Distribution Patterns of Soil Fauna in Different Forest Habitat Types of North Hebei Mountains, China

The relationship between soil fauna distribution and forest habitat types is an ongoing concern. In this study, the distributions of soil fauna communities were investigated and compared in three forests of Betula platyphylla, Picea asperata, and Pinus sylvestris. A total of 39 groups of soil fauna belonging to four functional groups were found, with Acarina and Collembola being the dominant groups, and omnivorous and saprophagous being the dominant functional groups. An investigation on the temporal and spatial distribution of the soil fauna found similar changes in the three forests: the abundance of soil fauna was higher in August and September and lowest in May; explicit surface aggregation of the soil fauna emerged; and the density and group number decreased with the increase in soil depth. Via comparison, the total abundance of soil fauna in the B. platyphylla forest (16,772 ind m(-2)) was found to be higher than that in the P. asperata (12,972 ind m(-2)) and P. sylvestris (14,250 ind m(-2)) forests, and the indexes of diversity, richness and evenness of the soil fauna community in the B. platyphylla forest were the highest. Redundancy analysis showed that soil organic matter (SOC), total nitrogen (TN), and total phosphorus (TP) were positively correlated with soil fauna density, whereas pH and bulk density (BD) were negatively correlated. Compared with the two coniferous forests, the physicochemical factors positively (negatively) correlated with soil fauna density were the highest (lowest) in the B. platyphylla forest. The combined effect of these multiple factors suggests that the B. platyphylla forest recovered the most favorable conditions for the living and development of the soil fauna. The findings in this research may help us to understand the restoration effect of soil fauna in different forest habitat types, providing support for forest sustainable management in northern Hebei Mountain ecosystems.