ABSTRACT
Water erosion on slopes is due to three distinct processes. Before runoff is generated, erosion occurs by splash due to the action of raindrops only. After runoff generation, the irregular and unconcentrated flow on hillslopes can transport sediments. Such a mechanism is termed interrill erosion. As flow accumulates, there is a tendency for it to concentrate in more hydraulically efficient areas. These are termed rills or gullies, depending on their size. A fourth erosion process is common in certain areas under the surface, leading to the formation of soil pipes.
