Abstract: The Stipa baicalensis meadow steppe of the Songnen Plains of China thrives with some of the plants of Mongolian flora,Northeastern China flora,Dahuricia flora,and China North flora.In the 27 sample sites set up in the area,there exist 153 species of plants belonging to 34 families,6 plant growth forms,5 root growth forms,6 life forms,4 water-requiring ecotypes,15 areal types,and 6 forage value types.Among them,the species of Compositae makes up 20.9% of the total,while Leguminosae and Gramineae each constitutes 11.8%.The species of limb type occupies 32% of the total plant growth form,and the tuff type and the endlong type each forms 24% and 18% respectively.About the root growth form,the dominant species is the brush root type which consists of 55%,the taproot type 18%,and the rhizome type 16% of the total.The life forms of most of the plants belong to the hemicryptophyte which forms 40%,the geophyte 29%,and the hemicryptophyte-geophyte 15%.The species of mesophyte dominates the ecological type of water,making up 51%,and the mesoxerophyte 34% of the total.The species of Mongolian-Northeastern China-Dahuricia-China North areal type forms 29%,and the Mongolian-Dahuricia areal type 13% of the total.Among the forage value type,the species of middling and low quality take as much as 52% of the total,while the high and fine quality species make up only 22%.In conclusion,the stipa baicalensis meadow steppe of the Songnen Plains represents a temperate herbage community,with a typical temperate hemicryptophyte climate,a mesophitic habitat condition,and complex diversities of forage plants with different grades of feeding value.

Key words: Stipa baicalensis, Meadow steppe, Growth form, Life form, Ecological type, Areal type, Forage value type, Structure type

摘要： 松嫩平原贝加尔针茅草甸草原是蒙古植物区系、东北植物区系、兴安植物区系和华北植物区系4个植物区系相汇集的区域,在全区所设的27个调查样地中,共有153种植物,隶属于34个科,6个株生长型,5个根生长型,6个生活型,4个水分生态类型,15个分布区型和6个饲用价值类型。其中,菊科种类最多占20.9%,豆科和禾本科分别占11.8%;株生长型结构以分枝型种类最多占32%,丛生型和直立型分别为24%和18%;根生长型结构以刷状根的种类最多占55%,直根型和根茎型分别为18%和16%;生活型结构以地面芽植物最多占40%,地下芽植物次之占29%,地面-地下芽植物占15%;水分生态类型结构以中生型种类最多占51%,中旱生型次之占34%;分布区型结构以蒙古-东北-兴安-华北分布区型的种类最多占29%,蒙古-兴安分布区型次之占13%;经济价值类型结构以中、低等质量的种类最多,所占比重高达52%,而优、良牧草种类只占22%。松嫩平原贝加尔针茅草甸草原具有温带草本群落植株和根系的特点,典型的温带地面芽植物气候特征,中生生境条件,复杂的分布区型结构和多样的饲用价值类型。

关键词: 贝加尔针茅, 草甸草原, 生长型, 生活型, 生态类型, 分布区型, 饲用价值类型, 结构型