Community diversity of soil meso-fauna indicates the impacts of oil exploitation on wetlands

Soil meso-fauna can indicate ecological health and provide biotic metrics for evaluating ecosystem damage and environmental changes. However, the roles of the soil meso-fauna in wetlands affected by oil exploitation have rarely been studied. This study investigated the community of the soil meso-fauna and the soil environmental quality in the oil exploitation area (oil well area, transitional area, and natural area) of the Momoge wetland, China. The results revealed that the oil pollutants (polycyclic aromatic hydrocarbons, PAHs) in the oil exploitation area mainly contained 2–3 rings soil PAHs. Oil exploitation mainly affected the soil meso-faunal community by changing the soil environment and vegetation characteristics. The abundance and richness of the soil meso-fauna were negatively affected by oil exploitation, and the richness responded more sensitively than the abundance. The diversity and taxa composition of the soil meso-fauna can be used to indicate the impacts of oil exploitation on wetland ecosystems and assess the ecological health of wetlands. The terrestrial taxa of the soil meso-fauna in wetlands (Coccoidea, Carabidae larvae, Hydrophilidae larvae, and Aphididae) could tolerate the oil pollutants and intense exploitation disturbance, indicating a highly disturbed wetland ecosystem. The aquatic (Chironomidae) and terrestrial taxon (Tenebrionoidea) indicated an intermediately disturbed wetland ecosystem. The aquatic (Enchytraeidae and Tabanidae) and non-aquatic taxa (Lposcelididae, Oecobiidae, and Tenthredinidae) indicated an undisturbed natural wetland ecosystem. The results of this study provide promising opportunities for oil production management and conservation efforts for wetland resources and biodiversity.