Community structure of soil mites under different crops and its response to environmental factors in the buffer zone of Shibing Karst World Natural Heritage

Abstract

To reveal the differences in the community structure of soil mites under different crop environments in the buffer zone of the Shibing Karst World Natural Heritage Site, soil mites from corn fields (CF), pear tree lands (PL), tobacco fields (TF), grape fields (GF), and plum gardens (PG) were collected in the buffer zone in January 2022. Through the identification of mite specimens and data analysis, differences in the number of families, genera, individuals, individual density, diversity, similarity of communities, ecological groups of oribatid mites, and responses to environmental factors of soil mites under different crop environments were determined. The results showed that: (1) A total of 6941 soil mites were captured in the study area, belonging to 130 genera, 75 families, and 3 orders. The number of soil mite genera (CF and TF > PL > PG > GF) and number of soil mite individuals (PG > PL > GF > TF > CF) showed characteristics of differential distribution and surface soil aggregation in the five habitats. (2) Scheloribates, Protorobotritia, and Tectocepheus were the dominant genera in the study area. Lohmannia, Scheloribates, and Tectocepheus, representative species that indicate a good soil environment, were distributed in the sample plots of CF, PL, and PG to varying degrees, indicating that the ecological environment of these three crops was healthy. (3) The diversity index of PG was the highest, and similarity analysis of the five habitats revealed that they were at a medium level of similarity. (4) The ecological groups of oribatid mites in the different crop environments were dominated by the overall (O) type, which is a combination of Macropylina, Gymnonota, and Poronota. (5) The community structure of soil mites was sensitive to bulk density (BD), natural water content (NWC), total nitrogen (TN), total phosphorus (TP), total potassium (TK), available potassium (AK), and soil organic matter (SOM). Based on the above results, there were differences in the community structures of soil mites under different crop environments in the study area. The identification of the dominant mite genera can preliminarily indicate the environmental conditions of different crops, and a special correlation exists between the community structure of mites and environmental factors. Studying the community structure of mites in different crop environments in the Shibing Karst World Natural Heritage Site buffer zone is important in ensuring the ecological protection and sustainable development of the buffer zone. Furthermore, the results of this study support the role of the buffer zone as an ecological protection barrier for the heritage site.