中文摘要：

本文对科尔沁沙地流动沙丘不同坡位（丘间地、过渡带、迎风坡中部、坡顶、背风坡上部和下部）和不同土层深度（0～20、20～40和40～60cm）的土壤线虫群落组成与多样性进行了比较研究。研究结果表明，流动沙丘土壤线虫具有显著的坡位效应，而垂直分布特征不显著。丘间地和背风坡下部具有较高数量和较多种类的土壤线虫，而过渡带和迎风坡中部土壤线虫数量较低、种类也较少。不同坡位土壤线虫总数、食细菌线虫、食真菌线虫和植物寄生线虫数量存在显著差异。除食细菌线虫外，不同土层土壤线虫总数及其各营养类群均无显著差异。土壤含水量和电导率是影响土壤线虫群落空间分布格局的主要因素。土壤线虫群落分布格局的变化反映了流动沙丘土壤微环境的变化，对土壤质量具有一定的指示作用。

英文摘要：

Soil nematode community composition and diversity in six slope positions （lowland, ecotone, middle windward, top slope, and upper and lower leeward） and at three soil depths （0-20, 20-40 and 40-60 cm） along an active sand dune were studied in the Horqin Sandy Land. The results showed the significant effect of the slope position on soil nematode communities, but no of soil depth. The abundance and diversity of soil nematodes were higher in lowland and low leeward slope than in ecotone and middle windward slope. Significant differences in the abundances of total nematodes, bacterivores, fungivores, plant parasites and omnivores-predators were observed among slope positions. Only the abundance of bacterivores at different soil depths was significantly different. Soil moisture and electronic conductivity were the main factors which affected the spatial distribution pattern of soil nematode communities. The variation in soil microenvironment along an active sand dune could be reflected by the change in distribution pattern of soil nematode communities.