土壤入渗特性的空间变异规律及其变异源

以封丘地区典型的4种土地利用类型(传统耕作地、免耕地、金银花地和杨树林地)为例,系统研究了不同土地利用方式下土壤入渗特性的空间变异强度、空间变异结构及其主要变异源。结果表明,频繁的耕作会降低土壤异质性,弱化土壤特性空间变异结构,扰动较小的免耕地和金银花地的土壤入渗特性则具有相对明显的空间变异结构,扰动最小的杨树林地土壤的入渗特性具有最为明显的空间变异结构和最小的变程。容重、有机质含量和初始含水量是耕作地入渗的最主要变异源,初始含水量则是金银花地入渗的唯一显著性变异源;杨树林地入渗变异的主要变异源是有机质和初始含水量;影响免耕地入渗特性变异的变异源并不显著。在有些情况下,水温也可能成为入渗特性空间变异研究的重要干扰因素。

Regularity of spatial variability of soil infiltration and its variation sources

The influence of land use types on soil infiltration is one of the hot research topics in soil hydrology. In this research, four typical land use types in the Fengqiu region were chosen to systematically study the intensity, structure and main sources of the spatial variability of soil infiltration under different land use conditions. The result shows that the frequent cultivation can reduce soil heterogeneities, and thus weaken the spatial variability of soil structures. Compared to traditional tillage practices, soil properties exhibit high degree of apparent spatial structure in no-till and honeysuckle fields. The infiltration characteristic in forest soils, which received the least disturbance, varies most and exhibits a smallest range of variability among the four land use types. The soil bulk density, soil organic matter content and initial soil moisture are the major sources of variation for the spatial variability of soil infiltration. The initial soil moisture is the sole source of variation in the honeysuckle field. On the forest soil, the soil organic matter content and initial soil moisture are the major sources of variation. No significant variation sources are found on the no-till field. In some cases, the temperature of water could be an important factor to distort the spatial variability of soil infiltration.