Study On The Spatial Pattern Of Available K In Grapery In Shaanxi Guanzhong | 陕西关中葡萄园土壤有效钾空间格局研究

Chinese. 探讨陕西关中葡萄园土壤有效钾空间变异及其分布格局，为葡萄园精确施肥提供参考依据。以陕西关中葡萄园为研究区，用网格法（50 m×50 m）采集土样46个，应用ArcGIS Geostatistics模块对土壤有效钾含量进行地统计分析和Kriging插值分析。研究区土壤有效钾含量为70.4~172.0 mg/kg，平均113.0 mg/kg，符合正态分布。有效钾含量在南北方向呈明显的南低北高趋势，可用二阶曲线拟合。土壤有效钾的最佳半方差函数符合球状模型，且具有明显的各向异性特征，长轴方向的变程是短轴方向的4.2倍，表现出强烈的空间相关性。研究区有效钾含量分布表现出较明显的中间高、四周低的阶梯状分布趋势，这种分布状况与当地的地势分布基本一致。结构性因素对研究区土壤有效钾含量的空间变异起主导作用。

English. The objective of this study was to explore the spatial variability and distribution of available K in soil to provide a solid foundation for scientifically formulated fertilizer. Geostatistics module of ArcGIS was applied to study the spatial variability and distribution of available K in soil based on the data of 46 soil samples taken by grid sampling method (50 m×50 m ) in grapery in Shaanxi Guanzhong as the case study. The available K content followed a normal distribution, with an average 113.0 mg/kg and a range from 70.4 mg/kg to 172.0 mg/kg in the study area. The distribution of available K content in the whole area exhibited a second-order trend (north higher than south). The best theoretical model was spherical one, with an anisotropy. The spatial autocorrelation distances (ranges) in long axle was 4.2 times of the short axle, and spatial autocorrelation was strong. A spatial distribution map of available K content was higher in center than in brink with a ladder-like distribution trends. The spatial variability of available K content in the study area was fundamentally operated by structural factors. On the other side, man-made factors (fertilization and the build-time of grapery) also took some influence on the distribution of available K content.