In the studyed scenario the change of cattle raising and tarditional agriculture has substantally impacted the fundiary structure and also the karst.

This study was developed using digital Landsat-TM image (WRS 218/74-B) collected in july 1997. TM bands 3,4 and 5 were chosen as imput to digital analysis with the support of SITIM/INPE software. These Landsat data were submited to a linear contrast strech enhansement and HSI (Hue, saturation and intensity) transform to provide the best visual separation of the karstic relief units. The visual analysis of the spectral and spatial characteristics of the data, indicated that the results obtained with that approach were similar with the field data.The digital Landsat-TM image shows the differents karst units and their different land use:

I. COVERED KARST : <780m - Cretaceous Planation Surface, sandy soils, lateritic duricrust, savana, extensive cattle farms. 750 - 780m - South American Surface (Oligocene - Miocene), lateritic soils, duricrust, savana, pasture, semi intensive cattle farms.
II. KARST: 615-750m - Fluviokarst,doline landscape, karren field, restricted land use. 500-700m - Escalonated escarpment, karren field, no land use.
III. SÃO FRANCISCO KARST PLAIN: 440 - 500m - Dissolution dolines, irrigation systems (channels-river warer; aerial-groundwater), agroindustrial settlements and semi intensive cattle farms.
IV: SÃ O FRANCISCO FLOOD PLAIN: 440 - 444m - Marginal dique, sand banks, marginal lakes, no land use.

*This research was supported by FAPEMIG (Fundaçao de Amparo á Pesquisa do Estado de Minas Gerais).