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The study area is located in the NE part of Peloponnese (Corinthos prefecture, South Greece). It is one of the most intense agricultural areas of Greece cultivated mainly with vines, citrus and olive trees. The land cover/use changes, observed during last years, are significant, given that the area composes an important road junction in south Greece and the pressure to the natural environment is getting higher and higher.

The human pressure is related with the rapid expansion of the urban areas, fires, overgrazing in semi-mountainous or mountainous areas, vegetation downgrading, the penetration of cultivations into natural vegetation zones and the intense erosion phenomena. All these consequences lead, mainly, to the deforestation, with a relatively slow but stable rate, and the appearance of some desertification indications (permanent bare lands, bare rocks, intense erosion).

Remote sensing potentially offers a relatively low-cost approach for examining the human and natural induced changes in land cover/use that may have an impact on agricultural and physical environment leading to all above-mentioned problems. A three-band SPOT-2 XS scene (1998) and SPOT-1 XS scene (1986) were used. The two multispectral images were properly processed and classified separately with maximum likelihood classifier, using additionally a Digital Elevation Model for better results, to extract thematic information concerning land cover/use. Two thematic maps with high accuracy were produced and overlaid with the Cross operation, comparing pixels at the same positions.

The application presented here was focused on the analysis of the information extracted from two SPOT images regarding the land cover/use change detection during the span of 12 years (1986-1998). This study demonstrates the usefulness of remote sensing techniques and satellite data in order to detect and map all the deforested areas and the probable desertified prone areas, in a part of Corinthos prefecture.

Finally, the input of remote sensing data in a GIS makes easier their processing and their correlation with other conventional data, such as Digital Elevation Model (DEM), thematic maps and field work, for more accurate identification, assessment and mapping of land cover/use changes, with emphasis in deforestation and desertification phenomenon. The repeated monitoring and mapping of land cover/use changes is imperative in order to contribute to the suitable management of land cover/use, the conservation of natural environment and the sustainable management of the natural resources.