Title data
Gilfedder, Benjamin Silas ; Frei, Sven ; Hofmann, Harald ; Cartwright, Ian:
Groundwater discharge to wetlands driven by storm and flood events: Quantification using continuous Radon-222 and electrical conductivity measurements and dynamic mass-balance modelling.
In: Geochimica et Cosmochimica Acta.
Vol. 165
(2015)
.
- pp. 161-177.
ISSN 0016-7037
DOI: https://doi.org/10.1016/j.gca.2015.05.037
Abstract in another language
The dynamic response of groundwater discharge to external influences such as rainfall is an often neglected part of water and solute balances in wetlands. Here we develop a new field platform for long-term continuous 222Rn and electrical conductivity (EC) measurements at Sale Wetland, Australia to study the response of groundwater discharge to storm and flood events. The field measurements, combined with dynamic mass-balance modelling, demonstrate that the groundwater flux can increase from 3 to ∼20 mm d-1 following storms and up to 5 mm d-1 on the receding limb of floods. The groundwater pulses are likely produced by activation of local groundwater flow paths by water ponding on the surrounding flood plains. While 222Rn is a sensitive tracer for quantifying transient groundwater discharge, the mass-balance used to estimate fluxes is sensitive to parameterisation of gas exchange (k) with the atmosphere. Comparison of six equations for calculating k showed that, based on parameterisation of k alone, the groundwater flux estimate could vary by 58%. This work shows that neglecting transient processes will lead to errors in water and solute flux estimates based on infrequent point measurements. This could be particularly important for surface waters connected to contaminated or saline groundwater systems.
Further data
Item Type: | Article in a journal |
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Refereed: | Yes |
Additional notes: | BAYCEER129099 |
Institutions of the University: | Research Institutions Research Institutions > Research Centres Research Institutions > Research Centres > Bayreuth Center of Ecology and Environmental Research- BayCEER Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Earth Sciences > Chair Hydrology Research Institutions > Research Units > Limnological Research Station Faculties Faculties > Faculty of Biology, Chemistry and Earth Sciences Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Earth Sciences Research Institutions > Research Units |
Result of work at the UBT: | Yes |
DDC Subjects: | 500 Science |
Date Deposited: | 01 Aug 2016 10:59 |
Last Modified: | 04 Aug 2022 06:58 |
URI: | https://eref.uni-bayreuth.de/id/eprint/33743 |