Land Degradation and Overgrazing in the Afar Region, Ethiopia: A Spatial Analysis

Pastoralist societies in dryland areas anticipate the harsh climatic conditions with migration patterns that optimise the use of available forage and watering points. Yet, these traditional institutions are under increasing pressure due to a mounting population, encroaching of traditional grazing areas by sedentary agriculture and restrictions on transboundary movements. Indeed, the last decades witnessed an intensified use of these rangelands and the threat of overgrazing, a major cause of land degradation, should be taken seriously. This also motivates the current study where we analyse the relationship between grazing patterns and land degradation in the nomadic pastoralist areas of the Afar Region, Ethiopia. However, this is not an easy task because trekking patterns and concentrated grazing areas are not known in sufficient detail to engage in a fully spatial temporal analysis. Therefore, we simulate the effect of migration by analysing land degradation-overgrazing relationships under various area accessibility scenarios, gradually releasing administrative boundary restrictions for pastoralists from district zone to state level. A grazing supply to demand ratio is applied to analyse the incidence of overgrazing whereas land degradation is estimated using time series analysis of the Rainfall Use Efficiency (RUE). The study shows that fodder shortages at district level in the western Afar are partly compensated at zonal level while the demand-supply ratio at state level is close to one. Significant negative trends in RUE are found in the north-eastern part of the Afar, in isolated pockets along the Awash River and near escarpments with the Highlands. A better understanding of the land degradation-overgrazing relationship requires more information on trekking patterns, including possible visits outside the study area.