The Analysis of Spatial Experiments

Anyone with an interest in precision agriculture has already formed a hypothesis that the field is a sub-optimum management unit for cropping. The role of experimentation is to test this hypothesis. Geostatistics can play an important role in analysing experiments for site-specific crop management: put simply, spatial autocorrelation must be accounted for if one is to draw valid inferences. We provide here some background to the basic concepts of agronomic experimentation. We then consider two broad classes of experimental design for precision agriculture (management-class experiments and local-response experiments), and show, with the aid of case studies, how each may be analysed geostatistically. Ultimately though, if farmers are compelled to use relatively simple designs and less formal analyses, then researchers must follow and adapt their geostatistical analyses accordingly.

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