Mapping of land-cover from remotely sensed images in the valley of Oued Righ (Algerian southeast)

Abstract

The aim of this work is to analyze the evolution of arid areas by remote sensing and to assess the extent of landscape changes over time. The study consists of a multitemporal analysis of LANDSAT TM and ETM + satellite images from 1987, 2000 and 2009 covering the Oued Righ valley in south-eastern Algeria.

Numerous colored compositions carried out, allowed us a very good visual characterization of the surface states. Supervised classification charts, carried at the second step, are of good quality as indicated by the precision indices and Kappa indices from the various confusion matrices.

The change maps obtained by diachronic analysis of the classifications carried out show a clear modification of the natural landscape with a significant increase in the surface of the water, the number of the population and a reduction of the palm groves.

Keywords: Remote sensing; Change mapping; land cover; multitemporal analysis; Northern Sahara