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对沙地上不同年龄毛白杨（PopulustomentosaCarr．）人工林的根系，从形态、数量和分布密度3个方面进行了调查研究。结果表明，其根系为水平斜生复合根型，14a生林木根系的分布深度可达4．5m，水平根幅达8m左右。以重量划分7，9，14a生林分的根系，分别集中在0～60cm、0～100cm和0～100cm土层内，占根系总重的86％以上，树木周围2．0m范围内根系的重量占总根量的80％以上。以根系长度衡量，整个林地内根系分布较均匀，0～80cm土层内的根量占总根系量的78％以上。根系分布的密度和各径级根系的分布特点都依林木年龄、林地部位和土层深度不同而异。
The root system of Populustomentosa Carr. Plantations at different ages in the sand was investigated from three aspects of morphology, quantity and distribution density. The results showed that the root system of the root system was horizontal and oblique root system. The distribution depth of root system of 14a was up to 4.5m and the horizontal root reached about 8m. The root systems of 7,9,14a stand were divided by weight into 0 ~ 60cm, 0 ~ 100cm and 0 ~ 100cm soil layers, accounting for more than 86% of the total root system, and the root system within 2.0m around the trees The weight of the total amount of more than 80% of the root. According to the length of root system, the distribution of root system in the whole woodland was more uniform, and the root volume in 0 ~ 80cm soil layer accounted for more than 78% of the total root system. The distribution density of root system and the distribution characteristics of root system of different diameter all vary according to forest age, woodland location and soil depth.