Comprehensive Evaluation And Variation Analysis Of Fertility Of Tobacco-growing Soil In Eshan County Of Yunnan Province

The soils in sampling sites of tobacco growing area in Eshan county of Yunnan Province were serially sampled respectively in2008and2012, and comprehensive evaluation was conducted on the spatial and temporal variations of soil fertility. The results showed that:1、the pH values of soil in Eshan, Yunnan were in a range of4.03-8.29, the contents of organic matter in a range of1.7-71.9g/kg, available N in a range of15-293mg/kg, and the suitability proportion was88.84%; the contents of available P and available K were lower than70%, slightly less than the average. available Zn in a range of0.23-20.97mg/kg, and the suitability proportion was97.31%;2、The average of comprehensive evaluation indexes of tobacco-growing soil was0.63, the coefficient of variation was1.4%, the fertility was evenly distributed and the spatial variation was small. The fertility of tobacco-growing soil in Eshan was divided into higher, high, medium, low and lower grades according to the IFI value. The proportion of area with soil fertility above the medium grade was85.96%, the soil fertility in tobacco-growing area of Shuangjiangzhen and Fuliangpeng were higher compared to other towns.3、Compared to2008, the pH value of tobacco-growing soil decreased by0.22, the contents of organic matter reduced by0.44g/kg, the amount of available N increased by4.21mg/kg, the amount of available P decreased by0.14mg/kg, available K increased by21.88mg/kg, trace element Zn increased by0.76mg/kg and soil comprehensive fertility indexes increased by0.08in2012.