放牧干扰对亚高山草甸土壤动物群落影响的研究

摘要

对川西北红原县3个不同放牧强度(轻度放牧、中度放牧、重度放牧)的亚高山草甸土壤动物群落进行了调查研究,共获得土壤动物1 887个,分别隶属3门7纲15目49类群.不同放牧强度下土壤动物优势类群差异较大.受放牧干扰的亚高山土壤动物群落,其个体数量变化趋势是:重度放牧＞中度放牧＞轻度放牧.中度放牧生境的中小型土壤动物密度最大,大型土壤动物密度最低.3种生境中土壤动物的个体数和类群数均随土层加深而递减,其中中度放牧生境土壤动物表聚性最强.受放牧强度和放牧方式的干扰,中度放牧生境中土壤动物群落种类多样性、均匀性及丰富度均低于其他生境,而优势度高于其他生境.%Soil fauna in subalpine meadows of north-west Sichuan with various grazing pressures were studied to assess the influences of different grazing disturbances on soil fauna communities and to offer some scientific foundation for subalpine meadow ecosystem management.A total of 1 877 individuals were collected and found to represent 3 phyla,7 classes,15 orders and 49 groups.There were large differences in the dominant groups of soil fauna under different grazing intensities.The numbers of soil fauna in the various sites were in the order;heavy grazing>moderate grazing>light grazing.The individual density of soil micro-fauna was the highest while that of soil macro-fauna was the lowest.Both the individual density and the group number of soil fauna decreased with increasing soil depth and the numbers of groups and individuals of soil fauna in the moderately grazed habitat decreased most dramatically.With the disturbance of grazing pressures and forms,the diversities and evenness of abundance of soil fauna under moderate grazing were lower than those in other habitats,while the dominances were higher.