以关帝山华北落叶松林下土壤为研究对象,选择采伐干扰样地A(人工间伐)和未采伐干扰样地B,采用地统计学小支撑、多样点的布点采样设计;用根钻法(直径φ=7.0 cm)分别采取0～10、10～20、20～30 cm三层土壤样品.分析测定了土壤含水量、pH和全氮含量,采用传统统计和地统计学变异函数相结合的方法进行数据分析.结果表明:(1)采伐干扰样地A,土壤含水量降低,土壤含水量的变异减小.0～10 cm土层,未采伐干扰样地B,土壤含水量呈现强的异质性(C0+C=12.12),空间变异特征较复杂(分维数D=1.944);采伐干扰样地A异质性程度降低(C0+C=10.39),在较小尺度(0.5～12.9 m)上表现出空间自相关变异.(2)未采伐干扰样地B土壤pH为6.69,采伐干扰样地A土壤pH升高(6.86);采伐后土壤pH空间自相关变异减少,随机性变异增强.(3)未采伐干扰样地B土壤全氮含量(0～30 cm)均值为0.106g kg-1,采伐干扰样地A(0.022 gkg-1)土壤全氮含量显著降低.未采伐干扰样地B土壤全氮的空间异质性特征明显,主要呈现较小尺度的空间自相关变异;采伐干扰样地A土壤全氮异质性强度明显降低,而空间变异尺度加大.土壤含水量、pH和全氮含量空间异质性的垂直分异均表现为随土层深度的增加而减小.%This study was conducted in Larix principis-rupprechtii forests, located in GuanDi Mountain, Shanxi Province, China. Two plots (32m × 32m) were selected which represented disturbed stand (plot A) and undisturbed( plot B) respectively. Based on theory and methodology of spatial pattern analysis in geostatistics, samples were taken at three soil depths (0 ～ 10cm, 10 ～ 20cm and 20 ～ 30cm. ) using soil core (7. 0cm in diameter) . The spatial heterogeneity of soil characteristics (soil moisture , pH ,total N)was analyzed. The result showed that soil moisture and its spatial heterogeneity decreased in disturbed stand, remained mainly spatial variation at small scales. Harvesting increased the means of soil pH (pH = 6. 86, plot A). Compared with soil pH at same soil depth in different stand, the proportion of randomly variation increased in disturbed stand and spatial autocorrelation variation became weaker. After cutting disturbance, the soil total nitrogen decreased significantly. Semivariogram analysis demonstrated that harvesting modified spatial pattern of soil total nitrogen , the spatial heterogeneity decreased at large scales. The spatial heterogeneity intensity of soil moisture, pH and total nitrogen became lower along with increase of soil depths.
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