Introduction: (Zero net) land degradation - the main challenge

Desertification is one of the most important issues facing our societies because of its serious consequences for human health, landscape and the environment. Nonetheless, the issue has been in the eyes of media, decision makers and public opinion and it should be noted that this interest tends to be cyclical, corresponding to peaks that reflect the outbreak of emergency situations related to prolonged episodes of drought and water scarcity, in turn associated with climate changes. This volatile interest has focused on the relationship between desertification and climate change (and more generally on the biophysical factors underlying desertification), neglecting the important role played by social, economic, cultural, political and institutional factors. This role — brought to the fore by the most recent socioeconomic dynamics at various spatial scales — requires dedicated approaches from the scientific point of view and a less sensationalistic dissemination of research evidence. This book proposes a trans-disciplinary vision on issues of desertification and land degradation, focusing on long-term socio-ecological dynamics as an interpretative key to local systems’ complexity.