[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.