湘西植烟土壤pH状况及空间分布研究

为了解湘西州植烟土壤pH分布状况，测试了湘西州主要烟区488个土壤样本，采用传统统计学和地统计学方法分析了湘西州植烟土壤pH适宜样本分布、县域差异、土壤类型差异、海拔差异及空间分布。结果表明：（1）湘西州植烟土壤pH总体适宜，平均为5.87，变异系数为11.13%；pH处于适宜烤烟生长的5.5~7.0间的土壤样本占72.75%。（2）湘西州主产烟县植烟土壤pH大小表现为：保靖县＞龙山县＞芦溪县＞凤凰县＞花垣县＞永顺县＞古丈县。（3）湘西州烟区不同土壤类型pH大小表现为：灰黄棕土＞石灰土＞灰黄泥＞灰黄土＞黄壤＞红壤＞浅灰黄泥＞水稻土。（4）湘西州植烟土壤pH有随海拔升高而升高的趋势。（5）植烟土壤pH Kriging插值图显示，湘西州植烟土壤pH呈斑块状分布态势，在保靖县、龙山县和永顺县的部分地区各有一个高值区，在古丈县的中部有一个低值区。

Spatial Distribution and pH Condition of Tobacco-growing Soil in Xiangxi

In order to understand the distribution of pH in tobacco growing soils of Xiangxi,distribution frequency of pH value,difference of different county,difference of different soil types,difference of different altitude and Spatial distribution of tobacco-growing soil pH value were analyzed by collecting 488 soil samples.The results were as follows：（1） The soil pH in the tobacco soil was generally suitable for tobacco cultivation,with a spatial mean of 5.87 and variation coefficient of 11.13%.About 72.75% of the soil samples had pH between 5.5-7.0 most suitable for high quality tobacco cultivation.（2） The soil pH for different counties of Xiangxi tobacco lands was in the following order： Baojing Longshan Luxi Fenguang Huayuan Yongshun Guzhang.（3）The soil pH for different soil types was in the following order too： yellow-brown ash soil rendzina soil yellow ash mud yellow ash soil yellow soil red soil light yellow ash mud paddy soil.（4） The soil pH value was increasing with the rise of altitude in tobacco growing soils of Xiangxi.（5） The unobserved points of tobacco growing soils of Xiangxi were estimated and the contour map was obtained using the Kriging method.The results indicated that the spatial distributions of the soil pH value were plaque.The high value area of the soil pH value was in some areas of Baojing,Longshan,Yongshun,respectively.The low value area of the soil pH value was in some areas of Guzhang.