Seasonal Soil Loss and Erodibility Variation on a Miamian Silt Loam Soil
The importance of temporal soil erodibility variation is a subject of growing awareness but relatively little investigation. The aim of this study was to make a preliminary assessment of the trend and magnitude of seasonal variations in erosion and erodibility (factor K of the Universal Soil Loss Equation, USLE) for a soil in central Ohio. Three replicate runoff plots (22 by 4 m) were established at The Ohio State University Agronomy Farm, Columbus, and monitored for runoff and soil loss from autumn 1989 through summer 1991. Soil loss and erodibility varied significantly among seasons. Erodibility was high under wet, thawing soil conditions during the winter and spring due to low soil strength and greater susceptibility to detachment. Summer erodibilities were lowest in each year despite high soil loss from erosive rains. A measured 2-yr mean K factor of 0.039 t h MJ−1 mm−1 was in close agreement with the Wischmeier nomograph predicted value of 0.041 t h MJ−1 mm−1. Both, however, were lower than the published value (0.049 t h MJ−1 mm−1) for Miamian silt loam soil (fine, mixed, mesic Typic Hapludalf). Seasonal erodibility coefficient data exhibited a periodicity during the year, which could be approximated by a cosine-type function. Further, a lack of correlation between soil erodibility and seasonal rainfall erosivity was supported by the fact that highest per-event K did not correspond with storms of high erosivity factor R (EI30), erosivity and vice versa.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © .