Abstract:Land degradation and desertification are major environmental problems of human societies in drylands of North and South America. Mexico is one of the most severely affected countries. An assessment of how both biophysical and socio-economic processes simultaneously affect, and are affected by, land degradation is recognized as one of the most important and challenging topics in the research on global change. Towards meeting this challenge, in June 2004 an interdisciplinary mix of scientists assembled in Mexico to participate in a workshop convened by the ARIDnet network. The focus of the workshop was to apply a new conceptual framework-the Dahlem Desertification Paradigm (DDP)-to La Amapola, a small rural community located in the Central Plateau of Mexico. The DDP aims to advance understanding of global desertification issues by focusing on the interrelationships within coupled human-environment systems that cause desertification. In this paper we summarize the conclusions of the La Amapola workshop. First, we present a brief review of some of the broader issues and concerns of global desertification, which led to the formation of ARIDnet and to the DDP. Second, we provide an overview of land degradation issues in La Amapola, highlighting examples of hydrological linkages between biophysical and socio-economic factors. Third, we summarize our findings in a conceptual model, which highlights linkages between biophysical and socio-economic factors in La Amapola, and the role of hydrology in desertification. Lastly, we discuss the results derived from the application of the major assertions of the DDP to La Amapola. The numerous feedbacks, linkages, and causal pathways between the biophysical and human dimensions suggest that hydrology is the fundamental component of the livelihoods of rural communities in this region of Mexico, and thus it is of central importance when evaluating desertification.