区、上游河道、坝下河道依次递减的趋势;(3)中性群落模型的拟合度(R^(2))和校正随机率均低于0.5,表明确定性过程在浮游植物群落构建中占主导地位;(4)驱动浮游植物群落结构变化的主要因素包括水温(7.62%)、水力停留时间(6.52%)、总氮(5.75%)、海拔(4.97%)、硝态氮(4.73%)以及浮游动物的下行调控作用(4.70%).本研究深化了对梯级水库运行影响下浮游植物群落演变规律的认识,为高山河流梯级开发中的水生态系统保护与修复提供了科学依据.
Cascade hydropower development promotes the efficient utilization of water resources and alters the structure and function of aquatic ecosystems.As the primary producers in riverine ecosystems,phytoplankton is highly sensitive to environmental changes.Studies conducted so far have predominantly focused on the spatial and temporal dynamics of phytoplankton in cascade reservoirs,giving limited attention to mechanisms shaping community structure.This study investigated six super-large cascade reservoirs along the Longyangxia to Liujiaxia section of the upper Yellow River.Sampling surveys of the aquatic environment and phytoplankton were conducted during the dry and wet seasons.The study involved analyzing the seasonal characteristics of phytoplankton community structure and exploring the effects of cascade reservoirs on community assembly mechanisms using a neutral community model.The results revealed the following.During the dry season,phytoplankton was dominated by Bacillariophyta,whereas during the wet season,the proportion of Cyanophyta and Chlorophyta significantly increased.In the Longyangxia and Liujiaxia reservoirs,algal density and biomass were highest in the reservoir area,followed by the upstream river section,and were least in the downstream river section.The neutral community model had a goodness-of-fit(R^(2))and a corrected stochastic ratio below 0.5,indicating that deterministic processes dominated the phytoplankton community assembly.Key environmental factors driving phytoplankton community structure changes included water temperature(7.62%),HRT(6.52%),TN(5.75%),altitude(4.97%),NO 3-N(4.73%),and the downstream effect of zooplankton(4.70%).This study enhances understanding of the evolution patterns of phytoplankton communities under the influence of cascade reservoir operations,providing a scientific basis for the protection and restoration of aquatic ecosystems in the cascade development of mountain rivers.
作者
罗其勇
朱林宇
祖志刚
陈科冰
王袈
李代魁
易雨君
LUO QiYong;ZHU LinYu;ZU ZhiGang;CHEN KeBing;WANG Jia;LI DaiKui;YI YuJun(State Key Laboratory of Regional Environment and Sustainability,School of Environment,Beijing Normal University,Beijing 100875,China;School of Biological and Chemical Engineering,Guangxi University of Science and Technology,Liuzhou 545005,China;Ministry of Education Key Laboratory of Water and Sediment Science,Beijing Normal University,Beijing 100875,China;School of Civil Engineering,Yantai University,Yantai 264005,China)
出处
《中国科学:技术科学》
北大核心
2025年第7期1207-1221,共15页
Scientia Sinica(Technologica)
基金
国家自然科学基金联合基金项目(批准号:U2243236)
国家自然科学基金创新群体项目(批准号:52221003)
国家杰出青年科学基金项目(批准号:52025092)资助。
关键词
浮游植物
中性群落模型
群落构建
梯级水库
黄河上游
phytoplankton community
neutral community model
community assembly
cascade reservoir
the upper Yellow River
