Distribution Pattern And Influencing Factors Of Soil Oribatid Mites Diversity Along Altitudinal Gradient In Evergreen Broad-Leaved Forest Of Tianmu Mountain

Vertical distribution of biodiversity in forest ecosystems has always been a hot research topic in community ecology.As the altitude changes,it creates a unique environment.Oribatida is one of the main groups of soil invertebrates,which plays a driving role in the process of decomposing organic matter,loosening and activating soil,and is an important participant in the material cycle of ecosystem.In May 2021,the experimental investigation was carried out in Tianmu Mountain National Nature Reserve,and the Tianmu Mountain was segmented from 300 m to 1500 m above sea level,with 12 altitude gradients.One 20 m×20 m quadrats were selected at different elevation gradients,and samples were collected in the litter layer and soil layer within the quadrats,and separated and identified in the laboratory.The aim of this study was to investigate the distribution pattern and influencing factors of soil mite diversity along altitudinal gradient in an evergreen broad-leaved forest in Tianmu Mountain.The results showed that:(1)a total of 6184 oribatid mites were captured in this experiment,including 592 adults and146 nymphs in soil layer.A total of 4429 adults and 1017 nymphs were collected from litter layer,belonging to 56 species and 32 families.There were differences between the litter layer and the dominant species of the soil layer,of which the dominant species of the soil layer were Lohmannia turcmenica and Protoribates paracapucinus,and the dominant species of the litter layer were Haplozetes paraminimicoma,Tectocepheus velatus and Platynothrus peltifer.It was also found that the genus Protoribates was widely distributed in both the litter layer and the soil layer at all altitudes.(2)The number of oribatid mites was different in soil layer and litterfall layer at different altitudes,and the number of oribatid mites in litterfall layer was significantly higher than that in soil layer(p<0.05).The structure of oribatid mite community is significantly differentiated by altitude gradient,and there are also significant differences in diversity and species composition of oribatid mite community in soil layer and litter layer(p<0.05).(3)Oribatid mite communities were affected differently by environmental factors at different altitudes.The soil layer was mainly influenced by soil temperature and humidity,while the litter layer was mainly affected by p H,water content and plant richness,and showed a significant positive correlation.This study revealed the species composition and diversity of oribatid mite communities at different elevations in Tianmu Mountain and its relationship with environmental factors,and provides data support and theoretical basis for biodiversity conservation of subtropical forest ecosystem.