中文摘要：

本文对中国干旱内陆荒漠区的幼龄天然胡杨树的根质量密度和根长密度分布进行研究。结果表明：在垂直方向上，根量主要集中于80cm-100cm的土层中，约占总量的38．75％，在100cm土层以下迅速下降，根长密度随土壤深度的变化，呈指数函数分布；在水平方向上，主要分布在距胡杨树干0cm—100cm范围内，且输导根（d〉2mm）占质量比重大。约占总量的88．67％，吸收根（d〈2mm）占根长比重大，约占总量的92．21％。

英文摘要：

The spatial distribution of the root length and weight density of young Populus euphratica in arid desert regions of China were analyzed. The main results showed that vertically ,the roots concentrated at the 80 - 100cm soil zone where the amount of roots accounted for 38.75% of the total, but the amount of roots below 100cm soil zone sharply decreased, and the root length density varied with the soil depth in a exponent curve; horizontally, the amount of the roots in the zone to 0 - 100cm from the tree row, and the d 〉 2ram root constitute the majority of weight while the d 〈 2mm root constitute the majority of length which accounted for 88.67% and 92. 21% of the total respectively.