雅鲁藏布江中游浮游植物群落优势种时空生态位  

Spatio-temporal niche of dominant species of phytoplankton community in the middle reaches of Yarlung Zangbo River

作　　者：李晓东 巢欣 刘惠秋 杨清 杨胜娴 巴桑[1,2] LI Xiaodong;CHAO Xin;LIU Huiqiu;YANG Qing;YANG Shengxian;BA Sang(Earth's Third Pole Carbon Neutralization Research Center,Tibet University,Lhasa 850000,China;Laboratory of Qinghai-Tibet Plateau Wetland and Watershed Ecosystem,College of Ecological Environment,Tibet University,Lhasa 850000,China)

机构地区：[1]西藏大学地球第三极碳中和研究中心,拉萨850000 [2]西藏大学生态环境学院青藏高原湿地与流域生态系统实验室,拉萨850000

出　　处：《生态学报》2023年第18期7746-7760,共15页Acta Ecologica Sinica

基　　金：国家自然科学基金项目(32070418);2022年中央支持地方高校发展专项资金项目(藏财预指[2022]01号)。

摘　　要：为探究雅鲁藏布江中游浮游植物群落分布格局及其优势种时空生态位特征,于2021年7月、10月对该水域进行浮游植物样品的采集和水体理化因子的测定,鉴定浮游植物物种,计算浮游植物优势种生态位宽度、生态位重叠值、生态响应速率及相对资源占有率,运用共现网络模型分析群落的种间关联性,并对浮游植物优势种与环境因子进行Pearson相关性分析。结果表明:该水域共鉴定到浮游植物644种,隶属于8门12纲25目49科152属,其中,优势种22种,优势种中硅藻占90.9%,在群落中占绝对优势;丰水期的肘状针杆藻丰度最大(74.193×10^(4)细胞/L)且出现频率最高(0.867),是丰水期绝对优势种;整体上优势种生态位宽度时间(0.833)>空间(0.254),优势种时空生态位宽度主要受空间生态位宽度的影响,空间异质性是影响该水域浮游植物优势种分布的主要因素;优势种时空二维生态位无意义重叠的种对占40.69%,优势种时空二维的生态位重叠以中、低等级为主,优势种间对时空资源需求异质性高,种间潜在竞争关系较弱;该水域枯水期浮游植物群落的网络结构紧密,群落连通性、群落复杂度和物种间生态位重叠度较丰水期高,两个水文期群落共现网络以正关联为主,种间的协同作用强于竞争作用;该水域水环境因子能驱动群落中优势类群的生态位分化,NO3-N、WT是影响雅鲁藏布江中游浮游植物群落优势种生态位分化的主要驱动因子。In order to explore the distribution pattern of phytoplankton community and the temporal and spatial niche characteristics of dominant species in the middle reaches of Yarlung Zangbo River,phytoplankton samples were collected and physical and chemical factors were measured in July and October 2021 to identify phytoplankton species.The niche width,niche overlap value,ecological response rate,and relative resource share of dominant species were calculated.The cooccurrence network model was used to analyze the interspecific associations of the community.Pearson correlation analysis was conducted between the dominant phytoplankton species and environmental factors.The results showed that a total of 644 species of phytoplankton were identified,belonging to 8 phyla,12 classes,25 orders,49 families and 152 genera.Among them,there were 22 dominant species,and 90.9%of the dominant species were diatoms,which were absolutely dominant in the community.The most abundant(74.193×10^(4)Cell/L)and the highest occurrence frequency(0.867)were found in Synedra ulna during the wet season,which was the absolutely dominant species.The temporal niche width of dominant species(0.833)was higher than that spatial niche width(0.254).The spatial and temporal niche width of the dominant species was mainly affected by the spatial niche width,and spatial heterogeneity was the main factor affecting the distribution of dominant species.The number of niche overlaps of dominant species was 40.69%,and the niche overlaps of dominant species were mainly in middle and low grade.The heterogeneity of demand for spatial and temporal resources among dominant species was high,and the potential competition between species was weak.The network structure of phytoplankton community in dry season was close,and the community connectivity,community complexity and niche overlap between species were higher than those in wet season.The community co-occurrence network of the two hydrological periods was mainly positive,and the synergistic effect between species was s

关 键 词：浮游植物 优势种 生态位 雅鲁藏布江中游 

分 类 号：Q948.1[生物学—植物学]