首页|期刊导航|中国农业科学(英文版)|Optimised Spatial Sampling Scheme for Soil Electriclal Conductivity Based on Variance Quad-Tree(VQT)Method
中国农业科学(英文版)2007，Vol.6Issue(12)：1463-1471,9.
Optimised Spatial Sampling Scheme for Soil Electriclal Conductivity Based on Variance Quad-Tree(VQT)Method
Optimised Spatial Sampling Scheme for Soil Electriclal Conductivity Based on Variance Quad-Tree(VQT)Method
摘要
Abstract
The acquisition of precise soil data representative of the entire survey area,is a critical issue for many treatments such as irrigation or fertilization in precision agriculture.The aim of this study was to investigate the spatial variability of soil bulk electrical conductivity(ECb)in a coastal saline field and design an optimized spatial sampling scheme of ECb based on a sampling design algorithm,the variance quad-tree(VQT)method.Soil ECb data were collected from the field at 20m interval in a regular grid scheme.The smooth contour map of the whole field was obtained by ordinary kriging interpolation,VQT algorithm was then used to split the smooth contour map into strata of different number desired,the sampling locations can be selected within each stratum in subsequent sampling.The result indicated that the probability of choosing representative sampling sites was increased significantly by using VQT method with the sampling number being greatly reduced compared to grid sampling design while retaining the same prediction accuracy.The advantage of the VQT method is that this scheme samples sparsely in fields where the spatial variability is relatively uniform and more intensive where the variability is large.Thus the sampling efficiency can be improved,hence facilitate an assessment methodology that can be applied in a rapid,practical and cost-effective manner.关键词
variance quad-tree(VQT)/sampling scheme/spatial variability/kriging interpolation/precision agricultureKey words
variance quad-tree(VQT)/sampling scheme/spatial variability/kriging interpolation/precision agriculture分类
农业科技引用本文复制引用
LI Yan,SHI Zhou,WU Ci-fang,LI Feng,LI Hong-yi..Optimised Spatial Sampling Scheme for Soil Electriclal Conductivity Based on Variance Quad-Tree(VQT)Method[J].中国农业科学(英文版),2007,6(12):1463-1471,9.基金项目
We thank the financial support from the National Natural Science Foundation of China(40701007,40571066) （40701007,40571066）
and the Postdoctoral Science Foundation of China (20060401048) （20060401048）
We also thank McBratney et al.(1999)for their original work to introduce the VQT method. （1999）
