Charateristics of nutrient content in soil in uncaria origins from Guizhou

The soil nutrient differences for uncaria under different types of land utilization in Guizhou province were analyzed by field investigation and indoor analysis. Results indicated that the soil in three types of land utilization were strongly acid soil. The soil pH value, organic matter, total nitrogen and available nitrogen, available phosphorus content under different land utilization were natural forest land > grassland > uncaria base, uncaria base > grassland > natural forest land, grassland>uncaria base>natural forest land, respectively. In general, the soil nutrient of uncaria in Guizhou province was suitable. Significant negative correlations existed between pH value and organic matter, total nitrogen, available nitrogen, available P content, available K content. Significant negative correlations were found between total nitrogen and available nitrogen, between total nitrogen and available P content, between available nitrogen and available P content, between available nitrogen and available K content, available P content and available nitrogen content, available P and available K content. The research results can provide the theoretical basis for soil improvement in uncaria base and the cultivation techniques with high yield and good quality for uncaria.