不同土地利用类型植物根系与土壤抗蚀性关系研究

Study on relationship between plant roots and soil anti-erodibility of different land utilization types

对紫色土四种土地利用类型耕层土壤中植被根系分布特征进行量化分析,并在此基础上揭示根系分布与土壤抗蚀性评价指标的内在关系,以明确根系对土壤抗蚀性的影响机理。结果表明:小径级根系特别是径级<1 mm的根系对于>0.25 mm土壤团聚体形成和>0.5 mm土壤团聚体形成均有促进作用;<0.5 mm的根系长度与结构体破坏率、团聚状况、<0.001 mm颗粒含量和<0.01 mm颗粒含量均显著相关;竹林地根系含量最为丰富,<0.5 mm根系平均长度值最大,土壤团粒结构最好,其抗蚀性最强,传统农耕地根系稀少,其抗蚀性最差。

Based on the quantitative analysis of plant roots distribution characteristics of tilth soil under four land utilization types in Purple Soil,this paper revealed the internal relation between roots distribution and indicators of soil anti-erodibility,and made clear the influence mechanism of root on soil anti-erodibility.Results showed that root of minor diameter class,especially 1 mm roots,had promotion effect on formation of 0.25 mm 0.5 mm water stable aggregate.The length of 0.5 mm roots had remarkable correlation with rate of structure deterioration,the reunion situation,0.001 mm granule content,and 0.01 mm granule content.Due to the richest root content,the longest 0.5 mm roots and the best soil granular structure,anti-erodibility of bamboo forest land was strongest.Roots of traditional farmland were scarcity,and the anti-erodibility of it was the weakest.