Zoneamento em unidades morfológicas da bacia do rio Oudon, Noroeste da França, a partir de MDT em ambiente SIG

Résumé En

This paper analyzes relief attributes defining units with homogeneouscharacteristics, for river Oudon basin, located northwest of France, in the department ofMayenne and Maine-et-Loire, delimited by the geographic coordinates 47∞33í31.54" ‡48∞ 4í41.51"de latitude N e 0∞41' 35.69" ‡ 1∞20' 8.54" de longitude W. How base mapused a Digital Terrain Model in the northwest of France of the Institut NationalGÈographique, with a spatial resolution of 50m. Through spatial area the raster of thehigh there was obtained the characteristics elevation, maximum, minimum, averageheight and amplitude. By the tool of ArcGIS were certain about drainage, slope andgeomorphometric units, separate down by a decision tree. The morphological classificationand mapping to identify the units with similar characteristics as the features relief. Thisprocess involved the interpretation and visual analysis, using the superposition of layersin GIS. This analysis allowed us to define seven homogenous relief units in the Oudonbasin: Unit of the Plane Areas of high course, Unity of the Valley of Dissection, Unit ofthe gently hills of the upper course, Unit hills with elevations isolated, Unit Plateausscalloped, Unit Valleys between Plateaus, Unit flat areas along the mouth. Themorphological classification and mapping has shown potential to be used in survey workand planning considering that the forms of relief exercising decisive role in the exposuretime of materials, the intensity and direction of water flow.