Wheel traffic considerations in erosion research

R ECENT field experiments in Minnesota showed that wheel traffic from farming operations may compact the soil to a depth of 300 mm or more. This compaction can persist despite tillage, freezing and thawing. Thus, bulk density, aggregate size and stability, random roughness of the soil surface, infiltration rate, and other erosion-related soil properties are changed. This can cause concentrated areas of different soil properties and drastically alter erosion on research plots. Effects of wheel traffic could bias the erosion results of the actual treatment under investigation. This paper describes how wheel-induced compaction may alter erosion results