Modeling tillage-induced morphological features in cultivated landscapes

Abstract

Previous tillage erosion models have generally assumed that tillage operations (over time) are conducted equally in opposite directions across the field. In reality, actual tillage patterns used by farmers are often much more complicated than this. However, to date, no research has been conducted to examine the impact of complex tillage patterns on tillage erosion. In this study, a Directional Tillage Erosion Model (DirTillEM) was developed to better account for the effect of complex tillage patterns and field boundaries on tillage erosion across an agricultural landscape. The DirTillEM was used on a hypothetical, completely level landscape (to negate the influence of topography) using tillage patterns typical of those used in the North American Prairies. The DirTillEM predictions agreed well with Light Detection and Ranging (LiDAR) topographic data collected from the near-level landscapes of the Red River Valley in Manitoba, Canada. Overall, the model predicted that tillage direction (especially when conducted repeatedly in specific patterns over many years) and field boundaries play a very important role in the creation and destruction of morphological features across the landscape – even in near-level landscapes which were previously thought to be less susceptible to the negative effects of tillage erosion. With the increased knowledge of processes involved in tillage translocation and tillage erosion, it is possible to avoid the undesired formation of morphological features within a field.