The seedlings of six sand-fixing shrubs were grown in the pots whose soil moisture contents were controlled by weighing to simulate suitable water condition,moderate drought,and severe drought for a long time,and the suitable water condition was taken as the control to determine biomass changes under water stress and analyze their drought adaptability as well.The results showed that as the soil moisture content reduced,total biomass and its components of every shrub were declined without exception.But in response to the soil moisture,the aboveground biomass proportion in total biomass decreased while the root biomass proportion in total biomass and root-shoot ratio all increased.The aboveground part biomass was affected by the soil drought greatly,and the underground part biomass was not affected much by water stress.All the six shrubs showed definite drought resistance,and could accommodate moderate drought. Moreover,Caragana korshinskii,Atraphaxis bracteata,and Atriplex canescens showed good adaptation to severe drought.Among six shrubs,the strongest in drought resistance was Atraphaxis bracteata,followed by Caraganakorshinskii and Atriplexcanescens.Hedysarummongolicum and Hedysarumscoparium were in the third place.Buddlejaalternifolia was comparatively weak in drought resistance.In their roots there were the common characteristics for adapting to the soil drought,but their aboveground parts differed from each other in stem and leaf chages.%采用模拟长时间干旱的控水盆栽方法处理6种固沙灌木的幼苗,以适宜水分条件为对照,测定水分胁迫下的生物量变化并分析其抗旱适应性.结果表明：随着土壤含水量的减少,6个树种的总生物量及其组分(根、茎、叶)生物量均下降；地上部分生物量比例均减小,而根生物量比例及根冠比都增大.地上部分生物量受干旱影响较大,其次为植物株整体,地下部分所受影响较小.6种灌木均具有一定的抗旱性,都能适应中度干旱.毛条(Caraga-na korshinskii)、沙木蓼(Atraphaxis bracteata)、四翅滨藜(Atriplex canescens)对重度干旱具有适应性.沙木蓼抗旱性最强,其次为毛条、四翅滨藜,再次为杨柴(Hedysarum mongolicum)、花棒(H.Scoparium),醉鱼草(Buddleja alternifolia)较弱.6种灌木的根系在适应干旱方面有相同之处,但其地上部分、茎、叶却有各自的特点.
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