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 0-20cm and 20-40cm 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 0-20cm soil layer among stands of Vaccinium bracteatum, Castanopsis orthacantha, Quercus castanopsis and Lithocarpus glaber(P<005), and the organic matter content in 0-20cm soil layer was significantly higher than that of in the 20-40cm soil layer. There was no significant difference in total N and available N contents between the 0-20cm and 20-40cm soil layer. The variation trend of total P content agreed with that of the organic matter, the available P in the 0-20cm layer was higher than that of in the 20-40cm 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 .