重庆四面山根系及土壤特性对优先路径分布的影响

通过分析不同土地利用状况(林地,灌草地和农地)下优先路径分布特征、土壤特性、及根系状况,探讨根系和土壤特性时优先路径的影响.采用染色法分析了三种不同土地利用状况下6块样地的优先路径分布,并分析了优先路径与根长密度、根孔和根面积之间的关系.结果表明,所有土地利用状况下0～10 cm土壤染色面积超过50％,在20 cm以下...

Effect of Roots and Soil Properties on Preferential Flow Paths Distribution in Simian Mountains, Chongqing

In order to investigate the distribution characteristics of preferential flow paths under different land uses （forestland, shrubs land, and farmland） , the effects of roots and soil properties on preferential flow paths were explored. Dye tracer experiments were carried out on six sites with three types of land use. The relationships between the preferential flow paths and root lengths per soil volume, root holes and root surface area were analyzed by partial correlation method. Results showed that the upper 0 - 10 cm depth of the soil in all land uses had more than 50% dye coverage,and below 20 cm depth, the dye stained area was less than 30%. The soil organic matter content was approximately 5 - 20% higher in the preferential flow paths area than that in the soil matrix. The percent of preferential flow paths in soll was significantly affected by roots with a diameter of less than 5 ram, root holes and root surface area. The vertical distribution is quite different in various land uses. Shrubs land and farmland have more preferential flow paths in the top soil layers than forestland, and the situation conversed in deeper soil layers.