阿拉善高原荒漠植被组成分布特征及其环境解释 Ⅴ.一年生植物层片物种多样性及其分布特征  

Environmental Effects on Distribution and Composition of Desert Vegetations in Alxa Plateau:Ⅴ.Biodiversity and distribution of annual plants

作　　者：何明珠[1] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所沙坡头沙漠试验研究国家站,甘肃兰州730000

出　　处：《中国沙漠》2010年第3期528-533,共6页Journal of Desert Research

基　　金：中国科学院“西部之光”项目;国家杰出青年基金项目(40825001);国家科技支撑项目项目(2007BAD46B03)共同资助

摘　　要：阿拉善荒漠常见的37种一年生植物,隶属于9科27属,可划分一年生藜科、一年生禾草、一年生蒿类和一年生杂类草共4个类群,主要由藜科的猪毛菜类构成,占总数的将近一半,其次为禾本科的小禾草类和菊科的蒿类。阿拉善荒漠一年生植物层片由12种区系地理成分组成,其中以亚洲温带、亚洲荒漠成分为主,阿拉善特有成分次之,表现出阿拉善一年生植物层片是作为古地中海旱生植物后裔的古老性和温带干旱荒漠的性质。通过Twinspan分类、CCA排序以及一年生草本物种多样性与环境因子的逐步回归,发现影响阿拉善荒漠一年生植物层片组成及分布特征的关键环境因素包括:第一类是水、热和光照条件,主要包括年均降水量、积温和光照时间;第二类是土壤的粉粒含量;第三类是表征土壤盐碱化程度的指标,包括SO24-、Mg2+、电导率、HCO3-。气候,特别是降水的波动直接决定着一年生草本植物在荒漠群落中层片构成,此外土壤质地也是一年草本植物定居和繁衍的重要基础,在一定的程度上支持了荒漠草地生态修复的理论假说。The common 37 annual plants in Alxa desert belong to 9 families and 27 genera, which can be divided into 4 groups, namely annual chenopod, annual short grass, annual artemisia and annual weeds. Annual salsola makes up more than half of the annual plants, followed by short grass and annual artemisia. Annual plants in Alxa desert belong to 12 floristic area-types, and are dominated by temperate Asia, Asia desert, followed by the endemic to Alxa, which indicate the antiquity of Tethys relics and characters of temperate arid desert. The relationship between annual plants biodiversity and environmental factors was analyzed by Twinspan classification, CCA ordination and stepwise regression. The results implied that the key environ- mental factors affecting annual plant composition and distribution are： the first type is water, heat and sunshine condition, including annual precipitation, accumulated temperature and sunshine hours; the second type is percentage of silt; the third type includes index about saline-alkali levels of soil, containing SO4^2-, Mg^2＋ and HCO3^-. Therefore, climate, especially the annual precipitation directly determine the annual plants composition in desert communities, in addition, soil texture also affect their settlement and propagation, which in a certain level examine and verify the theoretic hypothesis about ecological restoration in desert grassland.

关 键 词：生态恢复 分类 排序 逐步回归 阿拉善高原 

分 类 号：Q948.15[生物学—植物学]