Physically-Based River Basin Modelling within a GIS: the LISFLOOD Model.

Although many geographical information systems (GISs) are very advanced in data processing and display, current GIS are not capable of physically based modelling. Especially, simulating transport of water and pollutants through landscapes is a problem in a GIS environment. A number of specific routing methods are needed in a GIS for hydrologic modelling, amongst these are the numerical solutions of the Saint-Venant equations, such as the kinematic wave approximation for transport of surface water in a landscape. The PCRaster Spatial Modelling language is a GIS capable of dynamic modelling. It has been extended recently with a kinematic wave approximation simulation tool to allow for physically based water flow modelling. The LISFLOOD model is an example of a physically based model written using the PCRaster GIS environment. The LISFLOOD model simulates river discharge in a drainage basin as a function of spatial data on topography, soils and land cover. Although hydrological modelling capabilities have largely increased, there is still a need for development of other routing methods, such as a diffusion wave. Copyright © 2000 John Wiley & Sons, Ltd.