Facies identification within the playa-lakes of the Monegros desert, Spain, from field and satellite data

The Monegros desert and its saline wetlands, called saladas (literally translated as “the salties”), are a unique European landscape of great scientific and ecological value. The saladas (i.e., playa-lakes and other small saline depressions) are dynamic environments; changing their surface morphology on a seasonal–diurnal basis in response to both climate and groundwater fluxes. To depict changes in these natural systems, we have identified five surface facies classes which are detectable both in the field and from remote sensing data. These facies are crucial for describing and promoting the protection of these habitats. Remote sensing has provided worthwhile historical data and additional information that compensate for scarce field records. Combined field and satellite criteria are used to catalog these facies with a new conceptual integration that manages the asynchronism between the field and satellite data. The catalog of facies is intended to be helpful for monitoring these wetlands, and for understanding the current hydrological patterns and trends in the playa-lakes. This work will serve as a baseline for studying the future evolution of the saladas which may soon fall under manmade environmental forces such as increased water input from adjacent newly irrigated lands. It is hoped that identification of these facies will be useful, with minor adaptations, in using more advanced sensors or in studying similar habitats.