Land management and soil degradation evidence during the Late Holocene in Northwest Argentina (La Costa 2-Tafi valley)

The Tafi valley (Northwest Argentina) was densely occupied by agropastoral societies during the Late Holocene. These peoples made profound changes in the landscape during the development of productive economies. Previous geomorphological and geoarchaeological studies have produced good basic information about the Holocene landscape evolution of this semiarid region. However, little is known about the relationship between human activities and landscape responses. The alluvial fans forming the valley's piedmonts show morphosedimentary records that could be related to environmental changes and, from Late Holocene, with human activities. Agropastoral settlements started in the Formative Period (ca. 2500 yr BP) and land exploitation practices produced a profound degradative impact. This paper applies geoarchaeological techniques to explore the magnitude of the geomorphological and edaphic alterations introduced by man. Analyzed records enabled us to make an evaluation of erosive and degradative processes produced as dynamic geomorphological responses to human interventions. These processes were decisive for the current configuration of the valley.