Abstract: To understand the community structure and its seasonal change of litter invertebrates in urban forests of Southern China, the litter invertebrates in Changgangshan Natural Reserve of Guangzhou were sampled monthly from July 2004 to June 2005. A total of 21817 invertebrate individuals belonging to 22 orders in 9 classes under 3 phyla were collected. Acarina and Collembola, the dominant groups of the litter invertebrates, had the individuals accounting for 70.3% of the total, and the individuals of the ordinary groups Helminthomorpha, Araneae, Isopoda, Thysanoptera, Coleoptera, Hymenoptera, Lepidoptera larvae, and Diptera larvae occupied 27.0% of the total. The relative abundance and density of these 8 groups changed with seasons, and orrelated with litter humidity to a certain degree. The highest density of Acarina occurred in heavy rainy seasons, i.e., from May to August, and that of Collembola appeared from February to July. Thysanoptera showed a high density from August to December, but the higher or lower litter humidity caused its low density in rest months. Coleoptera showed three density peaks, i.e., MayAugust, November, and next February. Helminthomorpha had the highest density in May and June, but very low density in the other months. The individuals ratio of Acarina to Collembola (A/C value) varied with sampling season significantly even at the same sampling site, and did not necessarily reflect the distribution characteristics of litter invertebrates in the same climate zone. To remain urban forest litter would be of significance in improving the invertebrate diversity in urban forest soil.

Key words: Gaps, Natural disturbance, Mid-subtropical evergreen broad-leaved forest