Comparative study on zoobenthos community characteristics in five drinking water reservoirs in Liaoning Province
To find out the community structure of zoobenthos in five drinking water reservoirs includ-ing Guanyinge Reservoir,Baishi Reservoir,Chaihe Reservoir,Qinghe Reservoir,and Tanghe Reservoir,in Liaoning Province,and to estimate the potential fishery production according to the stock of zoobenthos,then to provide scientific guidance for the stocking and fishing of water conservation fisheries,seasonal sur-veys of the five reservoirs were carried out in 2019-2020.A total of 67 taxa,belonging to 3 phyla were identified.Among them,39 species were chironomid larvae and 12 species were oligochaetes mainly Tubi-fex and Naididae.Only three species of mollusks were identified,including Radix swinhoei collected from Guanyinge Reservoir and Tanghe Reservoir,Bellamya purificata collected from Guanyinge Reservoir,and Cristaria plicata collected from Baishi Reservoir.The most species were detected in Tanghe Reservoir with 39 species,followed by 34 species in Guanyinge Reservoir,and the least in Baishi Reservoir with 23 species.The density was the highest in Baishi Reservoir with 1 546.89 ind/m2,followed by Guanyinge Res-ervoir with 658.33 ind/m2,and the lowest was Tanghe Reservoir with 481.92 ind/m2.The biomass was the highest in Baishi Reservoir with 7.76 g/m2,followed by Tanghe Reservoir with 5.68 g/m2,and the lowest was Qinghe Reservoir with 2.49 g/m2.The highest density of five reservoirs occurred in spring,summer and autumn,but the lowest values were all in summer.The biomass was higher in spring and win-ter,and lower in summer and autumn.The density and biomass of each reservoir was the highest in the still water zone.Only the highest density and biomass in Guanyinge Reservoir and biomass in Baishi Reser-voir appeared in the transition zone.The density and biomass of Guanyinge Reservoir and Chaihe Reservoir were mainly composed of oligochaetes from the river zone to the front of the dam,while the reservoir en-trance was dominated by chironomid larvae.The density and biomass of Qinghe Reservoir and Tanghe Res-ervoir were mainly composed of chironomid larvae from the reservoir entrance to the still water zone,while the front of the dam was dominated by oligochaetes.Baishi Reservoir was dominated by chironomid larvae from the reservoir entrance to transition zone,while the still water zone and the front of the dam were main-ly composed of oligochaetes.The results of clustering and MDS ordination indicated that the communities of Guanyinge,Chaihe and Qinghe reservoirs were more similar.The communities of Baishi and Tanghe reservoirs were less similar and significantly different from those of Guanyinge,Chaihe and Qinghe reser-voirs.Canonical correspondence analysis indicated that the density of zoobenthos were significantly correlat-ed with the depth of water,total nitrogen,ammonia nitrogen,dissolved organic carbon and chlorophyll-a in five reservoirs.The species and composition of zoobenthos were obviously influenced by the contents of total nitrogen and ammonia nitrogen.The contents of total nitrogen and ammonia nitrogen in Tanghe Reser-voir were the lowest,showing the most species and high dominance of chironomid larvae.The contents of total nitrogen and ammonia nitrogen in Baishi Reservoir were the highest,showing the least species and high dominance of tubificid worm.The fish production potential based on zoobenthos of Baishi Reservoir was the highest,followed by Tanghe Reservoir,and lowest in Qinghe Reservoir.Compared with previous surveys,the species numbers of five reservoirs increased,mainly due to the increase of chironomid larvae species.The trends of density and biomass were different from that of the number of species.The density and biomass of Guanyinge Reservoir decreased,while those of Qinghe and Tanghe Reservoirs increased.The density of Baishi Reservoir increased and the biomass decreased,while the density of Chaihe Reser-voir decreased and the biomass increased.The stocking and fishing of demersal fish in five water source res-ervoirs should be managed in a targeted manner according to the characteristics of zoobenthos community structure.
zoobenthoscommunity structurefish production potentialenvironmental factorsdrinking water reservoirsLiaoning Province
NETL
NSTL
万方数据
