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以2 mm为粗、细根的划分界限,采用根钻法对黄土高原安家沟流域油松、白杨、山杏、刺槐、沙棘和柠条6个主要造林树种细根分布进行研究,并测定不同林地下土壤含水率和土壤理化性质.结果表明:在水平方向上,油松细根生物量呈先增大后减小的二次多项式分布,其他5个树种细根生物量均呈对数分布,水平根系发达,细根主要分布在冠幅半径2~3倍的范围内,表明各植被通过水平扩展来获取更多的土壤水分.在垂直方向上,随着土层深度的增加,细根生物量均呈减小趋势.6种植被细根生物量与土壤水分、容重呈显著负相关,与有机质、全N含量呈显著正相关.
The fine root distribution of Pinus tabulaeformis, Poplar, Prunus armeniaca, Robinia pseudoacacia, Hippophae rhamnoides and Caragana korshinskii in the Anjialou valley on the Loess Plateau was studied by using 2 mm coarse and fine root demarcation line. The results showed that the fine root biomass of Pinus tabulaeformis first increased and then decreased quadratically in the horizontal direction, and the fine root biomass of the other five tree species showed a logarithmic distribution , The level of roots developed, the fine roots are mainly distributed in the crown radius of 2 to 3 times the range, indicating that the vegetation by horizontal expansion to get more soil moisture in the vertical direction, with the depth of the soil increases, fine roots The biomass of all the plants tended to decrease.6 The fine root biomass of six vegetation types was significantly negatively correlated with soil water content and bulk density, and positively correlated with organic matter and total N content.