RESUMEN
To understand the characteristics of community structure and spatial distribution of small mammals in agricultural area of Yunnan Province, a systematic investigation was carried out in 104 quadrats of 25 regions in Yunnan Province from August 2010 to April 2018 by rat trap night method. The spatial variation of community characteristics along environmental gradients was analyzed by community ecological indicators. The results showed that a total of 3240 small mammals were captured and cold be classified into 42 species in 21 genera, 9 families, and 4 orders. The largest number of small mammal was rodents, dominated by Apodemus chevrieri and Rattus tanezumi. The 25 regions were clustered into three classes. The altitudinal distribution of small mammals was similar to the latitudinal distribution in agricultural areas. The number of species was relatively less in the low latitude and altitude range, with Rattus spp. and Mus spp. as the dominant species. In the high latitude and altitude region, the dominant species changed into Apodemus, Niviventer and Eothenomys. With the increases of altitude, the diversity index showed unimodal distribution, with the highe-st species diversity occurred in the mid-altitude area. The diversity index of small mammal showed the "V" type pattern in longitude, being the highest in the 98°-99° E gra-dient zone. At the latitude level, it showed an overall upward trend from south to north. Results from the GAM analysis showed that the degree of influence on the small animals in the agricultural area was in order of longitude, altitude and latitude. The similarity analysis in the composition of small mammals showed that the moderate similarity occurred in the adjacent gradient zone, and the highest similarity occurred in middle altitude zone, middle latitude zone, and low longitude zone. The farther the distance between different gradient zones, the lower the similarity of community structure. There was high spatial heterogeneity in different dimensions of small mammals' community structure in Yunnan Province. The geographical distribution trend of species diversity showed different distribution patterns across environmental gradients.
Asunto(s)
Biodiversidad , Mamíferos , Agricultura , Altitud , Animales , China , MurinaeRESUMEN
BACKGROUND: Rare investigation on tick-borne pathogens was carried out in Yunnan, China. In this study, we did a survey on Ehrlichia infection in small mammals and ticks. A total of 40 small mammals and 49 ticks were collected from Tengchong, Yunnan province. PCR targeting 16S ribosomal RNA (rRNA), citrate synthase, GroEL heat-shock protein operon, and major outer membrane protein genes was performed and positive amplicons were sequenced. RESULTS: The 40 small mammals were identified as 10 species, 2 (5.0%) of which were infected with Ehrlichia, 4 (10.0%) were infected with Anaplasma phagocytophilum and another 2 (5.0%) were infected with Candidatus Neoehrlichia mikurensis. Six (12.2%) ticks were positive for Ehrlichia and another two (4.1%) were infected with A. phagocytophilum. Neither small mammals nor ticks had coinfection. The detected Ehrlichia was named as Ehrlichia sp. YN04, which was in the same clade of Ehrlichia sp. 360 by phylogenetic analysis. The sequences of the pathogen recovered from small mammals and ticks were identical with each other. CONCLUSION: The study reports one Ehrlichia species first detected from small mammals and ticks in mainland China. As Yunnan is a famous "Global Biodiversity Hotspot" in the world, we may expect much more tick-borne infectious pathogens existing and declare more public health attention in this region.