Distribution of Available Boron Contents of Tobacco-growing Soil and Its Influencing Factors in Karst Region——A Case of Tobacco-growing Areas in Xiangxi

The available boron contents in tobacco growing soils and its influencing factors in Xiangxi were analyzed by collected 488 soil samples. The results were as follows: 1) available boron contents in the tobacco soils were slight higher for tobacco cultivation, it ranged from 0.05 to 2.21 mg/kg with a mean of 0.728 mg/kg and a variation coefficient of 53.46%, about 30.00% of the soil samples with available boron content were suitable for tobacco cultivation. 2) IDW interpolation map indicated that the spatial distributions of available boron were patchiness, while the high value area were in the eastern part of Yongshun and the low value area were in the western part of Yongshun. 3) The available boron contents of soils following vegetable and rape crop were higher than the other, and the average content of available boron in yellow-brown soil was higher than red lime soil and red soil. 4) The available boron contents was increased with the rise of altitude, pH and organic matter content in tobacco growing soil of Xiangxi.