Study Of The Community Structure Of Macrozoobenthos And Its Relationship With Environmental Factors Of Different Types Of Water Bodies In Shanghai

At present,with the rapid development of urbanization process,the water pollution in Shanghai intensified,the eutrophication of water is becoming more and more serious,and the creatures in the water are tragically killed.In recent decades,with the implementation of a series of important ecological evaluation and protection projects in Shanghai,the research on the relationship between biology and environment in water has also been carried out.The studys rely on these projects "Important rivers and lakes health assessment-Huangpu River","Dianshan Lake water eutrophication and cyanobacteria control technology" and "Shanghai eco-river assessment system",and study the community structure of macrobenthic fauna and its relationship with environmental factors of Shanghai Dianshan Lake,Huangpu River and 22 rivers.Firstly,the distribution of macrozoobenthos,physical and chemical environmental condition and historical data of Dianshan Lake,Huangpu River and 22 rivers in Shanghai were investigated in detail.Then,the main environmental factors affecting benthic fauna were analyzed.This study has the following key aspects:There was a total of 109 species of macrobenthic fauna attribute 8 classes and 69 generas were obtained,which 3 classes 19 generas 23 species belonging to annelid,3 classes 16 generas 23 species belonging to mollusk,2 classes 34 generas 63 species belonging to arthropod.1.The 48 species of macrozoobenthos collected from the Dianshan Lake belonging to 3 phylums 7 classes 35 generas.which 3 classes 8 generas 9 species belonging to annelid,2 classes 10 generas 12 species belonging to mollusk,2 classes 17 generas 27 species belonging to arthropod.The dominance species were,Corbicula fluminea Tylorrhynchus heterochaetus sp.,Propsilocerus akamusi,Corophium volutator,Limnodrilus hoffmeisteri,Propsilocerus taihuensis,Nephtys oligobranchia,Laonome triangularis.The average density of macrozoobenthos in Dianshan Lake was 351.7ind./m2 and the average biomass was 115.21g/m2 during the year of 2014 and 2015.Pearson correlation analysis showed that the density of Corbicula corniculatus was negatively correlated with the pH.The density of the Tylorrhynchus heterochaetus sp.was significantly negatively correlated with CODMn and pH,and a significant positive correlation with DO.There was a significant negative correlation between the density and pH of the Propsilocerus akamusi,a significant negative correlation with the T,and a significant positive correlation with DO.There was a significant negative correlation between the density and pH of Corophium volutator.There was a significant negative correlation between the density and the pH of Limnodrilus hoffmeisteri,and a significant positive correlation with the TP and T.The density of Propsilocerus taihuensis was negatively correlated with pH.The density of Nephtys oligobranchia has a significant negative correlation with DO,and a significant positive correlation with the CODMn and pH.The correlation between density and environmental factors of Laonome triangularis was not significant.2.There are a total of 29 species of macrobenthic fauna attribute 3 phylums 7 classes and 25 generas were obtained from the Huangpu River survey,which 2 classes 5 species belonging to mollusk,3 classes 14 species belonging to annelid,2 classes10 species belonging to arthropod.The average density was 1712.96 ind./m2 and the average biomass was 16.72 g/m2.The dominant species were Limnodrilus hoffmeisteri,Limnodrilus grandisetosus,Corbicula fluminea and Corbicula nitens.The Pearson correlation analysis showed that,in 2013,the density of Limnodrilus hoffmeisteri was significantly positive correlation with pH.The density of Corbicula fluminea was significantly negative correlation with TN.The density of Limnodrilus grandisetosus was significantly negative correlated with pH and Tur.The density of Branchiura sowerbyi and Crandidierella japonica has nothing correlation with environmental factors.And in 2014,the density of Limnodrilus hoffmeisteri was significantly negative correlation with T.The density of Corbicula fluminea was significantly negative correlation with TP.The density of Nephtys sp.was significantly negative correlation with T.The density of Nereis sp.was significantly negative correlation with Sal,very significantly negative correlation with Cond,was significantly positive correlation with T and NH4+-N.The density of Limnodrilus grandisetosu was very significantly negative correlation with T,significantly positive correlation with Sal and TP,very significantly positive correlation with Cond.The density of Laonome triangularis,Branchiura sowerbyi,Corbicula nitens and Crandidierella japonica was not significantly correlation with environmental factors.3.There are a total of 87 species of macrozoobenthos belonging to 3 phylums 8 classes 56 generas were obtained from five types of river in Shanghai,there are 3 classes 13 genera 19 species belonging to the mollusks,3 classes 14 genera18 species belonging to annelid.2 classes 19 genera 50 species belonging to arthropod.The average density was 295.1ind./m2,the biomass was 131.6g/m2.The dominant species were Limnodrilus hoffmeisteri,Chironomus flaviplumus,Bellamya purificata,Bellamya aeruginosa.The Pearson correlation analysis showed that the density of common species of macrobenthic fauna in different types of rivers in Shanghai was mainly correlated with total phosphorus and chlorophyll-a.The results showed that the density of Limnodrilus hoffmeisteri was significantly positive correlation with total phosphorus and chlorophyll a,and the density of Chironomus flaviplumus was positively correlated with total phosphorus and had a significant positive correlation with chlorophyll a.The density of Limnoperna lacustris was significantly negative correlation with transparency.There was a significant negative correlation between the density and the transparency of Corophium volutator,and the density of Tanypus punctipennis was significantly positively correlated with the chlorophyll-a,and significantly positive correlation with total phosphorus.the densityof Tanypus chinensis was significant positive with permanganate index,the density of Propsilocerus akamusiwas significant positive correlation with transparency and ammonia nitrogen and very significant positive correlation with total nitrogen.