Effects of Natural Land Cover, Anthropogenic Disturbance, Space, and Climate on Oribatid Mite Communities in Canada’s Oil Sands Region

Abstract

Soil contains a diverse fauna and microflora that are vital for maintaining healthy soils and their various ecosystem services. Oribatid mites are typically highly abundant arthropods in the soil and are used as indicators for environmental monitoring. The aim of this study was to determine oribatid mite community response to natural land cover, anthropogenic disturbance, space, and climate in the oil sands region of Alberta, Canada. Our results found that oribatid mite total abundance was significantly reduced by mining, cultivation, and well sites. Species richness was significantly reduced by mining and cultivation. Shannon’s diversity index was significantly higher for all natural land cover types, seismic lines, and forest harvest. Additionally, species diversity was lower under the relative influence of energy-related soft linear disturbances than for naturally vegetated sites and forest harvesting, and was lowered further by anthropogenic disturbances with more impact on soil integrity (cultivation, mines, urban/industrial, road/trail verges, well sites). Abundance, richness, and diversity also increased with increased frost free period and with eastward longitude. Mite community composition included a notable composition difference between lowland habitats and upland forest types, and between natural land cover and intense anthropogenic disturbance types (e.g., mines, cultivation). Our study highlighted oribatid mite communities’ response to natural land cover, anthropogenic disturbance and spatial–climatic factors assessed over broad spatial scales and the potential utility of oribatid mites as ecosystem health indicators under multiple ecological drivers.