title: Present and future of desertification in Spain: Implementation of a surveillance system to prevent land degradation.
abstract: Mitigation strategies are crucial for desertification given that once degradation starts, other solutions are extremely expensive or unworkable. Prevention is key to handle this problem and solutions should be based on spotting and deactivating the stressors of the system. Following this topic, the Spanish Plan of Action to Combat Desertification (SPACD) created the basis for implementing two innovative approaches to evaluate the threat of land degradation in the country. This paper presents tools for preventing desertification in the form of a geomatic approach to enable the periodic assessments of the status and trends of land condition. Also System Dynamics modelling has been used to integrate bio-physical and socio-economic aspects of desertification to explain and analyse degradation in the main hot spots detected in Spain. The 2dRUE procedure was implemented to map the land-condition status by comparing potential land productivity according to water availability, the limiting factor in arid lands, with plant-biomass data. This assessment showed that 20% of the territory is degraded and an additional 1% is actively degrading. System Dynamics modelling was applied to study the five desertification landscapes identified by the SPACD. The risk analysis, implemented on these models, concluded that 'Herbaceous crops affected by soil erosion' is the landscape most at risk, while the Plackett-Burman sensitivity analysis used to rank the factors highlighted the supremacy of climatic factors above socioeconomic drivers.
authors.affiliation: Estación Experimental de Zonas Áridas, Consejo Superior de Investigaciones Científicas, 04120 Almería, Spain. Electronic address: jaimonides@eeza.csic.es.
authors.forename: Jaime
authors.initials: J
authors.lastname: Martínez-Valderrama
authors.affiliation: Departamento de Economía Agraria, Estadística y Gestión de Empresas, Universidad Politécnica de Madrid, 28040 Madrid, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Ibáñez
authors.affiliation: Estación Experimental de Zonas Áridas, Consejo Superior de Investigaciones Científicas, 04120 Almería, Spain.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Del Barrio
authors.affiliation: Estación Experimental de Zonas Áridas, Consejo Superior de Investigaciones Científicas, 04120 Almería, Spain.
authors.forename: Maria E
authors.initials: ME
authors.lastname: Sanjuán
authors.affiliation: Civil Engineering Research and Innovation for Sustainability (CERis), Instituto Superior Técnico, University of Lisbon, 1049-001 Lisbon, Portugal; Instituto de Ciencias Químicas Aplicadas, Facultad de Ingeniería, Universidad Autónoma de Chile, 7500138 Santiago, Chile; Faculty of Agricultural Sciences, Technical University of Ambato, 180104 Ambato, Ecuador.
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Alcalá
authors.affiliation: Centro de Ciencias Humanas y Sociales, Consejo Superior de Investigaciones Científicas, 28037 Madrid, Spain.
authors.forename: Silvio
authors.initials: S
authors.lastname: Martínez-Vicente
authors.affiliation: Estación Experimental de Zonas Áridas, Consejo Superior de Investigaciones Científicas, 04120 Almería, Spain.
authors.forename: Alberto
authors.initials: A
authors.lastname: Ruiz
authors.affiliation: Estación Experimental de Zonas Áridas, Consejo Superior de Investigaciones Científicas, 04120 Almería, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Puigdefábregas
keywords: 2dRUE procedure; Desertification; Early warning system; Risk analysis; System Dynamics modelling