Soil chemical properties at burnt forest sites in Liaoheyuan Nature Reserve in North Hebei Provinc

Effects of soil depth (>0~5cm,>5~10cm,>10~20cm), burning intensity (not burned, slightly burned, moderately burned, severely burned, extremely burned)on soil chemical properties at burned Pinu stabulaeform is forest sites in Liaoheyuan Nature Reserve in North Hebei Province were investigated, to provide some theoretical basis for iprovement of burned soil and restoration of Pinus tabulaeformis forest . It was found that the soil pH had increased one year after the incident .The organic C, total N and total K also increasead after the fire, but such contents rather decreased under extremely burned condition. Panda vailable P in the burned soil also increased. In examination of verticald is tribution,soil pH, organic C, total N,total K,total Pand avail able P were all larger in surfaces oil than deep soil.Fire therefore has great impact on the chemical properties of surface soil,measured fire intensity could effectively improve soil fertility.