In this type of approach, an important problem is the choice of the expert knowledge representation. In effect, it must be adequate for the deductive process using data extracted from the G.I.S. or computed on the remotely sensed images.

Two approaches were tested: expert systems and fuzzy neural networks.

In order to introduce the present system, we first describe an expert system approach using production rules and certainty factors.

Then we present the fuzzy neural networks system conceived for G.I.S. based problem- solving.