Modification du régime des précipitations et risque de stress hydrique des formations végétales en zone de forêt dense humide ivoirienne

Abstract

South part of Ivory Coast is a tropical forest zone. This forest is in two parts : wet tropical forest in the south of the zone and dry forest in the north of this zone. The repartition of these two kinds of forest is linked to tropical climate. Thereby, all changes in available water ressources can modify forest ecosystem. This problem and especially the decrease, and sometimes the lack, of precipitation has begun for about twenty five years. This involves disturbances and even recession of forested areas. The aim of this study is to evaluate impacts of actual climatical changes on forested areas. To achieve it, we both use NOAA-AVHRR data transform into Normalized Difference Vegetation Index and rain water budget to shows how rainfall decrease can alterate forest ecosystem. We also deal with impact of anthropic factor on forest ecosystem evolution such as crops extension.