Analysis of Fish Community Distribution and Its Relationship with Environmental Factors in Different Freshwater Eco-Regions of Taizi River Basin
WANG Yuntao;ZHANG Yuan;GAO Xin;MA Shuqin;YIN Xuwang;DING Sen;Liaoning Provincial Key Laboratory for Hydrobiology,College of Fisheries and Life Science,Dalian Ocean University;State Key Laboratory of Environmental Criteria and Risk Assessment,Chinese Research Academy of Environmental Sciences;College of Fisheries,Huazhong Agricultural University;
An eco-region includes similar structures and functions in adjacent regions. In order to make effective conservation strategies,it is vital to identify the relationship between aquatic organisms and environmental factors. A total of 53 sites were selected in the main channel of the Taizi River Basin in August 2010. The correlation between fish community structure and environmental factors in different eco-regions was investigated. Additionally,the fish index of biological index( F-IBI) was used to assess the river health condition,and key environmental factors affecting the fish community in each eco-region were screened. The results showed that three ecoregions( Ι,Ⅱ and Ⅲ) were defined with F-IBI methods,and named as eco-region Ι( mountainous in the upstream area),which was in healthy condition, eco-region Ⅱ( hills in the midstream area),which was in fair condition and eco-region Ⅲ( plain region in the downstream area), which was in poorcondition. With comparisons of environmental factors under different health conditions( good condition with F-IBI 50. 03 vs. poor condition with F-IBI 37. 06),there were different environmental factors showing a significant discrepancy in each eco-region. The key environmental factors were ρ( TN) in eco-region Ι( P 0. 05),percent forest( P 0. 05) in eco-region Ⅱ,and altitude and ρ( TDS)( P 0. 05) eco-region Ⅲ. Based on the data of fish and environmental factors,the correlation between community structure and the environment was analyzed by canonical correspondence analysis( CCA). The results showed that different eco-regions had different significant environmental factors which affected the distribution characteristic of fish species and community. Average velocity( F = 2. 75,P = 0. 005) played the key role for eco-region Ι,percent forest( F = 2. 65,P = 0. 003) for eco-region Ⅱ,and the chemical pollutants which affected the water quality in eco-region Ⅲ,such as the ρ( COD_(Cr))( F = 3. 83,P = 0. 001),ρ( TP)( F = 3. 46,P = 0. 001) and pH( F = 2. 90,P = 0. 002). To make more effective conservation strategies for fish biodiversity,it is indispensable to identify the key environmental factors which affect the fish community. Therefore,the special environmental strategies of different eco-regions should be considered during the fish protection planning.
【Fund】： 国家水体污染控制与治理科技重大专项(2012ZX07501-001-04);; 国家自然科学基金项目(41401066);; 中央高校基本科研业务专项(2662015QD004)
【CateGory Index】： S931.1;X174
【CateGory Index】： S931.1;X174