内蒙古两个不同温度型草原站点植物科属组成及生态类群对比

Comparison on Species Composition and Ecological Groups in Two Stations of Different Thermometric Types′ Steppe Region located in NeiMongol

在内蒙古草原区选择暖温型 (阿贵庙 )和中温型 (黑山头 )两个草原站点对其植物的科属组成 ,区系地理成份 ,生活型 ,水分生态类群和 C3/C4 光合功能群进行对比 .植物的科属组成反映出物种多样性随纬度增加而减少的趋势 ;科属的相似性较大反映出半干旱草原区植被科属组成的共性 ,而物种组成的相似性较小则反映了两站点植物随温度及水热组合状况的差异呈现出地理替代与区域分异的特征 .水分生态类群比例较为接近 ,反映出半干旱气候的共同作用 ,但 C3/C4 光合功能群比例差异较大 ,反映出 C4 植物随纬度增加 ,气温降低而减少的趋势 .

In two stations of Warmth temperature Steppe (Arguimiao Temple) and Moderate temperature Steppe (Heishantou) ,the contrast research has been carried out on species composition, floristic composition, life type spectrum, water ecological groups and C 3/C 4 photosynthetic functional group. Plant species composition shows that the species diversity decrease along with increase of the latitude. The result of similarity comparison demonstrates that families and genus in the stations is more similar respectively and the species is more discrepant .Larger similarity in the families and genus reflects that the general character of the vegetation in semi arid steppe region, but smaller similarity in species composition indicates the characteristics of geographic replacement and regional differentiation in virtue of difference in temperature and combination of water and heat of the two stations. The water ecological types proportion is very close, reflecting the mutual influences on the two stations in the semi arid steppe region. However, the proportion of C 3/C 4 photosynthetic functional groups is very disperity of them. There are only 5 species of C 4 plant (4.2%) and the ratio of C 3/C 4 plant equal to 22.4∶1 in Moderate temperature Steppe station and 22 species of C 4 plant (10.95%) and the ratio of C 3/C 4 plant equal to 8.136∶1, shows the tendency of C 4 plants′ quantity and proportion decreases along with increasing of latitude and decrease of atmospheric temperature.