Using fallout Cesium-137 to understand soil redistribution over agricultural landscapes

Authors: Ritchie, Jerry; McCarty, Gregory

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 1/7/2008
Publication Date: 3/15/2008
Citation: Ritchie, J.C., McCarty, G.W. 2008. Using fallout Cesium-137 to understand soil redistribution over agricultural landscapes [abstracts]. Abstracts of the 15th International Congress of the International Soil Conservation Organization (ISCO). p. 63.

Interpretive Summary:

Technical Abstract: While it is recognized that soil erosion is highly variable in space and time, studies of the redistribution of soil within a field or watershed are limited. Our studies focus on the use of fallout Cesium-137 to understand pattern of soil movement on the landscape. It is often assumed that eroding soils results in soil losses from agricultural fields; however, our studies indicate that most of the eroding soils are subsequent redeposited within same field. These studies also investigated the relationship between soil redistribution and soil organic carbon (SOC) patterns in agricultural fields. Cesium-137, soil redistribution, and SOC redistribution in agricultural fields were significantly correlated. Hillslope areas had significantly more soil and SOC loss than soils in toe slope positions (deposition). Soil erosion increased as gradient slope increases and soils on concave slopes had higher SOC than soils on convex slopes. These data suggest that soil redistribution patterns and topographic patterns can be used to help understand soil erosion and SOC redistribution patterns on agricultural landscapes. The strong significant relationships between the patterns of soil and SOC redistribution patterns in agricultural soils suggest that they are moving along similar physical pathways in these systems. Our study also indicates that geomorphic position is important for understanding soil and SOC movement and redistribution patterns within a field or watershed. Such information can help develop and implement management systems to increase SOC and reduce soil loss in agricultural ecosystems.