Infiltratie en herverdeling van water in grond

The flow of the liquid phase trough a soil can be predicted from pressure gradients. Different ways of predicting infiltration for irrigation of a basin were compared: numerical approximation; semianalytical; and analytical. A partly emperical equation was developed for description of rate of infiltration, after examination of existing equations. Under certain condions, infiltration was influenced by under or over pressure of the trapped gas phase and by swelling of clays. Complex models for redistribution were of little value in practice, since they could not be generalized and required too much physical data about the soil. A scheme was developed that grouped techniques for estimating physical properties of soil, according to cost and expertise required.