Abstract:
The soil nutrient contents of 188 tobacco-planting fields in Liuyang of Hunan were surveyed in 2000 and 2015 in order to instruct fertilization. The soil fertility suitability in 2015 was comprehensively evaluated, and the variations of soil nutrient contents from 2000 to 2015 were studied. The results showed that: 1) From 2000 to 2015, soil pH increased by 0.32 unit. Available P and available K increased by 118.84% and 63.42%. Organic matter and hydrolytic N reduced by 9.26% and 7.26%. Water-soluble Cl and available S decreased sharply by 55.87% and 24.33%. Except available Cu and Mo, all the other microelements increased. The average IFI of soil fertility changed from 0.536 to 0.650, increased by 21.27%. 2) Currently the soil pH and organic matter were relatively low. Available P, Cu and Fe were high while available Mo and water-soluble Cl were deficient. Other nutrient contents were appropriate. IFI of 75.76% tobacco-growing areas in Liuyang were high (75.76%) and 21.21% were medium. The difference in IFI was insignificant between different base units. The reasonable fertilization is to stabilize N, control P, and to increase K, Mo, Cl and organic manure fertilizers.