Status of desertification in the Patagonian region: Assessment and mapping from satellite imagery

Desertification advance in the Patagonian region is the main socioecological problem. However, in this region the precise location, extent, severity, and characteristics of desertification are often unknown. The objectives of this research were (1) to evaluate, classify, and interpret the status of desertification, based on biological and physical indicators in the Patagonian arid, semiarid, and subhumid region of Argentina; (2) to develop a map of desertification with recommendations for decision makers; and (3) to create a methodology to determine accurately the distribution of land degradation from satellite imagery. Data were obtained from selected cloud‐free scenes of the National Oceanographic and Atmospheric Administration/Advanced Very High Resolution Radiometer “large‐area coverage” (NOAA/AVHRR LAC), existing data, and intensive field observations. The combination of the coarse‐resolution satellite data of this study with fine‐resolution satellite data Landsat multispectral scanner (MSS) were the basis for the region‐wide assessment of desertification status. From the total region studied (78.5 million ha), 93.6% (73.5 million ha) showed different degrees of desertification. Categories of desertification for the whole region were slight (9.3%), moderate (17.1%), moderate to severe (35.4%), severe (23.3%), and very severe (8.5%). The provinces where reclamation and/or control measures should be applied are, in order of priority, Santa Cruz, Neuquén, Chubut, Río Negro, and Tierra del Fuego archipelago. Considering the lack of a common management strategy among the provinces, it is recommended (1) to give importance to landscape diversity when managing natural resources, (2) to suggest alternative livestock grazing schemes and management of the environmental heterogeneity, (3) to revegetate or restore degraded areas, (4) to declare some areas Provincial Reserves, and (5) to exclude livestock and collection of firewood either temporarily or permanently.