| Abstract: | The mechanics of soil erosion from irrigated and rainfed lands are similar. Soil particles are detached,transported and deposited. However, there are some systematic differences between irrigation and rainfallerosion. Electrolyte concentrations in irrigation water, for example, are almost always greater than in rainwater. Differences between rainfall and irrigation are more prominent for surface irrigation than forsprinkler irrigation. For instance, rainfall wets the soil before runoff begins, but water initially flows ontodry soil in irrigation furrows. Furthermore, furrow flow rate decreases with distance and increases withtime, while the opposite tends to occur with rainfall. For sprinkler systems, travel direction and slopeaspect interact, so runoff can flow within the irrigated area or from the irrigated area onto dry or wet soil.Thus, a sprinkler-irrigation erosion model must consider both the rainfall-runoff situation and the furrowflow situation. These differences in soil and water interactions must be considered before computermodels can accurately simulate irrigation-induced soil erosion. |
