Dynamics Analysis and Factors in Landscape Units’ Evolution in Senegal River Delta Ecosystems

Abstract

Nowadays, the dynamics of the Senegal river delta ecosystem has attracted the attention of the authorities because of the profound changes which it is subject. This study aims to analyze the relationship between the dynamics of land use units and natural and anthropogenic factors. It is performed by means of remote sensing and GIS data. Landsat images, acquired in 1977, 1988, 1999, 2006 and 2014 are chosen for this purpose. Supervised classification by maximum likelihood on neo-channel (ACP and NDVI), has allowed making the evolution of landscape units cards. These results are coupled with field data and statistics obtained in the state structures. The analysis showed that the natural and human factors are causing mutations noted in the Senegal delta ecosystems. Supervised classification has to show an expansion rate of vegetation cover (64%) crop areas (6.77%), surface water (4%) and regression of salted areas (74.69%) and dune (15.62%) between 1977 and 2014. The significant increases are due mainly to irrigation schemes, population growth and protection policies and conservation of natural resources while regressions observed, are related to the development of the agricultural sector in recent years and the importance of rainfall limiting biophysical processes. The results of this study can serve as capacity strengthening tools for actors in the field, to the understanding of the mechanisms and processes of degradation of delta ecosystems to consider adaptation measures on the rational management of space natural.