中文摘要：

对河北北部塞罕坝森林-草原交错区土壤节肢动物的群落结构特征及季节变化进行了调查．结果显示，交错区3个地带（森林带、森林-草甸带和草甸-草原带）土壤节肢动物群落的优势类群组成相似，均为蜱螨目和弹尾目，但不同生境中优势类群所占群落总数的比例不同，并且各样地常见类群和稀有类群的组成差异较大．3个地带土壤节肢动物群落类群数与DG多样性指数的季节变化总体表现为秋季多样性最高，夏季次之，春季最低，同时各样地土壤节肢动物群落因生境条件不同而形成各自的季节消长特点．3个地带土壤节肢动物群落类群数随着土层的加深而递减，具有明显的表聚性．

英文摘要：

Soil animals have been received more and more attention because they play an important role in nutrient cycling and they are considered as a potential bio-indicator of soil fertility in the terrestrial ecosystem. However, there is lack of information on the soil arthropods in the forest-steppe ecotone, which is necessary for the protectron of the biodiversity in this area. This paper provides the study on the structure and seasonal change of soil arthropod communities in the forest-steppe ecotone in northern Hebei, China. Soil macrofauna were obtained by hand-sorting. Mesofauna were separated and collected from soil samples by Tullgren method. By preliminary identification, the dominant groups were included in Acarina and Collembola, and they were similar in three study areas （forest area, forest-meadow area and meadow-steppe area）, but their proportions in different areas were different. Also, the compositions of common and rare groups of arthropods differed in the three areas. The group numbers and DG indexes of the soil arthropod communities in autumn were the highest, while those in summer were lower and in spring were the lowest. At the same time, the seasonal changes of soil arthropod communities in different areas were affected by habitat conditions. The group number of the communities decreased with the depth of soil, obviously showing the nature of surface gathering in the three study areas.