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通过与第二次土壤普查剖面点相同位置采样、分析,运用地统计学方法,研究了禹城市耕层土壤有机质含量变化的空间分布,结果表明:研究区耕层土壤有机质含量普遍提高,增加幅度变化于-4.35gkg-1～32.53gkg-1,平均增加12.949gkg-1。土壤有机质含量变化的半变异函数可以球状、圆形、指数、高斯等模型表征,随机性因素如施肥、耕作措施、种植制度等各种人为活动是土壤耕层有机质含量变化空间分布的主要因素,土壤有机质含量增加的原因主要是秸秆还田面积增加、大量氮肥的使用;而增加幅度小甚至为负值的剖面主要是由潮湿变干燥、林地转为耕地所导致。
The spatial distribution of soil organic matter content in the topsoil of Yucheng City was studied by sampling, analyzing and using the geostatistics method at the same position with the second soil survey. The results showed that the content of organic matter in the topsoil of the study area generally increased, Change from -4.35gkg-1 to 32.53gkg-1, with an average increase of 12.949gkg-1. The semi-variogram of soil organic matter content can be characterized by spherical, circular, exponential and Gaussian models. The random factors such as fertilization, tillage and planting system are the main factors that affect the spatial distribution of soil organic matter content. The increase of soil organic matter content is mainly due to the increase of straw returning area and the use of a large amount of nitrogenous fertilizer. The increase of small or even negative value is mainly caused by the dampness drying and the conversion of forestland to arable land.