Modelling ephemeral gully erosion in small cultivated catchments

Degradation of soil physicochemical quality by ephemeral gully erosion on sloping cropland of the hilly Loess Plateau, China

“…This lack of information is partially because the development of EGE removes the evidence of their origin (Valentin et al, 2005) and, more importantly, because of the indirect and limited information on the effects of EGE on crop yield available to local farmers and policy-makers. As a result, most catchment-scale hydrology and soil erosion models lack adequate tools to address the initiation, development and subsequent effects of EGE on soil quality and productivity (Souchère et al, 2003;Poesen et al, 2003). The approach of this study in which field ground-truth survey of EGs is combined with laboratory analysis of samples in the gully and outside the gully demonstrated the significance of soil degradation caused by EGE.…”

Evaluating ephemeral gullies with a process-based topographic index model

“…An upstream drainage (or catchment) area per unit of contour length was calculated by dividing the drainage area by resolution of the DEM. The soil critical shear stress was calculated based on percentage of clay content (P c ) in topsoil (Smerdon and Beasley, 1961) Management practices and amount of land cover affect mechanical properties of topsoil, so τ cr must be adjusted accordingly Souchère et al, 2003;Gordon et al, 2007). In this study, wheat was planted one week prior to the formation of EGs, so the land could be considered bare and τ cr could be left unadjusted in Eq.…”

Gully Erosion in Europe

“…Kirkby et al (2003) presented power law equations describing the locations of ephemeral and permanent gully channel heads. Souchère et al (2003) combined an expert-based approach and field data to predict the location and volume of ephemeral gullies within the main runoff collector network of agricultural catchments in France. Casali et al (2003) and Torri and Borselli (2003) developed gully cross-section models to predict changes in gully channel width and depth during concentrated flow events in Spain and Italy.…”