Selection and Evaluation Method for Agriculture Experiment Field Base on Geostatistics

Experiment field is a basic condition for agriculture experiment,and the spatial heterogeneity of soil nutrient is the main factor causing experiment errors.So it is of great importance to select a field whose spatial distribution of soil nutrient is relatively uniform for reducing experiment errors and eventually ensuring the success of field experiment.In this study,the experiment field was selected by geostatistics method,an evaluation method of soil nutrient spatial variability was established to evaluate the spatial variability of soil nutrient,and a field experiment with the design of orthogonal regression was performed to test the selection method of agricultural experiment field and the evaluation method of soil spatial heterogeneity.The results showed that the rate of spatial variability of available N,available K,total N,total P,total K contents and pH value were all less than 20%,and their area rate of relative uniformity were 100%,which showed the spatial distribution of these soil nutrients were relatively uniform.The rate of spatial variability of available P and organic matter were all larger than 20%,but their area rates of relative uniformity were all larger than 80%(91.34% and 95.70% respectively), which also showed that the spatial distribution of the two soil nutrients were relatively uniform.Though the spatial distribution of soil nutrient was not absolutely uniform,the spatial variability was not significant,and the fields' fertility was relatively uniform.The experiment results of orthogonal regression design also indicated that the selecting way for experiment field and the evaluation method for soil nutrient spatial variability based on geostatistics are reasonable.