Abstract: The study was conducted to reveal the soil moisture content of the fixed sanddune tops and the sandy land among the dunes; their dominant species, and their bio-diversity and similarity. The result shows that the soil moisture content of the inter-dunal land is much higher than that of the sanddune tops. Differences of species and quantity of plant communities between the sanddune tops and the inter-dunal areas also exist. The dominant species on sanddune tops are salix gordejevii and Areemisia intramongolica, while those in the inter-dunal land are Hedysarum and Artemisia sphaerocephala. The species diversity and similarity index of plant communities show that different ecological faclors not only significantly affect the distribution patterns of the dominant species and the subordinate species, but also greatly change the structures and functions of the plant communities.

Key words: Framing-pastoral zone, Fixed sand dunes, Biodiversity

摘要： 研究固定沙丘丘顶和丘间地土壤含水量、物种优势度、物种多样性与相似性。结果表明,丘顶和丘间地土壤含水量的差异较大,后者的土壤含水量明显高于前者,在丘顶和丘间地不仅植物种类和数量存在差异,而且优势种的序列亦发生较大变化,其中丘顶的主要优势种为黄柳和褐沙蒿,丘间则为羊柴和白沙蒿。群落中物种多样性与相似性指数表明,丘顶和丘间地植物群落生态因子的差异不仅对群落内优势种和从属种的分布格局产生较大影响,而且也导致群落结构和功能发生较大变化。

关键词: 农牧交错区, 固定沙丘, 生物多样性