A comparative study on soil aggregate in Larch and Larch—Walnut forests

Abstract

According to the study on soils under the 34-year-old Larch forest and Larch-Walnut mixed forest, It was concluded that, in mixed forest, the total content of water-stable aggregate (0.25–5mm) in the upper layers (0–30cm) of soil was significantly higher than that in pure forest. The 2mm aggregates increased 48% in mixed forest soil compared with pure forest, and consequently, the three-phase ratio of soil was regulated, the physical properties improved and the fertility of soil raised. Because of the stability of total aggregate content and the importance of 2mm aggregate content in soil fertility, it’s advisable using the two indices above to characterize the effect of mixed forest on soil improvement.