Key hydrological processes in the Del Azul Creek basin, sub-humid Pampean Plain.

Autor: Zabala ME; Instituto de Hidrología de Llanuras 'Dr. Eduardo J. Usunoff' (IHLLA), República de Italia 780, Azul, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. Rivadavia 1917, Ciudad Autónoma de Buenos Aires, Argentina; Universidad Nacional del Centro de la Provincia de Buenos Aires, Pinto 399, Tandil, Buenos Aires, Argentina. Electronic address: mzabala@ihlla.org.ar., Gorocito M; Instituto de Hidrología de Llanuras 'Dr. Eduardo J. Usunoff' (IHLLA), República de Italia 780, Azul, Buenos Aires, Argentina; Agencia Nacional de Promoción Científica y Tecnológica, Godoy Cruz 2370, Ciudad Autónoma de Buenos Aires, Argentina., Dietrich S; Instituto de Hidrología de Llanuras 'Dr. Eduardo J. Usunoff' (IHLLA), República de Italia 780, Azul, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. Rivadavia 1917, Ciudad Autónoma de Buenos Aires, Argentina; Universidad Nacional del Centro de la Provincia de Buenos Aires, Pinto 399, Tandil, Buenos Aires, Argentina., Varni M; Instituto de Hidrología de Llanuras 'Dr. Eduardo J. Usunoff' (IHLLA), República de Italia 780, Azul, Buenos Aires, Argentina; Universidad Nacional del Centro de la Provincia de Buenos Aires, Pinto 399, Tandil, Buenos Aires, Argentina., Murillo RS; Stable Isotopes Research Group and Water Resources Management Laboratory, Universidad Nacional, Heredia 86-3000, Costa Rica., Manzano M; Escuela de Ingeniería de Caminos, Canales y Puertos y de Ingeniería de Minas, Universidad Politécnica de Cartagena, P° de Alfonso XIII 52, E-30203 Cartagena, Spain., Ceballos E; Instituto de Hidrología de Llanuras 'Dr. Eduardo J. Usunoff' (IHLLA), República de Italia 780, Azul, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. Rivadavia 1917, Ciudad Autónoma de Buenos Aires, Argentina.
Jazyk: angličtina
Zdroj: The Science of the total environment [Sci Total Environ] 2021 Feb 01; Vol. 754, pp. 142258. Date of Electronic Publication: 2020 Sep 12.
DOI: 10.1016/j.scitotenv.2020.142258
Abstrakt: Groundwater plays an important role in the economic development of the Chaco-Pampean Plain (Argentina), where industry, agriculture and cattle farming are the main economic activities. The 66% of the country's population lives in this area. The low slopes of this region condition the water movement and the occurrence of physical and chemical processes. The aim of this work is to update the hydrological conceptual model of the Del Azul Creek basin (Buenos Aires Province), a sub-humid and continental plain, using environmental tracers. In total, the study was based on the analysis of 201 samples (stable isotopes) and 184 samples (chemical data) including rainwater, surface water and groundwater. The temporal and spatial variation in the isotopic composition of rainfall and the hydrological physical-processes, evaporation, surface water-groundwater interaction and recharge were studied. Isotopic compositions of rainfall revealed a seasonal variation across the basin. Low δ 18 O rainfalls occur during the coldest seasons, while high δ 18 O rainfalls occur during the warmest seasons. The isotopic compositions of rainfall varied only during the cold period in the upper basin. At this time, the lowest δ 18 O rainfall fell in the upper basin, while in the other areas and during the warmer seasons, no differences were observed. Evaporation was a relevant process in the flatter area of the basin, mainly during the warmest seasons. Samples taken from the wetlands and from the lower section of the Del Azul Creek were strongly evaporated. In the first 30 m depth of the aquifer, groundwater reflected the isotopic composition of rainfall from the warmest seasons, thus revealing seasonal preferential recharge and a good hydraulic connection. This study provides direct evidence showing that both evaporation and the surface water-groundwater interaction are processes that play a key role in the control of the isotopic and chemical composition of water.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2020 Elsevier B.V. All rights reserved.)
Databáze: MEDLINE
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