Rapid land cover change in agricultural valleys of the Atacama Desert, Chile

Abstract

The profound landscape modification produced by agriculture is considered one of the main threats to biodiversity worldwide. Although the main ecological impacts are likely due to agricultural expansion into natural areas, changes in crop types and production intensification also induce significant ecological changes. We studied the land cover change process in four agricultural valleys (Lluta, Azapa, Vítor and Camarones) in the Atacama Desert of Chile between 2003 and 2019, divided into four equal periods. Using spatial data and logistic regression, we assessed the driving factors of land cover change. The Azapa valley showed the highest rate of land cover change, reaching 36.4% of netting and greenhouses landscape cover by the end of the study, and 50.4% annual rate of increase during the 2007–2011 period. Intensification was observed as the anti-aphid netting cover expanded mainly in Azapa and in the last four years in Vítor and Lluta valleys. Most land cover change was related to low slopes and elevation or sites closer to roads or surrounded by already cultivated land, like agriculture expansion on barren soil or native shrubland loss. High population density was significantly correlated with land cover change (p < 0.01). If land cover change into netting continues as observed, it is possible that landscape homogenization occurs in the short term in almost all valleys. Anyway, disentangling how landscape change works and the involved drivers, could be useful to understand landscape simplification in arid lands that are under an agricultural intensification process.