Remote sensing for the study of climate change, intensive agriculture, and its effects on an overexploited fossil aquifer system, arid region, Atacama Desert

Pino-Vargas E.; Maquera-Callo E.; Choque-Machaca G.; Huayna G.; Chávarri-Velarde E.; Vera-Barrios B.; Ramos-Fernández L.; Ingolblanco E. · Proceedings of the IAHR World Congress (2025) · DOI: 10.64697/978-90-835589-7-4_41wc-p1951-cd

Resumen

The study region's olive trees and other economically significant crops have led to overexploitation of groundwater, which makes it necessary to ascertain their spatial and temporal evolution to manage irrigation from the Caplina aquifer's water. This system aquifer has been defined as a fossil aquifer, with the age of the water being dated between one thousand and fifteen thousand years old according to C14 results, which supports the idea that this aquifer has a very high recharge. Intensive agriculture and climate change have created uncertainty in water availability, resulting in issues with food security at the regional, national, and international levels. Using publicly accessible satellite imagery and machine learning methods, it was found that the agricultural area increased by 373.2% between 1985 and 2021, with the largest increase occurring between 2015 and 2021. In addition, VCI values increased steadily between 1985 and 2021 (from 0.1 to 0.98), indicating that there has been no drought since overuse of the aquifer system permits irrigation of the production regions. Furthermore, the TCI index has values that lack a clear trend across the study period, with drought occurring in 2000, 2005, and 2010 and not occurring in 1985, 1990, 1995, 2015, or 2021. According to the VHI index, there was a mild to moderate drought in 1990, 2000, 2005, and 2010; however, there was no drought in 1985, 1995, 2015, or 2021. Particularly in an overused aquifer with fossil characteristics that was developed between one thousand and fifteen thousand years ago and has very little or no recharge, these anomalies are linked to the observed climate fluctuation and change.

Instituciones: Universidad Nacional Agraria La Molina; Universidad Nacional de Moquegua; Universidad Nacional Jorge Basadre Grohmann