Study On The Characters Of Attached Algae Community Structureand Its Indication For Environment Of Rivers In Shanghai

24 rivers of Shanghai were samplinged and surveyed from 2015 from December 2015 to January 2016.58 sampling stations were provided to monitor water quality and collected algae.Some water quality data were meashured by field job and laboratory analysis.By identifying the periphyton that include epipelic algae and artificial substrate attached algae to collect species data.Under the influence of physical and chemical factors,the changes of community structure of algae and its response to water quality were studied by means of redundancy analysis(RDA).The water quality was evaluated by the indication of the algae species,the diatom diatomic index,the diatomace index(GDI),the motion diatom index,and the diatomaceous index.There were some differences in the nutrient of each river,even if the same river,the nutrient of each point is different too.The trophic state index(TSI)were calculated by Chla TN,TP,COD and SD.PLS1?XFS2?XFS3 belongs to mesotropher;There were 25 samplings stations are light eutropher;There were 25 samplings stations belong to middle eutropher include LJS1?LJS2?LJS3?XZS2?DZHS3;XGS2?GSS3 belongs to hyper eutropher.The species composition,biomass,community diversity of benthic algae were studied in 41 sampling station in Shanghai.Three hundred and forty seven taxa of epipelic algae belonging to eighty two genera of 4 phylum were identified,The numbers of species of each phylum had a big difference.There were 34 species of Chlorophyta accounting for 9.8 percent of the total species.There were 24 species of Cyanophyta accounting for 6.92 percent of the total species.There were 40 species of Euglenophyta accounting for 11.53 percent of the total species.There were 249 species of Bacillariophyta accounting for 71.76 percent of the total species.The highest station was GSS3,with 100 species.The dominant species were Oscillatoria okni,Oscillatoria subbrevis f.minor,Oscillatoria subbrevis,Oscillatoria neglecta,Cyclostephanos tholiformis,Cocconeis placentula,Navicula rostellata,Melosira granulata,Bacillaria paradoxa,Nitzchia palea,Cyclotella meneghiniana.The algae density and biomass among 41 sampling sites were different.The algae density in sites XLS3 were highest,and the lowest density of algae appeared LTS1.The change of algae biomass were consistent with the change of algae density.The highest aleae biomass appered XLS3,and the lowest algae biomass appeared LTS1.The niche of breadths of epipelic diatom had compared among samplings sites.And diatoms that having dramatic niche breadths variations could be observed as eutrophy indictor: Bacillaria paradoxa,Surirella angusta,Navicula cryptocephala,Navicula rhynchocephala,Aulacoseira alpigena,Navicula gregaria,Sellaphora pupula,Melosira granulata,Cocconeis placentula,Achnanthedium minutis,Navicula vecens,Surirella minuta,Nitzschia acicularis,Nitzschia filiformis,Nitzchia gracilis,Gyrosigma acuminatum,Gomphonema parvulum,Cyclotella meneghiniana,Nitzchia palea.These diatom species largely belong to ?-semi-spebic indicator species and ?-semi-spebic indicator species,which indictated that water quality.The result show that many ditoms that mentioned above largely appered in ZX,PL,WP,TJ and DZ.That means the nutrition of these rivers were higher than others.The GDI of 41 samplings were differens.The highest GDI appered XFS2.And in the YGS1,XGS2,MJS7,LJS1 the GDI were lower than other sampling stations.The percentage of motile diatom ranged from 93.3%~0.15%.Bacillariophyta divided number ranged from 3.216~0.004.Analyzing the epipelic diatoms by the method of RDA indicated that species such as Bacillaria paradoxa,Nitzschia flexa,Navicula germainii and Achnanthedium minutis were negative correlated with TN,TP and TOC,the majority that left were positive correlated with TN,TP and TOC.The species composition,biomass,community diversity of attached algae were studied in 51 sampling station in Shanghai.Three hundred and twenty-five taxa of artificial subustrates attached algae belonging to one handred and one genera of eight phylum were identified,The numbers of species of each phylum have a big difference.There were 71 species of Chlorophyt,1 species of Euglenophyta,38 species of Cyanophyta,1 species of Chrysophyta,2 species of Pyrrophyta,2 species of xanthophyte,119 species of Bacillariophyta,1 species of Cryptophyta,accounting for21.85%,5.23%,11.69%,0.31%,0.62%,0.62%,59.38%,0.1% in total species composition respectively.The highest station was GSS3,with 100 species.The dominant species were Lyngbya sp2,Bacillaria paradoxa,Cymbella pusilla,Cyclotella meneghiniana,Gomphonema pala,Gomphonema parvulum,Synedra delicatissima,Melosira granulata,Synedra ulna,Nitzchia palea,Cyclotella meneghiniana,Synedra ulna var.danica,Naicula vecens.The artificial subustrates attached algae density and biomass among 51 sampling stations were different.The algae density in sampling stations LJS2 were highest,and the lowest algae density appeared WPS3.Biomass and community diversity had a difference.the highest aleae biomass appered GSS2,and the lowest algae biomass appeared DSATS3.The niche of breadths of epipelic diatom had compared among sampling stations.And diatoms that having dramatic niche breadths variations could be observed as eutrophy indictor: Synedra ulna,Achnanthedium minutis,Melosira varians,Cyclotella meneghiniana,Aulacoseira alpigena,Nitzschia acicularis,Synedra delicatissima,Nitzschia filiformis,Gomphonema lippertii,Surirella minuta,Navicula gregaria,Encyonema minutum,Melosira granulate,Navicula cryptocephala,Cocconeis placentula,Lemnicola hungarica.These diatom species largely belong to ?-semi-spebic indicator species and ?-semi-spebic indicator species,which indictated that water quality.The result show that many ditoms that mentioned above largely appered in ZX?PL?YG?XG?AM?ZH.That means the nutrition of these rivers were higher than others.The GDI of 51 samplings were differens.The highest GDI appered SJWS12.And in the DSATS3 the GDI were lower than other sampling stations.The percentage of motile diatom ranged from 78%~0.41%.Bacillariophyta divided number ranged from 0~1 Analyzing the epipelic diatoms by the method of RDA indicated that the majority of attached algae were positive correlated with TN and Si O2;species such as Navicula gregaria,Gomphonema pala,Cocconeis placentula were negative correlated with TN;Achnanthedium minutis,Stigeoclonium and Cocconeis placentula were positive correlated with DO.