耕地养分空间插值技术与合理采样密度的比较研究

Comparison of Spatial Interpolation Technique of Soil Nutrient and Reasonable Sampling Density

土壤养分连续空间分布数据是土壤信息系统工作的基础,土壤养分空间插值的研究因此变得尤为重要。对湖北省鄂州市进行土壤养分采样调查,以对作物生长作用较为密切的有效氮、有效磷、有效钾、pH为研究对象,运用克里格法(Kriging)、样条函数法(Spline)、距离权重倒数法(IDW)3种插值方法对数据进行栅格化处理,分析比较3种插值方法所得结果的特性以及对耕地养分数据插值的适宜性。通过调整空间采样点密度,比较几种空间采样密度对插值结果的影响,总结3种插值方法在不同空间尺度下的插值精度,并在不同土壤类型内进行不同采样密度的插值分析。

The data of soil nutrients, which are distributing in series, are the foundation for soil information system, hence research on spatial interpolation becomes more important. We investigated some available soil nutrients including N, P, and K and pH, which are all well related to crop growth in E＇Zhou of HuBei province. The data was turned into grid by different interpolation methods including Kriging, Spline and IDW. We compared the results of the three interpolation methods and analyzed which method is the best for the management of soil nutrients. By changing spatial sampling density, we compared the interpolation results in different spatial scales, and then summed up the interpolation precision by using he three interpolation methods. Finally, interpolation analysis on different agro types of different sampling density was conducted.