六盘山华北落叶松坡面土壤饱和导水率空间异质性及其影响因素

为深入理解森林坡面土壤饱和导水率的空间变异,利用经典统计学和地统计学的方法研究六盘山华北落叶松人工林坡面不同土层土壤饱和导水率的空间异质性,并基于相关性分析揭示其空间变异的主要因素。结果表明:(1)随土层的加深,土壤饱和导水率逐渐增加,不同土层土壤饱和导水率的空间变异程度存在差异,表现为40—60 cm土层土壤饱和导水率为强变异,其他土层均为中等变异。(2)不同土层土壤饱和导水率的空间结构也存在差异,20—40,40—60,60—80 cm土层土壤饱和导水率表现为强烈的空间自相关性,0—20,80—100 cm土层土壤饱和导水率表现为中等空间自相关性。(3)坡面土壤饱和导水率与石砾含量、非毛管孔隙度、毛管持水量、田间持水量和毛管孔隙度显著相关。综上,研究坡面土壤饱和导水率具有较强的空间变异,石砾含量和土壤物理性质是影响研究坡面土壤饱和导水率空间分布的主要因素。

Spatial Heterogeneity of Soil Saturated Hydraulic Conductivity and Its Influencing Factors on a Larch Plantation Hillslope in Liupan Mountain

In order to deeply understand the spatial heterogeneity of soil saturated hydraulic conductivity along the forest hillslope, the classical statistical and geostatistical methods were used to study the spatial heterogeneity of soil saturated hydraulic conductivity in different soil layers on Larix principis-rupprechtii plantation hillslope in Liupan Mountain, and the main factors of its spatial variability were revealed based on correlation analysis. The results showed that with the deepening of the soil layer, the soil saturated hydraulic conductivity gradually increased, and the spatial variability of the soil saturated hydraulic conductivities in different soil layers were different, showing a strong variation in the 40—60 cm soil layer and moderate variation in other layers; the spatial structure of the soil saturated hydraulic conductivity varied in different soil layers, showing strong spatial autocorrelation in 20—40 cm, 40—60 cm, and 60—80 cm soil layers, and medium spatial autocorrelation in 0—20 cm and 80—100 cm soil layers; soil saturated hydraulic conductivity at slope scale was significantly correlated with rock fragment content, non-capillary porosity, capillary capacity, field capacity and capillary porosity. The soil saturated hydraulic conductivity along the studied hillslope has strong spatial variability, and rock fragment content and soil physical properties are the main factors affecting the spatial distribution of soil saturated hydraulic conductivity at slope scale.