长白山主要类型森林土壤大孔隙数量与垂直分布规律

利用张力入渗仪测量和计算了长白山自然保护区中4种主要类型土壤(暗棕色森林土、棕色针叶林土、山地生草森林土和山地苔原土)中半径范围分别在≥0.5mm、0.25～0.5mm和0.1～0.25mm的大孔隙数量与分布,并探讨了大孔隙的存在对土壤饱和渗水量的影响.结果表明:暗棕色森林土中大孔隙数量随土壤深度的增加而减少,自地表向下至40cm以内土层的变化较快,在40cm以下土层内的变化较慢;棕色针叶林土和山地苔原土中大孔隙数量随土壤深度的增加而增加;山地生草森林土中大孔隙数量随土壤深度的变化不大.大孔隙占土壤体积的比例虽然很小,却对土壤饱和渗水量的传导起到了重要作用.

Amount and vertical distribution of macropores in forest soils in Changbai Mountains

By using tension infiltrometer, this paper studied the amount and vertical distribution of macropores with the radius of > or = 0.5 mm, 0.25-0.5 mm and 0. 1-0. 25 mm in dark brown forest soil, brown coniferous forest soil, mountain soddy forest soil, and mountain tundra soil in Changbai Mountains, and the effects of these macropores on soil saturated flux. The results showed that in dark brown forest soil, the amount of macropores decreased with increasing soil depth, being faster from surface soil down to 40 cm deep and slower beneath the depth of 40 cm. In brown coniferous forest soil and mountain tundra soil, the amount of macropores increased with increasing soil depth; while in mountain soddy forest soil, there was a little change in the amount of macropores with soil depth. Though the macropores only occupied a small proportion to the soil volume, they still played an important role in the transfer of soil saturated flux.