Nutrient Status of Surface Soil of Cultivated Land in Guizhou

The content of organic matter,total N,available N,available p,rapidly available K,slowly available K and pH of 0.3958 million samples from surface soils of cultivated land in Guizhou during 2005~2012 were analyzed by using Excel and Spss statistic software according to the nutrient grading standard of second soil general survey to make fertilization schedule scientifically,utilize fertilizer resources rationally and improve utilization rate of cultivated land and fertilizer in Guizhou.The results showed that the average content of organic matter,total N,available N,available p,rapidly available K and slowly available K of surface soil of cultivated land was 35.52g/kg,1.97g/kg,158.65mg/kg,16.95 mg/kg,139.65mg/kg and 271.23mg/kg separately.The organic matter content of 30.78%soil samples was in very abundant grade.The total nitrogen content of 30.44% soil samples was in the optimum grade. The available nitrogen content of 35.17% and 31.13% soil samples was in the suitable grade and optimum grade separately.The available P of 34.51% soil samples and rapidly available K of 30.48% soil samples both were in the suitable grade.The slowly available K content of 26.86% soil samples and 25.26% soil samples was in the very deficiency grade and very abundant grade respectively.The corresponding fertilization suggestions for main food crops are put forward according to grading distribution status of soil nutrient content in different cities(prefectures),Guizhou.