大夏河甘南段河流湿地土壤节肢动物群落特征及季节动态

采用国际通用采样方法，在春、夏、秋三季对大夏河甘南段河流湿地6个样点土壤节肢动物群落进行了调查研究，比较分析了土壤节肢动物群落组成、多样性及其季节动态特征.结果表明：共捕获土壤节肢动物8 743只，隶属于3纲9目33科35类，其中，大型土壤节肢动物2 743只，占捕获量的35.52%；中小型土壤节肢动物6 000只，占64.48%；大型土壤节肢动物的优势类群为摇蚊科幼虫和长足虻科幼虫；中小型土壤节肢动物的优势类群为绥螨科、绒螨科、等节跳属和原等跳属. 在不同样点土壤节肢动物类群数和个体数量表现出了明显季节变化，其高低顺序为秋季>夏季>春季；不同样点土壤节肢动物的垂直分布具有明显的表聚特征，即从地表向下，随着土壤深度的增加土壤节肢动物类群数和个体数量逐渐减少.研究结果为进一步开展高原寒区河流湿地土壤节肢动物生态学研究提供了基础资料.

Characteristics and seasonal dynamics of the soil arthropod community in Gannan section of the Daxia River wetland

For understanding the characteristics of structure, diversity and seasonal dynamics of soil arthropod community in Gannan section of the Daxia River wetland, an investigation was conducted at six plots in spring, summer and autumn with field sampling method. It is found that (1) a total of 35 groups and 8 743 soil arthropod were captured, including 2 743 large-size ones and 6 000 small/medium-size ones, which belong to 3 classes, 9 orders and 33 families. Large-size soil arthropod accounts for 35.52% of the total, small/medium-size soil arthropod accounts for 64.48% of the total. The dominant groups of large-size soil arthropod include Chironomidae and Doilchopodidae; small/medium-size soil arthropod include Sejidae, Trombidiidae, Isotoma and Proisotoma; (2) There are significantly seasonal variation in the composition and individuals of soil arthropod community, and the sequences of seasonal dynamics of groups and individual number of the soil arthropod are characterized by autumn > summer > spring; (3) The vertical distributions of the group and individual density in a soil profile are characterized by concentration in surface in the depth range of 0~5 cm and decline with depth. These results will provide useful data for ecological study of soil arthropod in arctic-alpine wetland.