白水河国家级自然保护区柳杉（Cryptomeria fortunei）人工林大型土壤动物群落特征.

[Objective] The objective of the present study is to reveal the composition and seasonal variations of soil macrofauna communities in Cryptomeria fortunei plantations. [Method] Two Cryptomeria fortunei plantations were selected in the Baishuihe Nature Reserve, Sichuan province, and soil macrofauna communities were investigated in November 2019 and February, June and August 2020. The macrofauna at soil depths of 0 -15 cm were collected by hand-sorting. [Result] A total of 160 individuals of soil macrofauna were collected during this study and identified into 3 phyla, 5 orders and 44 taxa. On average, the macrofauna density was 26. 67 ind · m-2. The macrofauna communities were dominated by Diptera larvae and Coleoptera larvae, accounting for 38. 13 % and 16. 25% of the total number of soil macrofauna, respectively. The soil macrofauna were mainly herbivores. The Morisita-Horn similarity indexes between sampling months were higher than the Sorensen similarity indexes, indicating that the month effect on the community composition of the soil macrofauna communities was stronger than that on the abundances of the dominant groups. The abundance, taxonomic group, Shannon index, Margalef index, Pielou index, Simpson index of the soil macrofauna communities changed non-significantly among months. Similar responses were found for the abundances of herbivores, predators, detritivores, omnivores and other trophic groups. The results showed that the soil macrofauna communities were not sensitive to seasonal changes. Diptera larvae and Coleoptera larvae varied significantly among months (P < 0. 05 or 0. 001). And Diptera larvae were recorded only in February and June. Soil organic matter and total nitrogen were significantly and positively correlated with the abundance, richness, Margalef index the soil macrofauna communities, and the abundances of other orders and omnivorous (P < 0. 05 or 0. 001). The results showed that soil organic matter and total nitrogen were the main factors that determined the abundances and diversities of the soil insect communities. [Conclusion] All results suggest that the abundance and diversity of the soil macrofauna communities in Cryptomeria fortunei plantations have no significant seasonal difference, but the seasonal variation of taxonomic composition of the macrofauna communities is obvious. [ABSTRACT FROM AUTHOR]