RT Journal Article
T1 Unraveling groundwater functioning and nitrate attenuation in evaporitic karst systems from southern Spain: an isotopic approach.
A1 Valiente, Nicolás
A1 Gil-Márquez, José Manuel
A1 Gómez-Alday, Juan José
A1 Andreo-Navarro, Bartolomé
K1 Aguas subterráneas
K1 Isótopos estables
K1 Sal
K1 Hidrología kárstica
K1 Nitratos
AB High evaporation rates in semi-arid to arid regions result in an increase in salinity that can exacerbate the effect of pollutants in water bodies.This study examines how groundwater drives pollution removal in wetlands, wells and springs within the Chaotic Subbetic Complexes (southern Spain). This evaporitic system, localy with a clear karstic functioning, is characterized by groundwater with a wide range of mineralization. Hydrochemical and multi-isotopic (δ34S, δ18O, δ15N, δ13C and δ2H) techniques were used to understand the geochemical processes leading to pollutant attenuation within the complexes. There, regional groundwater evolve from recharge/transition areas, with low salinity, to the discharge zone. Mineralization of groundwater depends on the dissolution of evaporitic deposits (gypsum, halite) of Keuper age, which increases salinity of the water drained by the outlet springs. δ15N and δ18O values of dissolved nitrate (NO3−) were used to estimate the relative contribution of N sources. NO3− is mainly derived from agricultural inputs (nitrate and urea fertilizers). Long-residence groundwater plays an important role in the biogeochemical evolution. Denitrification is responsible for NO3− removal in transitional zones and discharge springs. This process is promoted by the oxidation of organic carbon, derived from recharge areas and further transported to deeper zones of the aquifer. The findings of this study provide a new understanding of how hydrogeological functioning is connected to pollutant removal in an evaporitic karst system, where the scale of groundwater flows plays a key role in biogeochemical processes.
PB Elsevier
YR 2020
FD 2020-11-05
LK https://hdl.handle.net/10630/36509
UL https://hdl.handle.net/10630/36509
LA spa
NO Nicolas Valiente, José Manuel Gil-Márquez, Juan José Gómez-Alday, Bartolomé Andreo, Unraveling groundwater functioning and nitrate attenuation in evaporitic karst systems from southern Spain: An isotopic approach, Applied Geochemistry, Volume 123, 2020, 104820, ISSN 0883-2927, https://doi.org/10.1016/j.apgeochem.2020.104820.
NO Proyectos de excelencia  de la Junta de Andalucía P11-RNM-8087 y P10-RNM-6895R, proyecto SBPLY/17/180501/000296 de Castilla-La Mancha y proyecto CICYT-CGL2017-87216-C4-2-R del Ministerio de Investigación. Grupo RNM-308 de la Junta de Andalucía.
DS RIUMA. Repositorio Institucional de la Universidad de Málaga
RD 20 ene 2026