Population pressure and land degradation: The case of Ethiopia

This paper tests the population pressure hypothesis (PPH) for the Ethiopian Highlands using quantitative methods. The hypothesis posits that under comparable physical conditions heavily eroded areas occur in highly populated regions. A severity of soil erosion index (SESI), a proxy for some types of water erosion, was chosen as the dependent variable. Because the dependent variable is categorical and ordinal, an ordinal cumulative legit model was chosen for the analysis. The findings imply that as pressure from people and livestock exceeds some threshold, a rapid degradation of land take place. (C) 1996 Academic Press, Inc.