RIDGE TILLAGE EFFECTS ON SIMULATED WATER AND HEAT-TRANSPORT

Ridged soil surface configurations are often used as a management tool to improve the plant root environment. Possible benefits for ridge tillage systems include warmer and dryer seed-zone soil conditions in the spring, better control of wheel-traffic patterns, and better crop residue management for erosion control. This study compared soil physical properties in the plant row, the untracked interrow, and the wheel-tracked interrow positions for a ridge tillage system on three soils. Soil property information was used to model the effects of soil variability and ridge height on subsurface water and heat transport. Simulated water and heat flow in a ridge seemed to be different from that of a flat surface. Taller ridges had a greater influence on water and heat movement than shorter ridges. There seems to be an optimum ridge height for fastest warming and drying. Variable soil properties affected predicted soil temperature distributions less than predicted matric potential distributions. The compacted zone had a lower matric potential deep in the profile and a higher matric potential near the surface than the uncompacted zone. © 1990.