Skip to Main content Skip to Navigation
Journal articles

A Forty-Year Karstic Critical Zone Survey (Baget Catchment, Pyrenees-France): Lithologic and Hydroclimatic Controls on Seasonal and Inter-Annual Variations of Stream Water Chemical Composition, pCO2, and Carbonate Equilibrium

Abstract : The long-term trends and seasonal patterns of stream water chemical composition in a small remote forested karst catchment, were investigated from 1978 to 2018. Calcium, magnesium, and bicarbonates, the dominant ions, increased over the period together with temperature, while sulfates decreased. Carbonate and sulfate mineral dissolution was the main source of these elements. These trends and the seasonal opposite patterns of discharge vs. temperature, calcite saturation index vs. pCO2 and bicarbonate vs. sulfates, suggested the influence of discharge, of reduced long-range atmospheric pollution, and of increasing air temperature on biological activity and carbonate dissolution. Furthermore, the hydrological regime controlled the seasonal stream water chemical composition and fluxes by: (i) a dilution during the high discharge period, (ii) a change in the contribution rate of the waters draining different lithological areas in the catchment, e.g., the increased sulfates to bicarbonates ratio during summer low flows, with a maximum alkalinity decrease of 24%, and (iii) a "piston" and a "flushing" effects of dissolved elements stored in soils and epikarst with the first autumn heavy rains. Long-term stream water hydrochemical surveys of karst system have proved to be powerful indicators of biogeochemical processes, water sources and pathways under variable natural and anthropogenic environmental pressure conditions.
Complete list of metadata

Cited literature [151 references]  Display  Hide  Download

https://hal.archives-ouvertes.fr/hal-02999630
Contributor : Anne Probst Connect in order to contact the contributor
Submitted on : Tuesday, November 10, 2020 - 10:49:50 PM
Last modification on : Tuesday, October 19, 2021 - 11:10:03 PM
Long-term archiving on: : Friday, February 12, 2021 - 12:28:45 PM

File

Ulloa et al_Water_2020.pdf
Publication funded by an institution

Licence


Distributed under a Creative Commons Attribution 4.0 International License

Identifiers

Citation

Francesco Ulloa-Cedamanos, Jean-Luc Probst, Stéphane Binet, Thierry Camboulive, Virginie Payre-Suc, et al.. A Forty-Year Karstic Critical Zone Survey (Baget Catchment, Pyrenees-France): Lithologic and Hydroclimatic Controls on Seasonal and Inter-Annual Variations of Stream Water Chemical Composition, pCO2, and Carbonate Equilibrium. Water, MDPI, 2020, 12 (5), pp.1227. ⟨10.3390/w12051227⟩. ⟨hal-02999630⟩

Share

Metrics

Record views

196

Files downloads

275