西双版纳2种热带雨林类型土壤节肢动物群落结构及分布特征

分析了西双版纳山地雨林和季节雨林土壤节肢动物群落的组成、分布特征及多样性状况。 2块样地 2次取样 ,共获取大、中小型土壤节肢动物 6 6 0 6个 ,分属 2 3目。蜱螨目、鞘翅目、弹尾目、膜翅目仍是 2林地土壤节肢动物群落组成共有的优势类群 ,但它们在不同样地生境中构成的数量比例不同 ,而常见和稀有类群组成较为复杂且样地间的差异更为突出 ,总体表现出季节雨林具有更多的热带成分 ,山地雨林则界于热带和亚热带之间。土壤节肢动物类群总数、个体总数及重要生物类群 (个体数量在 10 0 0个·m- 2 以上 )的分布 ,表现为山地雨林 (2 2类 ,4 974个 )多于季节雨林 (19类 ,16 32个 ) ,垂直分布结果表明 2类林地均具明显的表聚现象。从多样性尺度看 ,山地雨林密度 -类群指数高于季节雨林 ,这与 2林地土壤条件的优劣相符合

The Characters of Structure and Distribution of Soil Arthropod Communities in Two Types of Tropical Rain Forests in Xishuangbanna,Southern Yunnan

Composition of groups, distribution of individuals and diversity of soil arthropod communities in the tropical montane rainforest and tropical monsoon rainforest of Xishuangbanna were studied in September and December 1999. The results show that the total number of arthropods collected are 6 606 which consist of 23 orders. Acari, Collembola, Hymenoptera and Coleoptera were dominant groups in each habitat, but their proportion in different habitats were difference. There are great differences in the ingredient and common groups of soil arthropod communities among each habitat. There are more tropical characteristics for soil arthropod communities in the tropical monsoon rainforest than that in the tropical montane rainforest. The distribution of groups, individuals and important genera (the density>1 000·m^-2)of soil arthropods in the tropical montane rainforest (22 order, 4 974 individuals) are higher than those in the tropical monsoon rainforest (19 order, 1 632 individuals). The character of vertical distribution is that the individuals and groups of soil arthropods on the ground are more than those in the soil. There are difference between the Shannon Wienner diversity indexes and DG index of soil arthropod communities structure in two different tropical rain forests. Because of dominant group (Acari)individuals is larger in the tropical montane rainforest, it has the J, H' indexes of soil arthropod community in the tropical montane rainforest decreased, and it is less than that in tropical monsoon rainforest. The DG index are proposed on the base of the hypothesis that every species has equal independence and importance in the community, and can be compared with in community. So it is good to use DG index to measure the complicated soil arthropod community diversity. The results show that the richness and DG indexes in the tropical montane rainforest are much higher than those in tropical monsoon rainforest. It is positively related with the contents of soil organic matter and total N.