Analysis on Evergreen Broad-Leaved Forest Soil Nutrients in Baotaishan Forest Park of Yongping County

Five different communities of evergreen broad-leaved forests in Baotaishan Forest Park of Yongping County were studied by analyzing the variation of organic matter and N,P,K contents in 0- 20 cm and 20- 40 cm soil layers in different communities. The results showed that the soil nutrient content was generally high under the natural vegetation in the study area,with medium variation,and only the available P content varied strongly. There were significant differences in organic matter content in 0- 20 cm soil layer among stands of Vaccinium bracteatum,Castanopsis orthacantha,Quercus castanopsis and Lithocarpus glaber( P 0. 05),and the organic matter content in0- 20cm soil layer was significantly higher than that of in the 20- 40 cm soil layer. There was no significant difference in total N and available N contents between the 0- 20 cm and 20- 40 cm soil layer. The variation trend of total P content agreed with that of the organic matter,the available P in the 0- 20 cm layer was higher than that of in the 20- 40 cm layer. The total K content increased with the soil depth,but there was just a little change. On the contrary to total K,the available K decreased along with the increase of soil depth. Among the 7 indices,only total N and available N contents were significantly correlated with soil organic matter content,indicating that P and K of the soil were not primarily derived from soil organic matter,which might be mainly derived from the maternal material of the soil.