Differential impact of land-use, season and soil characteristics on the abundance of edaphic springtails (Insecta: Collembola) and mites (Arachnida: Acari)

Land-use types exert a differential impact on soil quality and on the dynamics of edaphic (soil-dwelling) arthropods. This study determined the quality status of soils under different land-use categories (i.e. agricultural crop land, orchard land and natural uncultivated land) and different land-use types (i.e. sugarcane, fodder and rice-wheat fields, intercropped and non-intercropped citrus and guava orchards, natural grassland, bare land and wetland peripheries) using population abundance and dynamics of edaphic springtails (collembola) and mites (acari) as bioindicators. Using metallic soil corer (10 cm length and 10 cm diameter), extensive random soil sampling was carried out from selected localities in district Sargodha (Punjab, Pakistan) and soil microarthropods (i.e. springtails and mites) were extracted from composite soil samples using Tullgren-Berlese funnel. Impact of collection seasons (i.e. spring, summer, autumn and winter) and impact of different land-use types or categories on the population abundance of soil microarthropods was assessed. Moreover, soil physico-chemical and microbiological properties were also determined in order to find out the main edaphic drivers which can explain the population dynamics of these microarthropods. Results revealed that all major factors i.e. land-use types and categories, collection seasons and soil properties had a significant impact on the population abundance of springtails and mites. Agricultural soils harbored maximum abundance of both microarthropods followed by orchard land-use types, while minimum arthropod abundance was recorded for soils under natural land-use types. Similarly, maximum and minimum arthropod captures were recorded during spring and autumn seasons, respectively. Moreover, population dynamics of springtails and mites had a significant positive correlation with organic matter and total organic carbon contents, while had a significant negative correlation with soil bulk density. Conclusively, this study demonstrates the differential impact of land-use, season and soil conditions on the population abundance of edaphic microarthropods suggesting their suitability to be used as bioindicators of prevailing soil status.