Studies of Relations between Soil Organic Matter Content and Soil Bulk Density in Different Soil Level in Donglan County

Using chestnuts in A and B level of the soil profiles in 7 kind of site types of the forest land returned from the cultivated land and wasteland woodland in Donglan County as studying objects, the blade ring method was used to survey soil bulk density, the potassium dichromate-outside the heating method was used to survey soil organic matter content, the analysis of variance with single factor was used to analyze the differences of A and B level of soil organic matter content and soil bulk density, the analysis of Least-squares was used to estimate the regression equation of soil organic matter content and soil bulk density. The relations of regression equation of quadratic parabola was obtained in A level between soil organic matter content and soil bulk density. The relations of regression equation of three parabolic was obtained in B level between soil organic matter content and soil bulk density. The extent of A level between soil organic matter content and soil bulk density was deeper than that of the B level. The extent of A level and B level between soil organic matter content and soil bulk density in the wasteland woodland was deeper than that of A and B level of the forest land returned from the cultivated land.