鲁中石质山地不同林分类型土壤结构特征

Structural Property of Soil from Different Forest Types on Rocky Mountainous Area in Middle of Shandong Province

运用土壤粒径质量分布原理与分形理论,对淄川峨庄流域内7种林分和对照荒草地的土壤结构特征进行研究。结果表明:①各种林分的土壤结构明显好于荒草地,不同林分类型中混交林分明显优于单纯林。良好的林分结构能明显提高土壤粒径的分布均匀程度与范围,改善土壤孔隙状况;②分形维数和重量平均直径能比较客观地表征土壤结构特征,是较为理想的土壤结构测定指标。混交林分分形维数均低于单纯林与荒草地,土壤重量平均直径均高于单纯林与荒草坡,说明混交林土壤结构稳定性最好,土壤通透性较好,具有较高的水土保持功能;③不同林分类型之间,土壤总孔隙度与非毛管孔隙度差异较大,而毛管孔隙度的差别较小。表明具有良好结构的林分,可有效改善土壤非毛管孔隙度和滞留贮水功能,从而有效地提高对降雨的快速贮存以及蓄洪与涵养水源作用。

According to the soil particle distribution theory and the fractal theory, this paper studied soil structural property of seven different forest types and grassland. The results showed that ： ① the soil structure of forest was better than grassland, and the mixed forest was superior to the pure forest. A good forest structure could improve the even degree and range of distribution obviously, and improve the porosity; ② the fractal dimension （FD） and mean weight diameter （MWD） could sign the soil structure feature objectively. The fractal dimension of the mixed forests were lower than the pure forests and grassland, and the soil weight diameter of the mixed forests were higher than the pure forests and grassland, which indicated that the mixed forest had best soil structure property in stability infiltration and water-holding; ③ the soil total porosity and the soil noncapillary porosity were different greatly between forest types, but the soil capillary porosity had little differ. It was showed that forest with good structure could improve the soil noncapillary porosity and water conversation function, and it was implied that forest with rational structure stored rainfall and surface runoff quickly.