Zoneamento em unidades morfológicas da bacia do rio Oudon, Noroeste da França, a partir de MDT em ambiente SIG
Résumé
This paper analyzes relief attributes defining units with homogeneous
characteristics, for river Oudon basin, located northwest of France, in the department of
Mayenne 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 map
used a Digital Terrain Model in the northwest of France of the Institut National
GÈographique, with a spatial resolution of 50m. Through spatial area the raster of the
high there was obtained the characteristics elevation, maximum, minimum, average
height and amplitude. By the tool of ArcGIS were certain about drainage, slope and
geomorphometric units, separate down by a decision tree. The morphological classification
and mapping to identify the units with similar characteristics as the features relief. This
process involved the interpretation and visual analysis, using the superposition of layers
in GIS. This analysis allowed us to define seven homogenous relief units in the Oudon
basin: Unit of the Plane Areas of high course, Unity of the Valley of Dissection, Unit of
the gently hills of the upper course, Unit hills with elevations isolated, Unit Plateaus
scalloped, Unit Valleys between Plateaus, Unit flat areas along the mouth. The
morphological classification and mapping has shown potential to be used in survey work
and planning considering that the forms of relief exercising decisive role in the exposure
time of materials, the intensity and direction of water flow.