Mapping and interpreting the yield variation in cereal crops

The existence of spatial variability within fields points to considerable benefits if inputs to arable crop production are targeted according to locally determined requirement. The paper discusses yield mapping as a data source on variability and emphasises the need to integrate data on all sources of spatial variability with the management/agronomic expertise of the farmer to develop an application strategy for field inputs. A yield mapping system is described and examples of yield maps from one field in four successive years, together with data on soil spatial variability are presented. An exploratory study was made of appropriate statistical techniques to compare yield maps analytically. Consistency of yield variation in the test field from season to season and correlation with a limited sampling of soil nutrient parameters were low. However, significant correlation between soil series and yield was observed.