[en] Currently, the lack of robust, context-distributed subsurface greenhouses gases (GHG) concentrations data is a key bottleneck to reduce the uncertainty range of GHG groundwater input to continental surface water bodies such as rivers or lakes estimates. Carbon dioxyde (CO2), methane (CH4) and nitrous oxyde (N2O) are likely to be indirectly transferred to the atmosphere through groundwater discharge into continental surface water bodies. We aim to extend regional-scale estimates of indirect GHG emissions by screening, in numerous hydrogeological (such as alluvial, sandstone, chalk and limestone aquifers) and land use contexts (such as industrial and agricultural), the occurence of these gases. Here, we report and discuss CO2, CH4 and N2O concentrations from an initial survey conducted over selected sites (n= 40) within shallow (0-100 m depth) aquifers in Wallonia (Belgium) for the first time. The preliminary results obtained in this study show that the range of GHG concentrations varies between 5160 and 47544 ppm, 0 and 1064 nmol.L-1, as well as 1 and 5637 nmol.L-1 for the partial pressure of CO2, CH4 and N2O respectively. This new and unique regional dataset provides a first step in developping a refined understanding of favorable contexts for GHG occurence in groundwater which may be used to reduce the uncertainties related to indirect emissions of GHG through groundwater-surface water transfers.
Research Center/Unit :
Aquapôle - ULiège
Disciplines :
Geological, petroleum & mining engineering
Author, co-author :
Hakoun, Vivien ; Université de Liège > Département ArGEnCo > Hydrogéologie & Géologie de l'environnement
Gesels, Julie ; Université de Liège > Département ArGEnCo > Hydrogéologie & Géologie de l'environnement
Tseng, Jean Hsiao-Chun; National Sun Yat-sen University Kaohsiung (Taiwan) > Department of Oceanography
Petrovic, Sandro ; Université de Liège > Département d'astrophys., géophysique et océanographie (AGO) > Océanographie chimique
Dassargues, Alain ; Université de Liège > Département ArGEnCo > Hydrogéologie & Géologie de l'environnement
Borges, Alberto ; Université de Liège > Département d'astrophys., géophysique et océanographie (AGO) > Océanographie chimique
Brouyère, Serge ; Université de Liège > Département ArGEnCo > Hydrogéologie & Géologie de l'environnement
Language :
English
Title :
Regional occurence of greenhouses gases in groundwater: Initial results in shallow Belgian aquifers.
Publication date :
September 2015
Number of pages :
électronique
Event name :
42nd IAH International Congress, AQUA2015
Event organizer :
Marco PETITTA Alessandro GARGINI Daniela DUCCI Fulvio CELICO Others
Event place :
Rome, Italy
Event date :
du 13 septembre au 18 septembre 2015
Audience :
International
Funders :
F.R.S.-FNRS - Fonds de la Recherche Scientifique [BE]