Implications of scale, slope, tillage operation and direction in the estimation of surface depression storage

Many studies on soil microrelief, or roughness, have identified a multi-scale behaviour of roughness. However most of the literature on the surface storage of precipitation is based on experiments conducted over very small sampling areas, usually not large enough to reflect the large scale components of roughness. In this paper a 5 m long surface roughness profile database is studied with the main objective of assessing the scaling behaviour of surface storage and the role that surface slope and tillage direction play on this phenomenon. In particular, in was evaluated whether the measurement domain size (profile length) and resolution (sampling interval) had any influence on the calculated storage values. Results illustrate a multiscale behaviour of surface storage, with larger storage values obtained for longer profiles and smaller sampling intervals. Tillage operations significantly affect observed storage values and their variability. Tillage direction also had a significant role in the calculated storage values, however its importance decreased clearly over areas of increasing slopes. (C) 2010 Elsevier B.V. All rights reserved.