湘西植烟土壤有效铁含量及变化规律研究

为探明湘西州植烟土壤有效铁含量的分布状况,检测了湘西州主要烟区488个土壤样本的有效铁含量,并采用传统统计学和地统计学方法分析了湘西州植烟土壤有效铁含量适宜样本分布、县域差异、土壤类型差异、海拔高度差异及空间分布。结果表明：①湘西州植烟土壤有效铁含量总体水平高,平均值83.20 mg/kg,变幅10.04～328.89 mg/kg,变异系数82.31%。②不同县之间的植烟土壤有效铁含量差异不显著,从大到小依次为：泸溪县、凤凰县、花垣县、古丈县、永顺县、龙山县、保靖县。③不同土壤类型土壤有效铁含量差异极显著,从高到低依次为：红灰土、石灰土、红壤、黄壤、水稻土、黄棕壤。④不同海拔高度的植烟土壤有效铁含量差异不显著,5个海拔高度组的植烟土壤有效铁含量平均为62.00～192.00 mg/kg。⑤植烟土壤有效铁含量Kriging插值图显示,湘西州植烟土壤有效铁含量总体上呈斑块状分布态势,以有效铁含量89.9～184.0 mg/kg为主要分布面积,主要分布在湘西州的南部和北部地区。

Content and Change of Available Iron in Tobacco-growing Soil from Xiangxi Autonomous Prefecture

In order to understand the distribution of available iron contents in tobacco growing soils of Xiangxi,distribution frequency of available iron contents among different counties,soil types,altitudes were analyzed by both classic statistics and geostatistics with 488 soil samples.The results were as follows：（1） Available iron contents in the tobacco soils were little higher with a mean of 83.20 mg / kg,amplitude of 10.04 ～ 328.89 mg / kg and variation coefficient of 82.31%.About 27.10% of the soil samples of available iron contents were suitable for tobacco cultivation.（2） There were no significant differences among the different counties for the contents of available iron,and the order of available iron content in soil for different counties was Luxi Fenghuang Huayuan Guzhang Yongshun Longshan Baojing.（3） There were extremely significant differences among different soil types for the contents of available iron,and the order of available iron content in soil for different soil types was red ash soil lime soil red soil yellow soil paddy field yellow brown soil.（4） There were no significant differences among the different altitudes for the contents of available iron,and its content in average of 61.68 ～ 91.84 mg / kg in five groups.（5） Kriging interpolation map indicated that the spatial distributions of available iron were plaques shape distribution and its main area are exist in the northern and southern that available iron content is 89.9 ～ 184.0 mg / kg.