Abstract:

The research studied the theoretical basis of management of fertilizer in the forests of farmland returned in Donglan Country in Guangxi. The soil profiles were established by the typical sampling method, and soil samples were collected from layer A and B in soil respectively. Soil organic matter content was determined by potassium dichromate, the soil available nitrogen was determined by alkali diffusion method, the author compared the difference of soil organic matter and available nitrogen between Layer A and B in each sites by rating methods and analysis of variance. The results showed that the magnificent difference for soil organic matter and available nitrogen exist between layer A and B in 7 sites. The influence of soil organic matter content on the distribution of available nitrogen was a significant positive correlation in layer A. The soil organic matter content had no magnificent influence on the distribution of available nitrogen in layer B. There was less soil organic matter and available nitrogen in layer B. Deep-root plants could be fertilized with more manure or inorganic nitrogen.