Soil Meso- and Micro-fauna Characteristics in Evergreen Broad-leaved Forest and Deciduous Broad-leaved Forest in Dajinshan Island, China

Soil meso- and micro-fauna across 8 plant communities in Dajinshan Island were investigated in the seasons of autumn (October), winter (December) in 2017, and spring (March), summer (June) in 2018. Totally, 8 506 soil animals were captured that belong to 5 phyla, 14 classes, and 23 groups. Among these animals, Nematoda, Acari, and Collembola were the dominant groups which accounting for 66.06%, 17.95%, and 11.15%, respectively. The others (4.84%) were belonging to rare groups. The annual average density and group number of soil meso- and micro-fauna in evergreen broad-leaved forest in autumn were higher than those in deciduous broad-leaved forest, and significantly different in group number (P < 0.05); Density of soil meso- and micro-fauna in summer was significantly higher than in other seasons that both in the two forests (P < 0.05); Group number of soil meso- and micro-fauna in evergreen broad-leaved forest in autumn was significantly higher than that in spring and winter (P < 0.05), and the number of deciduous broad-leaved forest in autumn was significantly higher than that in other seasons (P < 0.05). The density of soil meso- and micro-fauna in both two forests was higher in the surface layer, and in 0-5 cm soil layer in evergreen broad-leaved forest and 0-20 cm in deciduous broad-leaved forest that accounted for the fauna density of 68.68% and 66.94%, respectively. Shannon-Wiener and Margalef richness indexes in evergreen broad-leaved forest were higher than in deciduous broad-leaved forest, and they were higher in autumn than those in other seasons (P < 0.05); Shannon-Wiener index in deciduous broad-leaved forest in autumn was significantly higher than in other season (P < 0.05). Pearson's correlation show that the density of soil total, Nematoda, Acari and Collembola animals were positively correlated with soil organic matter, and negatively corrected with soil pH.