Integration of GIS and a dynamic spatially distributed model for non-point source pollution management

The integrated system described in the paper combines GIS software based on a vector data structure with a simulation model for non-point source pollution management Territory is disaggregated to spatial modelling units through a series of map overlays. The two major software components are linked through a set of the GIS package's macro language routines and operating system script files. The level of integration can be described as ''running the model as a GIS subsystem.'' It contains the following steps: invoking the GIS software; calling the model for a simulation run (with possible input editing); import of the model output to a GIS compatible database file; establishing a file relation between the model output and the georeferenced attribute file; and displaying and analysing model results. The user interface is menu driven, and options are provided for defining the temporal and spatial extent of the modelling session. After a simulation run, results are available for further analysis in the form of a classification map and a network loaded with the simulated variable. Copyright (C) 1996 IAWQ.