Contribution of NDVI-AVHRR images in the characterization of the hydrological response of the Agneby and Boubo watersheds (Côte d'Ivoire)

Résumé

The characterization of the hydrological response of watersheds and Agneby Boubo is performed to simultaneously monitor changes in land use and impacts on runoff. Data from the study are satellite images (NDVI-AVHRR) and hydro rainfall statements (outflow and rain). The tools used are mainly composed of Windisp 5.1 software, for the treatment of NDVI images, MapInfo Professional 6.5 and ArcView 3.2a for scanning cards.

The methodology focused on the spatio-temporal analysis of the photosynthetic activity of the study area, on the one hand and the highlight of the hydrological behavior of the basin based on a linear model, on the other.

The results show a continued degradation of plant cover, despite a slight recovery of plant activity between 1985 and 1990. Rainfall is the investigator for the resumption of plant activity, after the dry season, it actually takes one to two decades when the first rains appear. In terms of flows, changes in land use have disrupted the flow regime. More degradation is pronounced, more flows are important.