两种人工林土壤物理性质时空变异性

Temporal and Spatial Variability of Soil Physical Properties of Two Artificial Forest Stands

运用经典统计学方法,对东北林业大学哈尔滨实验林场白桦(Betula platyphylla Suk.)和落叶松(Lar-ix gmelini Rupr.)人工林林地土壤物理性质时空异质性进行了研究。结果表明:两林地在垂直方向上土壤非毛管孔隙度和毛管孔隙度均值差异性不显著,而在时间序列上的变化则差异性显著,非毛管孔隙度变异性属于中等变异,毛管孔隙度变异属于弱变异,但其变异性不论在深度方向上还是在时间序列上均未达到显著水平;两林地总孔隙度均值随土层深度先增加后减小,但这一变化未达到显著水平,而在时间序列上总孔隙度的变化差异性显著,总孔隙度变异系数存在差异,但未达到显著水平,属于弱变异性;两林地土壤密度均值随土层深度先减小后增加,但差异未达到显著水平,在时间序列上土壤密度差异性显著,7、8、9月份较低,土壤密度变异属于弱变异,变异系数存在差异,但未达到显著水平;两林地毛管持水量和饱和持水量均值随土层深度先增加后减小,但差异未达到显著水平,在时间序列上差异性显著,呈季节性变化,毛管持水量和饱和持水量变异既有弱变异也有中等变异,变异系数存在差异,但均未达到显著水平。

An experiment was conducted to study the soil physical properties of two artificial forest stands （ Betula platyphylla and Larix gmelini） in Harbin Experimental Forest Farm of Northeast Forestry University using classical statistical methods. An insignificant difference in non-capillary porosity and capillary porosity in the depth direction was observed between the two stands, while a significant difference was found in time series. The variability of non-capillary porosity was medium, and that of capillary porosity was weak, but the difference in variability was insignificant either in the depth direction or in time series. The total porosity first increased and then decreased with increasing depth with an insignificant difference, while a significant difference was observed in time series. The coefficients of variation of total porosity in the two stands were different with an unobvious difference, belonging to a weak variability. The soil bulk density first decreased and then increased with increasing depth with an insignificant difference in variability, while there was a significant difference in time series （ lower in July, August and September）. The coefficients of variation of soil bulk density were different with an insignificant difference, belonging to weak variability. The capillary water capacity and saturation moisture capacity first increased and then decreased with increasing depth with an insignificant difference in variability, while they varied with season and exhibited a significant difference in time series. The eoeflqeients of variation of capillary water capacity and saturation moisture capacity were different with an insignificant difference, belonging to weak or medium variability.