丘陵地区植烟土壤有机质空间变异研究——以重庆市彭水县为例

Spatial Variability of Soil Organic Matter Content in Tobacco Planting Regions of Hilly Area——A Case Study in Pengshui County of Chongqing

以重庆市彭水县为例,采用传统统计学和地统计学方法研究了丘陵地区植烟土壤有机质的空间变异特征.传统统计分析结果表明:研究区域内土壤有机质含量平均为26.99 g/kg,变异系数为0.33,属于中等变异强度.比较了不同趋势效应下普通Kriging法的插值误差,结果表明应考虑有机质分布的各向异性和二阶趋势效应.在此基础上采用普通Kriging插值法得到该区土壤有机质含量的变异特征,其变异主要发生在西南到东北方向,这与该地区的地形和人为活动有密切关系.

Traditional statistics combined with Geostatistics was applied to analyze the spatial variability of soil organic matter content in tobacco planting regions of three gorges reservoir. Traditional statistical analyses showed the mean and coefficient of variation of SOM content were 26.99g kg^-1 and 0.33, respectively. The results indicated that its distribution was moderately variable in this region. By ordinary Kriging spatial interpolation, the integrative comparison of the prediction errors from the trend effects of 0, 1 and 2 order indicated that the 2-order trend effect was preferable and the spatial variation of SOM content was anisotropic. The Kriging spatial interpolation showed that SOM increased gradually from the southwest to northeast and also from the northeast to southwest and the highest level band of SOM content was in the middle part of Pengshui county. The spatial distribution of SOM content was related to variation in topog- raphy and anthropogenic activities.