中文摘要：

水分是影响干旱区沙丘植被分布、生长和生存的关键因素.以内蒙古自治区乌审旗达布察克镇周边8km范围为研究区域,对不同类型沙丘的土壤水分进行连续观测,研究城镇周边沙丘土壤水分时空动态变化规律.结果表明：研究区沙丘土壤含水量时间变化分为春季积累期、水分消耗期、秋季积累期、稳定期4个阶段.在空间分布上,不同沙丘土壤含水量大小表现为：流动沙丘〉半固定沙丘〉固定沙丘（纯蒿）〉固定沙丘（柳蒿混生）;沙丘土壤水分垂直变化可分为土壤水分速变层、土壤水分活跃层和土壤水分相对稳定层3个层次;从沙丘地形部位看,丘间低地地下水位高,而背风坡土壤含水量接近植物凋萎系数.

英文摘要：

Water is the key factor which determines the distribution,development and maintenance of the vegetation on sand dunes in arid and semiarid region.Based on continuous observation on water content in different types of sand dunes around 8 km far from Dabqig,the dynamic spatiotemporal change of water content in sand dune soil had been studied.The results showed that the seasonal dynamic change of water content could be divided into four periods：the accumulating period in spring,the water-consuming period,the accumulating period in fall and stable period.In spatial distribution,the sand water content was as follows：moving dune semi-fixed dune dune fixed by Artemisia ordosica dune fixed by Salix psammophila and A.ordosica.Vertical distribution of water content could be divided into the rapid change layer,active layer,and stable layer.The water content of leeward slope was lower than that of wilting coefficient,which was not suitable for planting,and the ground water level in inter-dune lowlands was high.