嘉陵江中游蓬安段鱼类群落功能多样性研究

FUNCTIONAL DIVERSITIES OF FISH COUMMUNITY IN PENG’AN SECTION OF THE MIDDLE REACH OF JIALING RIVER

研究调查了蓬安段2014—2019年洪水期(6、7和8月)和枯水期(11、12和1月)渔获物,用11项鱼类功能性状类型结合蓬安段鱼类群落结构特点来分析该江段鱼类群落功能多样性在洪、枯期上的变化及与水环境的关系。研究结果表明,(1)2014—2019年洪水期的物种丰富度指数、辛普森多样性指数、Pielou均匀度指数和香浓威纳指数均高于枯水期;(2)SIMPER分析显示,大鳍鳠Mystus macropterus、子陵吻鰕虎鱼Ctenogobius giurinus、似鳊Pseudobrama simoni、黄颡鱼Pelteobagrus fulvidraco、鳜Siniperca chuatsi、蛇Saurogobio dabryi、飘鱼Pseudolaubuca sinensis、鲫Carassius auratus、黄尾鲴Xenocypris davidi和䱗Hemiculter leucisculus是造成洪水期与枯水期鱼类群落结构变化的主要差异贡献种;(3)各年份洪水期的功能丰富度FRic、功能离散度FDiv、功能散布度FDis和二次熵指数Rao及2015、2016和2017年的功能均匀度指数FEve均显著高于枯水期(P<0.05),表明枯水期鱼群落的抵抗力稳定性和恢复力稳定性显著低于洪水期,即枯水期水生生态系统功能较脆弱;(4)鱼类群落功能多样性与水环境因子存在显著相关关系,但不同时期的功能多样性指数与环境因子相关性程度则呈现较大差异,表明功能多样性是鱼类群落结构和各水环境因子综合作用的结果。

Community functional diversity is a bridge between species and ecosystem functions,which can effectively reflect the changes of ecosystem function.In this study,the catches in flood season(June,July,August)and dry season(November,December,January)in Peng’an section from 2014 to 2019 were investigated to analyze the functional diversity of fish community and its relationship with water environment using 11 fish functional traits.The main results are as follows:(1)The Species richness index,Simpson diversity index,Pielou evenness index and Shannon wiener index in the flood period of 2014—2019 were higher than those in the dry season;(2)Simper analysis showed that 10 species,Hemibagrus macropterus Bleeker,Rhinogobius giurinus Rutther,Pseudobrama simoni Bleeker,Pelteobagrus fulvidraco Richardson,Siniperca chuatsi Basilewsky,Saurogobio dabryi Bleeker,Pseudolaubuca sinensis Bleeker,Carassius auratus Linnaeus,Xenocypris davidi Bleeker,Hemiculter leucisculus Bleeker,were the main contributors to fish community structure during flood and dry seasons.(3)The functional richness(FRic),Functional divergence(FDiv),Functional Dispersion(FDis),Quadratic entropy(Rao)and Functional evenness(FEve)in 2015,2016 and 2017 in flood season were significantly higher than those in dry season(P<0.05),indicating fragile aquatic ecosystem in dry season with low stability of resistance and resilience.(4)There was a significant correlation between the fish community functional diversity and the physical and chemical environmental factors.However,the correlation between functional diversity index and environmental factors in different periods was quite different,showing that the functional diversity was the result of the combination of fish community structure and water environmental factors.