Assessing flooding patterns in llanos of the Apure region (Venezuela) using radar images
Keywords:
Apure, savanna, river floodplain, radar images, flooding regime, seasonal impacts, hyperseasonal savannaAbstract
In the flooding savannas of the Llanos del Orinoco water is the main factor determining the ecosystem and its changes. During
flooding, the water level and flood duration depend highly on the relative height position of the ecosystem unit. To understand
the spatial processes in the ecosystem it is important to know the water dynamics. The Llanos is an alluvial basin with sediments
from the lower-middle Pleistocene until the present. Terrain differences within de Llanos between the Arauca and the Apure
River are small. A flood map has been constructed for the regional level and for the area of the hacienda Hato el Frio. For the
analysis of the flooding pattern use has been made of radar images. Field data have been collected in the area of hacienda Hato
el Frio to be used for interpreting the radar images. In the flood map, an increase of inundation from the dry to the wet season
can be observed. At the end of the dry season few areas are covered with water; in the wet season approximately half of the
area is inundated. Gallery forests were extracted from a classified Landsat image. The methods applied appear to be valid to the
classification and monitoring of inundation, but only the spatial extent is obtained with this method as the radar images do not
measure water depths.
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Copyright (c) 2018 R.H.G. Jongman, J.K. Smith, E.J. Chacón-Moreno, J.H. Loedeman (Autor/a)
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