Soil Erodibility K-Value of Semi-natural Forests in Northeast China

LI Xu;WANG Hai-yan;YANG Xiao-juan;LIU Ling;LI Wei-song;WANG Yue;School of Forestry,Beijing Forestry University;School of Soil and Water Conservation,Beijing Forestry University;

soil erodibility K-value;;erosion productivity impact calculator;;soil nutrients

The soil particle size distribution and soil nutrients contents in the soil depth of 0—20cm,20—40cm and40—60cm were analyzed,the soil sampling got from ten semi-natural forest plots in forest farms of Wangqing Forestry Bureau,Jilin Province.In addition,the soil erodibility K-value in this region was investigated with the formula calculation method of EPIC(erosion productivity impact calculator)and its affecting factors,the correlation between K-value and soil nutrients were discussed.The results indicated that the mean K-value was0.060 7t·hm2·h/(MJ·mm·hm2).The K-value at the soil depth of 0—20cm was higher than that at20—60cm.Higher K-values were found in coniferous and broad-leaved mixed forest than broad-leaved mixed forest.The K-value decreased with increasing stand density and canopy density when stand density was less than 1 200hm2 and canopy density less than 0.75.The correlations between K-value and soil nutrients were in a descending order of total nitrogen,readily available potassium,available phosphorus and total phosphorus in the study area.All soil nutrients were negatively correlated with K-value except total nitrogen.The optimal stand density was about 750~1 200trees/hm2 with higher soil nutrient concentrations and soil antierodibility.