岩溶区植烟土壤pH、有效铁锰和交换性钙的空间异质性——以重庆市酉阳县为例

本研究通过野外调查，结合经典统计学和地统计学方法，分析了重庆市酉阳植烟区土壤表层pH、有效Fe、有效 Mn 和交换性 Ca 的空间异质性及相关性特征，以为岩溶区植烟土壤改良和平衡施肥以及特色优质烟叶开发提供理论依据。结果表明：酉阳植烟区土壤总体呈酸性，有效Fe、有效Mn和交换性Ca含量丰富；pH、有效Fe、有效Mn和交换性Ca变异系数为12.10%~47.86%，属于中等变异性，在土壤中比较稳定，块金效应在5.690%~7.338%，具有很强的空间相关性；pH和交换性Ca的空间分布为西高东低，有效Fe空间分布为东高西低，中部往西南方向含量最丰富，有效Mn的空间分布大致为中间低、四周高的趋势；pH与有效Fe、有效Mn存在显著的负相关性，pH与交换性Ca存在显著的正相关性。总之，研究区营养元素空间变异性中等，空间相关性强。

Spatial Heterogeneity of Soil pH, Available Fe, Available Mn and Exchangeable Ca in Tobacco-growing Soils in Karst Area: A Case Study of Youyang County, Chongqing

To provide a theoretical basis for the karst area of tobacco soil improvement and balanced fertilization and development characteristics of high-quality tobacco. This study based on field surveys and combined with classical statistical and geostatistical methods to analyze the spatial heterogeneity and correlation characteristics of surface soil pH, available iron, available manganese and exchangeable calcium of tobacco-growing area in Youyang Chongqing. The results showed that the soil pH was generally acidic and the available iron, available manganese and exchangeable calcium content were rich in the tobacco-growing area. The pH, available iron, available manganese and exchangeable calcium belonging to middle variation and were relatively stable in the soil with variation coefficient between 5.690~7.338%. The nugget effect of them were between 5.690~ 7.338%, with strong spatial correlation sex. The spatial distribution of pH and exchangeable calcium were high in the west and low in the east. The spatial distribution of available iron was high in the east and low in the west. The most content-rich was in the central to the southwest. The spatial distribution of available manganese generally was low in the middle, but high by surround. There was a significant negative correlation between pH and available iron, available manganese and exchangeable calcium. There was a significant positive correlation pH and exchangeable calcium. Overall, the nutrients element belonged to middle spatial variability, and had strong spatial correlation in the study area.