Analysis and Assessment of Nutrients in Tobacco Growing Soil Around Shennongjia Areas

The pH values of and contents of organic matter and nutrients in more than 1700 topsoil samples from areas around Shennongjia were analyzed by way of investigation,collection and sample analysis,the results showed that the ranges of pH values of and contents of organic matter and available N,P and K in tobacco growing soil were 5.02-7.92,11.19-52.24 g/kg,58.69-216.20 mg/kg,3.92-39.00 mg/kg and 51.84-332.14 mg/kg,respectively,with the least and largest CV for pH and available P,respectively.The samples with pH value of 5.5-7.5 suitable for tobacco growth accounted for 82.5%.General speaking,the contents of organic matter and available N in soil were relatively higher,while those of available P and K were relatively lower.In point of the output value of flue-cured tobacco,the soil in most of the areas is rich or moderate in N supplying,and moderate or short in P and K supplying.K is obviously regionally distributed,while N and P are not.