Author
Lindstrom, Michael | |
SCHUMACHER, T - SOUTH DAKOTA STATE UNIV. | |
SCHUMACHER, J - SOUTH DAKOTA STATE UNIV. |
Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 7/10/1998 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: Soil translocation by tillage has been shown to result in soil erosion rates that exceed acceptable soil loss tolerance levels on convex hillslope positions with subsequent soil deposition in concave hillslope positions. This study was initiated to describe soil redistribution rates from tillage as affected by slope gradient and the rate of soil loss or deposition due to changes in slope gradients over representative landscape positions. Analysis consists of computer simulations showing changes in surface elevation based on previously determined soil movement rates by slope gradients in the direction of tillage for individual hillslope segments with the dimensions of 1 m by 1 m. Results from these simulations show that total soil translocation or movement down slope is governed by the maximum slope gradient of the backslope regardless of the configuration of upslope positions. The rate of translocation increases as slope gradients increase. The magnitude of soil loss or deposition at any place on the hillslope is governed by the variation in slope gradients between adjacent hillslope segments in the direction of soil thrust. On abruptly changing slopes with a difference in slope gradients of 1.5 percentage points, soil erosion will equal 49.5 t ha**-1. Soil translocation by tillage will result in variations in soil properties across field landscape positions that produce long-term changes in soil productivity. One consequence of soil translocation by tillage will be an increase in spatial variability of crop production and a likely decline in overall soil productivity. |