Soil Survey Grain Productivity and Productivity Risk Assessment with Yield Map Data.

Yield monitors and computational tools have improved our capability to assess the impact of soil-landscape and climate variability on grain yield and yield risk. The objective of our study is to generate productivity information for use in soil survey applications and to calibrate a soil productivity index using a large regional database of grain yield maps. Initial findings show that yield variation within soil map-units and between years is large due to changing spatial patterns in yield between wet and dry years. The relationship with a soil productivity index also changes year to year. This strategy used in this research can provide more up-to-date assessment of productivity potential and productivity risk for soil survey products.