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The complex interactions between human activity and natural processes determine non-linear dynamics in ecosystems that can difficult their management. Human settlements in and lands contribute to the modification of disturbance regimes, including the introduction of new disturbances and the elimination of others. In consequence, they can alter the functional mechanisms that allow systems to overcome limiting factors, leading to desertification. in this revision, we evaluated the effects of the changes on disturbance regimes produced by the different forms of land transformation on the structure and function of ecosystems of the Monte Biogeographical Province, in Argentinean arid west. Two approaches were used: the analysis of land use history and the analysis of the effects of the main disturbances on the dynamics of different communities. We concluded that throughout the history of the Monte Desert, the joint action of natural and anthropic agents has resulted in complex dynamics that lead most area of the Monte to a moderate to severe status of desertification. The modification of the disturbance regime had strong consequences for several aspects of the dynamics of communities, such as species composition and diversity, water dynamics, soil conditions, trophic structure arid productivity of Monte Desert ecosystems. However, disturbance regimes could be managed to promote favorable transitions in ecosystems and, therefore, could be a tool for optimizing productivity of agro-ecosystems, and recovering and conserving natural ecosystems. (C) 2008 Elsevier Ltd. All rights reserved.