Abstract: To explore the diversity and spatial distribution pattern of community species in the Qaidam Basin, we calculated the species composition and diversity index of plant communities in five different habitats, and analyzed the relationship between species diversity and altitude in different habitats. The results showed that 79 species of plants were recorded in the area along Delingha-Hala Lake, and the main dominant families included Compositae, Gramineae, Leguminosae, and Cruciferae. The species diversity of different habitat types had similarities, but also differences. According to the results of the community similarity in species composition, the species composition similarity between the alpine cushion vegetation and the alpine Potentilla fruticosa shrub meadow was the highest, while that of the alpine Kobresia myosuroides and the weedy meadow was the lowest. The species richness and diversity of the community showed a trend of first decreasing and then increasing with the altitude increasing, but the uniformity remained stable. In addition, the community species diversity in the middle-altitude area was the highest, and the community species diversity in the low-altitude area was slightly higher than that in the high-altitude area. The main reasons for the difference in species composition and diversity in different habitats were the hydrothermal conditions and species competitiveness.

Key words: Delingha-Hala Lake, Species diversity, Diversity index, Altitude

摘要： 为探讨柴达木盆地的群落物种的多样性和空间分布格局，本文以德令哈-哈拉湖沿线区域为研究对象，测定了5种不同生境下群落的物种组成和多样性指数，并分析了不同生境下群落物种多样性与海拔的关系。结果表明：该区域共记录了79种植物，菊科、禾本科、豆科、十字花科为当地的优势科种。不同生境类型的物种多样性具有相似性，但也存在差异性。从物种组成的群落相似性结果来看，高寒垫状植被与高寒金露梅（Potentilla fruticosa）灌丛草甸的物种组成相似性最高，而与高寒嵩草（Kobresia myosuroides）、杂类草草甸的物种组成相似性最低。随着海拔升高，群落物种丰富度和多样性呈先降低后增加的趋势，但均匀度保持稳定；中海拔区域的群落物种多样性最高，低海拔区域的群落物种多样性略高于高海拔区域，而造成不同生境群落物种组成和多样性差异的主要原因是水热条件和物种竞争力。

关键词: 德令哈-哈拉湖, 物种多样性, 多样性指数, 海拔