乌兰布和—西鄂尔多斯荒漠草原过渡带典型灌木群落及其多样性

目的] 研究乌兰布和沙漠—西鄂尔多斯荒漠草原生态过渡带典型灌木群落的多样性，为该区生物多样性保护和生态环境建设提供理论依据。方法] 通过重点精查的方式对该地区代表性群落类型设置样点进行植被调查，分析了该过渡带主要灌木群落的类型、物种组成、群落特征和物种多样性。结果] 该区共有12科30属36种植物。豆科、菊科、藜科和禾本科植物比例较高，单种属较多。多年生草本和灌木居多，以旱生植物为主。灌木群落包括分布在西鄂尔多斯荒漠草原的驼绒藜群落、霸王群落和四合木群落，分布在乌兰布和沙漠的白刺群落、油蒿群落和沙冬青群落。西鄂尔多斯荒漠草原灌木群落的植株密度较高，乌兰布和沙漠灌木群落的建群种重要值、盖度和地上生物量较高。西鄂尔多斯荒漠草原灌木群落的物种多样性普遍高于乌兰布和沙漠。大部分群落的相似性较低。结论] 乌兰布和—西鄂尔多斯荒漠草原过渡带植物数量比较贫乏，多年生草本和灌木是该区植物的主要部分，植物旱生化明显，西鄂尔多斯荒漠草原植物多样性变化幅度较小且保持在较高水平，不同生境下群落相似性较低。

Typical Shrub Communities and Its Diversity in Ulan Buh-Western Ordos Steppe Desert Ecotone

Objective] The diversity of typical shrub communities in the ecotone of the Ulan Buh-Western Ordos Steppe Desert was researched in order to provide a theoretical basis for protecting biodiversity and for ecological environment construction in the area. Methods] A vegetation survey was carried out by setting up sample sites of representative community types in the area. The community types, species composition, community characteristics, and species diversity of the main shrub communities in the ecotone were analyzed. Results] There were 12 families, 30 genera, and 36 species of plants in the area, among which there were more Fabaceae, Chenopodiaceae, Asteraceae, and Poaceae, and more single species. Plants were mainly composed of shrubs and perennial herbs. Most plants were xerophytes. The shrub communities included the Krascheninnikovia ceratoides community, the Scarcozygium xanthoxylon community, and the Tetraena mongolica community in the Western Ordos Steppe Desert, and the Nitraria tangutorum community, the Artemisia ordosica community, and the Ammopiptanthus mongolicus community in the Ulan Buh Desert. The plant density of the shrub community was higher in the Western Ordos Steppe Desert. The importance value, coverage, and aboveground biomass of the shrub community were higher in the Ulan Buh Desert. The species diversity of the shrub communities in the Western Ordos Steppe Desert was generally higher than in the Ulan Buh Desert. The similarity of most communities was low. Conclusion] The total number of plants in the Ulan Buh-Western Ordos Steppe Desert was relatively few. Perennial herbs and shrubs were the main types of plants in the ecotone. The plants exhibited obvious xerophytic characteristics. The variation range of plant diversity in the Western Ordos Steppe Desert was small and remained at a high level. Community similarity in different habitats was low.