Community Ecology Study On Small Animals And Their Parasitic Fleas In The Lower Reaches Of Jinsha River In Yunnan Province

ObjectiveThe purpose of this study is to clarify the structural characteristics,biodiversity and spatial distribution pattern of rodents and parasitic fleas in the lower reaches of Jinsha River in Yunnan Province,further supplement the ecological data of rodents and parasitic fleas in the Jinsha River basin,and provide scientific basis for the prevention and control of rodent diseases.MethodsIn order to achieve this goal,we took the lower reaches of the Jinsha River in Yunnan Province as the survey scope,and selected 62 sample sites in 6 sample areas according to different habitats,different latitude and longitude,and different altitude.From October 2017 to December 2020,we carried out a survey on murine animals and their parasitic flea.The results were statistically analyzed.The community structure and distribution pattern of rodents and their parasitic fleas as well as the parasitic relationship between rodents and surface fleas were determined.Results1.In this survey,17,281 clips(cages)of effective trapping tools were distributed in 62 sample sites,and 1,509 rodents of 31 species,15 genera,3 orders,6 families,were captured.The overall capture rate was 8.73%,and the dominant species was Apodemus auratus,accounting for 17.76%.There were 1174 parasitic fleas collected from 5 families,10 subfamilies,18 genera,26 species.The dominant fleas were Ctenopsyllus quadratus,Leptoplakia,remote Palaeopsyllus and Metaplakia,accounting for 23.08%,22.15%,14.05%,10.22%.2.α diversity characteristics: In the two habitats,the richness,diversity and evenness of rodents and fleas in agricultural areas were higher than those in residential areas,and the dominance of residential areas was higher,and the dominance of rattus norvegicus and R.flavus was obvious in this area.In terms of longitude and latitude,the richness and dominance of rodents were the highest in the B and b latitudes,and the diversity and evenness were the highest in the C and c latitudes.The species richness and diversity of parasitic fleas were the highest in the B and b latitudes,and the distribution was even.In the vertical distribution of altitude,the richness and diversity index of rodents and parasitic fleas increased with the increase of altitude,and the peak values appeared in the Ⅲ or Ⅳ altitude zone.The dominance of rodents was the highest in the Ⅳ altitude zone,and the dominance of Apodemus aureus was more obvious in this zone3.Community similarity analysis showed that the similarity coefficients between adjacent distribution zones were high and the spacing distribution zones were low for both rodents and fleas.In terms of habitat and spatial distribution,the similarity between rodents and fleas was greater than that between fleas,and most of them were moderately similar,while the similarity between fleas was moderately dissimilar or very dissimilar.In the zones Ⅰ andⅣ,the elevation ladder difference was the largest,the community replacement rate was the fastest,the Cody index of rodents was the largest,and the Cody index of fleas was between the zones Ⅱ and Ⅳ.4.On the body surface of the dominant rat species Apodemus auricularis,the most dominant species were Xenopsyllus speciosa and Diqingfrontera.The dominant fleas,Ctenopsyllus quadratus,were mainly parasitised on the body surface of the Chaotong velvet mouse and the large velvet mouse,Leptosylla celatus was mainly parasitised on the body surface of the yellow chest mouse and Rattus norvegicus,and the remote palaeopsyllus was mainly parasitised on the body surface of the Sichuan anova shrew.5.In terms of the relationship between rodents and their parasitic fleas,12 species,such as yellow chest mouse,Sikgold mouse and Rattus norvegicus,had relatively wide niche ranges and were distributed in the four altitudinal zones,while 8 rare species,such as white-vented mouse,Apodemus agrarius and giant vesiculus,had niche widths of 0.Most of the significant overlapping species pairs overlapped with R.nigrifolia,white-tailed shrew,R.flavus and Mus musculus.The three species,Lepidopsyllus chrysopsyllus,Xenopsyllus chrysopsyllus,and anisopsyllus anisopsyllus,are distributed in all four altitude zones.The named subspecies,Lepidopsyllus densiformis,Micranopsyllus anerotica,and Xenopsyllus enanthopsyllus,make full use of host resources and parasitism on a variety of rodent hosts.The number of significant species pairs overlaps with Ctenopsyllus quadratus and Frontalis diqingnensis was the largest in terms of altitude and host resources.Conclusions1.The species of rodents and fleas in the lower reaches of Jinsha River in Yunnan Province are rich and diverse.The dominant species of rodents is Apodemus Alpine,and the dominant fleas are named subspecies of Ctenopsyllus quadratus,Lepidopsyllus ploidus,Palaeopsyllus remote and Xenopsyllus exotica,all of which have a wide niche range.2.Compared with residential areas,murine animals and parasitic fleas have higher richness,diversity and evenness in farming areas;In the horizontal distribution,the abundance of rodents and parasitic fleas was the highest in the B longitude zone and b latitude zone.In the vertical spatial distribution,the richness and diversity indices of rodents and parasitic fleas increased with the increase of altitude.3.Both rodents and fleas have higher similarity coefficient between adjacent distribution zones and smaller Cody index,and the similarity of rodents among different communities is greater than that of fleas in habitat and spatial distribution.4.Paracerophora flexus was found for the first time in Yunnan Province in this survey,but its specific distribution needs to be further investigated.5.There are host vector bases for transmission and preservation of hemorrhagic fever with renal syndrome,forest encephalitis,leptosis,scrub typhus and plague in the lower reaches of Jinsha River in Yunnan province.