Modelling of sediment transport: Link in a chain

Rather than reporting on a specific topic of current research in the broad field of sediment transport and river morphology, the writer will give a general contemplation on the state of the art. This will not be a review in the usual sense. The alloted space would then be filled easily with references. References will only be made here if it cannot be avoided. Moreover only sediment transport due to currents will be treated. To avoid confusion it is necessary to indicate that modelling of sediment transport is used at present (1977) in at least three meanings: (i) A theoretical framework for sediment transport proper. This mainly implies a relation between hydraulic parameters and the amount of sediment transport. This framework will have to be supplemented with experimental data before a useful transport predictor is attained. (ii) A mathematical framework for morphological processes in rivers, used to forecast morphological changes in rivers e.g. due to human interference (morphological computations). (iii) A scale model with mobile bed of a river in order to carry out similar predictions as under (ii) (mobile-bed scale models). In which follows the vague term "modelling of sediment transport" will be avoided if confusion may be introduced