Effect On Community Structure Of Crustacean Zooplankton Of The Process Of Water Ecological Restoration

The pre-reservoir technology,joint eco-remediation technology by bio-rope and wetland plants were used for the ecological engineering of the Qinshui River in Wuxi city,Jiangsu province.In order to study the relationship between water environment factor and planktonic crustaceans community structure,the influence of planktonic crustaceans community structure with the change of water quality and its significance in ecology at the ecological restoration process,the community structure of crustacean zooplankton in the Qinshui River was investigated from June to December 2014.In this study,we have monitored the transformation of crustacean zooplankton during ecological restoration of Qinshui River,including the composition of crustacean zooplankton species,community structures,and the relationships between them and environmental factors.Futhurmore,impacts of pre-reservoir and bio-rope wetlands bioremediation technology on crustacean zooplankton community have been analyzed comparatively.And finally we evaluated the effectiveness of ecological restoration of Quishui River.The main conclusions are the following:1.The ecological restoration of Qinshui River is helpful for decressing contents of nitrogen and phosphorus nutrients and improving water quality.Contents of N and P in ecological restoration area were lower than those in pre-reservoir area,including 40% decline of total nitrogen(TN),57.14% decline of total phosphorus(TP).In addition,water turbidity transparency have been well improved by 74.15% decline and 55.14% increase,respectively.2.In the process of ecological restoration.A total of 24 species were identified,including cladocerans by 11 taxa(10 genera)and Copepods by 13 taxa(11 genera).Creiodaphnia cornuta,Bosmina coregoni,Limnoithona sinensis,Microcylops javanus and Mesocyclops leuckarti were dominant species during the study period.The maximum density and biomass(1005.00ind/L?8617.1?g/L)of crustacean zooplankton were recorded in August,while the minimum(1.80ind/L?11.4?g/L)were recorded in November and December.After ecological restoration,the biomass of crustacean zooplankton increased from 892.6 ?g/L(in pre-reservoir)to 1018.5?g/L(in ecological restoration area).3.Species,density and biomass of crustacean zooplankton in Qinshui River have been restored well according to the improvement of water quality.The number of Crustacean zo oplankton species in prereservoir area has been rised from 13 to 16,and which were not exist before were occurred.Biodiversity of crustacean zooplankton in ecological restoration area was higher than that in pre-reservoir area.Ecological restoration measures,like aquatic plants reconstruction and bio-rope resettlement,etc.,have directly or indirectly affected the structure of crustacean zooplankton community and increased the biodiversity of it.4.Results of Pearson correlation analysis showed that abundance of crustacean zooplankton was positively correlated to TP,chl-a and T.This suggested that ecological restoration measures was helpful for improving water quility and rising biodiversity of crustacean zooplankton community,which was crucial for ecological restortion of the whole Quishui River.So it proved that an ecological engineering including pre-reservoir technology,joint bio-remediation technology by bio-rope and wetland plants could reduce nutrients effectively and improved the crustacean zooplankton community structure.Therefore,this ecological engineering should be promoted in similar river eco-remediation projects in future.