乌兰布和沙漠植被数量分类及环境解释

Numerical classification and environmental interpretation of desert vegetation in the Ulan Buh Desert

植被与环境的关系研究一直是植被生态学研究的热点问题。应用双向指示种分析(TWINSPAN)方法对乌兰布和沙漠植物群落进行分类,应用典范对应分析(CCA)方法建立植物群落与地理位置、气候和土壤因子间的对应关系,以明确乌兰布和沙漠主要植物群落类型及影响群落变化和分布的主要环境因子。研究表明;乌兰布和沙漠天然植被由51科161属318种植物组成,可划分为30个群落类型。海拔、降水量以及土壤水分、粒度和养分是影响沙漠植被物种组成及其分布的主要因子。梭梭(Haloxylon ammodendron)、沙冬青(Ammopiptanthus mongolicus)、白刺(Nitraria tangutorum)、沙蒿(Artemisia desertorum)、沙米(Agriophyllum squarrosum)等主要植物群落生境对应较高沙粒含量,分布范围广;盐爪爪(Kalidium spp.)、马蔺(Iris lactea)、柽柳(Tamarix spp.)和芦苇(Phragmites australis)群落生境对应较高的土壤水分、盐分和粘粒含量,属于小生境群落;油蒿(Artemisia ordosica)、沙生针茅(Stipa glareosa)群落生境对应较高的降水量,分布于沙漠东部。因此,在乌兰布和沙漠生态保护与固沙植被建设中,应加强对土壤生境的保护,并针对不同区域的生境特点选择适宜的固沙植物及其恢复管理措施。

The relationship between vegetation and environment has always been a hot issue of vegetation ecology.In order to determine the main plant communities and the main environmental factors affecting the change and distribution of community types in Ulan Buh desert,TWINSPAN classification method was used to classify vegetation types,CCA correspondence analysis method was used to study the numerical relationship between vegetation communities and geographical location,climate and soil factors.Results showed that natural desert vegetation of Ulan Buh desert was composed of 318 species belonging to 161 genera and 51 families,which could be divided into 30 communities.The vegetation composition and distribution in Ulan Buh desert were the result of the comprehensive effects of geographical location,climate and soil factors,among which elevation,precipitation,soil moisture,soil particle size and soil nutrients were the main factors affecting the composition and distribution of desert vegetation.Haloxylon ammodendron,Ammopiptanthus mongolicus,Nitraria tangutorum,Artemisia desertorum,Agriophyllum squarrosum communities,et al.had the habitats with high soil sand content,and wide distribution regions.Kalidium spp.,Iris lactea,Tamarix spp.and Phragmites australis communities had high soil water content,salt content and clay content,and distributed in some niches.Artemisia ordosica and Stipa glareosa communities had high precipitation,and distributed in the eastern desert.Based on the above research results,we should pay attention to the protection of soil habitats while strengthening vegetation protection,and select suitable sand-fixing plants and restoration measures for the different habitats in the ecological protection and sand-fixing vegetation construction of Ulan Buh desert.