中文摘要：

应用分层半挖法研究了石羊河流域荒漠区主要固沙植物梭梭、红柳、白刺吸水根系根重密度分布规律、根系表面积变化规律以及与对应的微环境因子相关性。结果表明：梭梭、红柳、白刺根系长度受粘土层阻碍较大，随着植物根区粘土层的出现，粘土层以上靠近粘土层根系密度增大，粘土层以下远离粘土层根系密度先增大再减小，但物种不同，呈现这种规律的根级并不相同，梭梭表现为小于1mm根系，红柳和白刺表现为1～2mm根系与2～5mm根系；根系表面积变化亦具有这种特点。土壤容重对荒漠植物根系影响较大，土壤分形维数、土壤含水率和土壤有机质含量与对应的根系指标显著性不高。

英文摘要：

The distribution regularity of the density, variations of surface areas of fine roots, as well as their correlationship with related micro-environmental factors of some major sand-fixation plants were investigated, such as Haloxylon amrnodendron, Tamarix ramosissima, and Nitraria sibirica in Shiyanghe River basin by layered and half digging method. The results showed that the main root length were obstructed by clay layer. The root weight density increased when it reached the first clay layer and increased firstly, then decreased when it went through the clay layer. But diameter-classes were different among different plant species, 1 mm diameter class was embodied for H. ammodendron, and 1-2 mm, 2-5 mm for T. ramosissima, and N. sibirica. There was the same rule as root weight density. The correlation analysis to the root index and its environmental factors showed that soil bulk density influenced root growth largely, and there was not direct significant correlation between root amount and soil fractal dimension, soil moisture content and soil organic matter.