Formalisation of soil-landscape knowledge through interactive hierarchical disaggregation

The soil-landscape model strongly depends on scarcely documented expert knowledge. In this paper a methodological framework is formulated that takes advantage of a GIS to interactively formalise soil-landscape knowledge using stepwise image interpretation and inductive learning of soil-landscape relationships. It examines topology to keep record of potential part of relationships between terrain objects denoting discontinuities in soil formation regimes. The relationships are used to visualise the pathway along which terrain objects have been derived. They can be applied in similar areas to facilitate image interpretation by restricting possible lower-level terrain objects. The framework may adopt different inductive methods to describe soil variation in relation to a terrain description. It is illustrated using stratification of soil texture data according to terrain object classes in a case study within the Guadalhorce basin in southern Spain. The degree of association between terrain object classes and particle size classes increased from 6% to 38% in three steps of image interpretation.