Abstract: | Based on the two long-term experiments on red soil in hilly areas in the southern part of Hunan Province, a study on rehabilitation of natural vegetation in this area has been carried out.The results showed that when the more frequently vegetation was cut, the less bio-mass and the fewer the species of the vegetation were year by year, especially the growth of xylophyto. For example,in plot 1 (under annual cutting), the bio-mass of vegetation decreased from 90. 2kg/plot to 45. 0kg/polt, the species of the vegetation decreased from 15 to 4, and the proportion of the xylophyta biomass decreased from 17% to 0.9% in 1991. As for imparata cylindrica var. major during the process of restoration of natural vegetation, applying fertilizer made it reproduced excessively, then eliminate. With frequently cutting, the soil fertility was exhausted gradually and the biomass of Imparata cylindrica decreased sharply, especially under the condition of N fertilizer application. |