高邮湖浮游植物优势种生态位及种间联结季节分析OA

Identification of dominant species is a good way to begin a study of the response of a biologi-cal community to their environment,and exploring differences in the ecological niches of dominant spe-cies and their interconnections is important for analyzing community change mechanisms.In this study,Gaoyou Lake in Jiangsu Province was selected for research,and we investigated the ecological niche and interspecies connectivity of dominant phytoplankton species in Gaoyou Lake across seasons.We aimed to reveal seasonal trends and adaptation mechanisms of the dominant phytoplankton categories and provide scientific and practical references for protecting water quality,controlling eutrophication,and restoring Gaoyou Lake.From April 2020 to December 2021,a field investigation of phytoplankton and water quality was carried out at 13 sampling sites in Gaoyou Lake.Ecological niche width and the niche overlap index were used to measure the distributions of dominant phytoplankton species in different seasons,and the variance ratio,chi-square,and other statistical methods were used to evaluate the interspecific associations of dominant phytoplankton species.A total of 14 dominant phytoplankton species were identified in the four monitoring seasons in Gaoyou Lake,with Cyclotella stelligera,Pseudanabaena lim-netica,Aphanizomenon flos-aquae,and Chroomonas acuta being primary.The ecological niche width of the dominant species ranged from 0.167 to 0.880,and seasonal differences were significant.The range of ecological niche overlap was 0.11-0.97,high in summer and low in winter.The results of the variance ra-tio showed significant positive associations among pairs of dominant species.Chi-square values showed that the ecosystem structure of Gaoyou Lake was relatively mature in spring and autumn,with ecological requirements varying among phytoplankton species.Competition for resources and space was not intense,and the community remained in a temporarily stable state.Interspecific associations among dominant phy-toplankton species in Gaoyou Lake were relatively weak,with relatively independent species distributions and a comparatively simple community structure.Overall,the phytoplankton community structure in Gaoyou Lake exhibited a pattern across seasons(spring to winter)of stable-unstable-stable-unstable.