内蒙古沙生植物的区系特征

内蒙古有沙生植物48科,177属,378种,50变种,其中荒漠区的沙生植物39科,122属,213种,草原区46科,158属,309种,表现出草原区的沙生植物更为丰富。科属组成上,是以豆科、菊科、藜科、禾本科为主,蒿属、虫实属、棘豆属、黄芪属为含沙生种类较多的属。生活型从种数上虽均以多年生草本为主,其次为一、二年生草本,但灌木与半灌木在群落中常具有重要的作用,尤其是在荒漠区,成为植被的基本层片。水分生态类型较为贫乏,以旱生为主,中生占有一定比例。区系地理成分上,荒漠区以蒙古成分和戈壁成分为主,草原区以蒙古成分和东亚成分为主,而温带成分均具有较大的比例,反映出地理位置及与周边地区的联系。

The Flora Characteristics of Sandy Plants in Inner Mongolia

In this paper,specific composition,life form,water ecological type and floristic geographic element of sandy plants in Inner Mongolia were analyzed.The results show that: There are 48 families,177 genera,378 species and 50 varieties in Inner Mongolia,in which 39 families,122 genera,213 species in desert region and46 families,174 genera,370 species in steppe region.It indicates that sandy plants are more abundant in steppe region.Leguminosae,Compositae,Chenopodiaceae and Gramineae are dominant families,ArtermisiaL.,CorispermumL.,Oxytropis DC.and AstragalusL.are main genera according to specific composition analysis.Perennial herbs are the most abundant life form and annual-biennial herbs are secondary,but shrubs and half-shrubs usually play important action in the community,and as basic synusium in desert region.The water ecological typesof sandy plants are not abundant,xerophyte is the main type and mesophyte is the secondary.According to floristic geographic element analysis,the Mongolia and the Gobi are the main elements in desert region and the Mongolia and east-asia are the main elements in steppe region,the temperate were important element,too.