Soils under no-tillage (NT) and a moldboard plow tillage system (MT) were exposed to a field rainfall simulation to determine the soil poorly crystalline iron release during interrill erosion. Clay/silt-sized particles were captured in an overland flow produced by a rainfall simulation in the field. Two different soils (Calloway silt and Maury silt loam) were exposed to different kinetic energy wettings to evaluate the temporal clay/silt sized release, the variation of the enrichment ratio for poorly crystalline iron (ERFe) and the total poorly crystalline iron delivered (TID). The clay/silt sized particles release was continuous and independent of soil texture. In both soils the ERFe decreased over the time, but showing unexpected flushes. These extreme values appeared at different time, thus indicating that they were conditioned for the aggregate's rupture. However, no correlation was found with the flushes of clay/silt sized particles. The ERFe data suggested the presence of Fe(ox) easy-to-release in the soil surface, which does not depend on the wetting energy used for the aggregate breakdown. The variations in ERFe were due to a soil characteristic affected for submergence. Under intensive tillage (MT) in both soils, the high kinetic energy wetting determined the highest TID. A low TID value was observed with low kinetic energy wetting, which provide evidence of a continuous mobilization of poorly crystallized iron from these soils. This occurred because a flow transports process and a labile source of Fe(ox). Because the cover surface was not sufficient to stop the clay/silt sized particles and the iron(ox) mobilization it would be preferable to combine NT with contouring as a better solution.
|Number of pages
|Published - Jan 1 2015
Bibliographical noteFunding Information:
The research that prompted this manuscript was funded by the Department of Plant and Soil Science, College of Agriculture, University of Kentucky, USA. We thank Dr. Workman, Lloyd Dunn and Martin Vandiviere for conceal and assistance. We also desire to express our recognition to the anonymous reviewers, because their suggestions and comments greatly contribute to enhance our manuscript.
- Clay-sized particle release
- Enrichment ratio in poorly crystalline iron (ER)
- Interrill erosion
- Total poorly crystalline iron delivered (TID)
- Wetting energy
ASJC Scopus subject areas
- Earth-Surface Processes