臭柏群落在不同演替阶段某些群落特征的研究

毛乌素沙地臭柏群落自发演替的基本过程为：半流动沙地沙竹 +沙米（有时是白沙蒿）群落→半固定沙地油蒿+臭柏群落→固定沙地臭柏+硬质早熟禾群落→固定沙地臭柏群落→老固定沙地臭柏+苔藓群落，最后可能发展成为地带性的本氏针茅草原。演替早期向演替亚顶级群落发展过程中物种多样性逐步增加，生态环境逐渐变湿。随着臭柏的衰退，某些喜湿植物的退出，物种多样性开始减少，群落生境向旱生化发展。

Community Characteristics of Sabina vulgaris Community under Different Stages of Succession

The autogenic succession process of vegetation in Mu Us Sandland is from Psammochlou uillosa + Agriophyllum arenarium (Artemisia sphaerocephala) on semi-drift-sand dunes to Artemisia ordosica + Sabina vulgaris on semi-fixed-sand dunes, then through S. vulgaris + Poa sphondylodes on fixed-sand dunes and S. vulgaris on fixed dunes of subclimax stage to S. vulgaris + moss community on old-fixed-sand dunes, which maybe pass to a Stipa bungeana steppe finally. The S. vulgaris community succession contains progressive and regressive succession. Species diversity increased with the development of the progressive succession, and the ecological environment began getting wet. Along with the declining of S. vulgaris, some plants exited, species diversity decreased and the habitat of community began getting dry.