长江中游典型鱼类产卵栖息水环境共性需求分析OA

The construction and operation of water conservancy hubs have changed the natural runoff process of rivers,leading to changes in the water environment of the original spawning habitats of fish and affecting the diversity of fish resources.Restoration and reconstruction of spawning habitats to meet the needs of fish spawning habitats are important measures to protect the diversity of fish resources.In order to improve the adaptability of the restored river section to the spawning habitats of various fish species,this study takes three typical fish species spawning in the middle reaches of the Yangtze River as the research object.Through factor analysis,the common demand factors and threshold ranges of their spawning habitats to the water environment are obtained.The results show that the key factors for the spawning habitat of the three typical fish species in the middle reaches of the Yangtze River are channel morphology and water temperature.The factors and thresholds for the spawning habitat of the three typical fish species are channel morphology(i.e.,curved,branching,isthmus-type,and channels with complex flow regimes),water temperature(17～25℃),flow velocity(0.50～1.75 m/s),water depth(0～22 m),and substrate quality(i.e.hard bedrock with coarse sand,gravel,cobbles and boulders).The research results can provide technical support for the artificial reconstruction of important fish spawning habitats in the middle reaches of the Yangtze River.