三门峡烟区土壤pH时空变异特征

Temporal and Spatial Variability of Soil pH in Sanmenxia Tobacco Area

利用地统计学方法结合GIS空间分析技术,对三门峡烟区土壤耕层(0～20cm)pH时间和空间变异特征进行了研究。结果表明,三门峡烟区pH在6.5～8.8之间变动,能够满足优质烟生产需要,但局部地区pH较高。pH服从对数正态分布,2002和2007年变异系数分别为15.2%和4.5%,变异函数的最佳理论模型为指数模型。土壤pH具有强烈的空间相关性,2002和2007年的变程分别为55.77km和92.39km。采用Kriging最优内插法得到三门峡烟区2002和2007年土壤pH空间分布图和差异图,并分析了土壤pH升高的原因和土壤改良措施。

Geostatistics with GIS spatial technology was applied to analyze the temporal and spatial variability of pH in top soil（0-20 cm） for tobacco planting region in Sanmenxia,Henan province.The results indicated that soil pH value ranged form 6.5 to 8.8 and met the requirement to produce high quality tobacco leave,but the pH value in some locations was a little high.The distribution of pH value was logarithm normal distribution,its variance coefficient was 15.2% and 4.5% for 2002 and 2007,respectively.The semivariogram of pH could be best described by the exponential model and spatial heterogeneity of pH was 55.77 km and 92.39 km.The Kriging interpolation method was applied to calculate the unobserved points and was used to generate the spatial and discrepancy map.The reasons that soil pH increased were analyzed and the strategies for soil improvement were also proposed.