Study On The Species Diversity Of Collembola In Jiuduansha Wetland, Shanghai

Springtails belongs to Arthropoda,Hexapoda,Collembola,they are a group of small soil animals.Because of their widespread distribution and sensitive to the changes of environment,they are often used as bioindicator for monitoring soil quality.At present,there are 9,000 species of springtails reported in the world,and more than 600 species have been recorded in China.Wetland is one of the most important ecosystems on the planet and has extremely important ecological service functions.However,the research on the species diversity of collembolan is still insufficient i,and there are few studies on wetland collembolan in China.The Jiuduasha Wetland,located in the Yangze River Estuary,mainly composed of Jiangya Nansha,Shangsha,Zhongxiasha and surrounding waters.It is the only estuary wetland in China that maintains its native status.Previous studies on the Jiuduansha Wetland were mostly focused on geology,geomorphology,water quality,and so on.However,the collembolan of Jiuduansha Wetland has not been investigated yet.In order to understand the species diversity and distribution pattern of springtails in Jiuduansha Wetland,this study selected 6 plots based on the main vegetation types and the height of the tidal flat.From March 2018 to April 2019,qualitative and quantitative surveys were carried out using sampling methods such as the ring knife,aspirator method and trap method.The results are as follows:1.Taxonomy of Collembola from Jiuduansha WetlandAfter detailed taxonomic identification in this study,it was found that there are 9 families,21 genera,28 species of collembolan from Jiuduansha Wetland,including 4 new species,which are Appendisotoma spinus sp.nov.?Folsomides anoculata sp.nov.?Folsomides cheni sp.nov.?Homidia jiuduanshaensis sp.nov.,and 4 new record:Choreutinula gauquelini Gers&Deharveng,1985?Friesea handschini Kseneman,1938?Archisotoma interstitialis Delamare Deboutteville,1953?Akabosia matsudoensis Kinoshita,1919.The dominan groups are Hypogastruridae,Neanuridae,Isotomidae,Tullbergiidae,Entomobryidae,Paronellidae,Sminthuridae,Bourletiellidae,Sminthurididae.Based on the findings,made a familia key to Jiuduansha Wetland Collembolan.The morphological descriptions of all the species were described,and the external morphological characteristics were photographed.The new species are described in detail,and related taxonomic papers are being published.2.Study on species diversity of Collembola from Jiuduansha WetlandThe distribution and community structure of collembolan in Jiuduansha Wetland were analyzed.The results indicate that Isotomidae and Entomobryidae the dominant groups in the area,among them,Proisotoma minuta and Proisotoma sp.are the dominant species in the region,accounting for 49.59%and 24.91%of the total number,the common taxa are Subisotoma sp.,Folsomides anoculata sp.nov.,Coecobrya pani and Sphaeridia sp.,which account for 20.33%of the total number,and the rare taxa account for only 5.17%of the total number of individuals.The density and number ofspringtails in Jiuduansha Wetland have obvious seasonal changes,the density of spring>the density of autumns>the density of summer,the average density of springtails in this area is 2695 individuals/m~2.In different vegetation,the Shannon-Wiener index,Pielou index,and Margalef index of Phragmites australis were all significantly higher than Zizania aquatica(p<0.05).Simpson index of Phragmites australis was significantly lower than Zizania aquatica(p<0.05),Spartina alternifklora and Zizania aquatica were not significantly different.In spring,the Shannon-Wiener index,Pielou index of collembolan in low tide beach significantly higher than high tide beach(p<0.05),Simpson index of collembolan in low tide beach significantly lower than high tide beach(p<0.05),and there is no significant difference in other.This study studied the community structure and species diversity of the collembolan in the Jiuduansha Wetland for the first time,which enriched the record of collembolan species in China.It might benefit to the protection of wetland ecosystems and species diversity in the future.