Article (Scientific journals)
Calibration of hydroclimate proxies in freshwater bivalve shells from Central and West Africa
Kelemen, Z.; Gillikin, D. P.; Graniero, L. E. et al.
2017In Geochimica et Cosmochimica Acta, 208 (0), p. 41-62
Peer Reviewed verified by ORBi
 

Files


Full Text
1-s2.0-S001670371730176X-main.pdf
Publisher postprint (3.42 MB)
Download

All documents in ORBi are protected by a user license.

Send to



Details



Keywords :
Freshwater bivalve shells; Hydroclimate; Niger; Oubangui; Stable isotopes; Niger River; Ubangi River; Bivalvia; Unionidae
Abstract :
[en] Freshwater bivalve shell oxygen and carbon stable isotope ratios (δ18O, δ13C) may act as recorders of hydroclimate (e.g., precipitation-evaporation balance, discharge) and aquatic biogeochemistry. We investigate the potential of these hydroclimate proxies measured along the growth axis of shells collected from the Oubangui River (Bangui, Central African Republic) and the Niger River (Niamey, Niger). Biweekly water samples and in situ measurements collected over several years, along with daily discharge data from both sites allowed a direct comparison with proxies recorded in the shells. Data from a total of 14 unionid shells, including three species (Chambardia wissmanni, Aspatharia dahomeyensis, and Aspatharia chaiziana), confirmed that shells precipitate carbonate in oxygen isotope equilibrium with ambient water. Because water temperature variations were small, shell δ18O values (δ18Oshell) also accurately record the seasonality and the range observed in water δ18O (δ18Ow) values when calculated using an average temperature. Calculated δ18Owvalues were in good agreement over the entire record of measured δ18Owvalues, thus δ18Oshellrecords can be reliably used to reconstruct past δ18Owvalues. Discharge and δ18Owvalues from both rivers fit a logarithmic relationship, which was used to attempt reconstruction of past hydrological conditions, after calculating δ18Owvalues from δ18Oshellvalues. A comparison with measured discharge data suggests that for the two rivers considered, δ18Oshelldata are good proxies for recording discharge conditions during low(er) discharge levels, but that high discharge values cannot be accurately reconstructed due to the large scatter in the discharge-δ18Owrelationship. Moreover, periods of bivalve shell growth cessation due to high turbidity or air exposure should be taken into account. While δ13C values of dissolved inorganic carbon in both rivers showed clear seasonality and correlated well with discharge, most of the shells analyzed did not record these variations adequately, likely due to the complication of vital effects including the variable contribution of metabolic CO2. Thus, tropical African unionid δ18Oshellvalues can be used to reconstruct δ18Owvalues with high confidence to provide insight on past hydroclimate such as precipitation-evaporation balance and periods of low discharge. © 2017 Elsevier Ltd
Research center :
FOCUS - Freshwater and OCeanic science Unit of reSearch - ULiège
KU Leuven - Katholieke Universiteit Leuven
FWO - Fonds Wetenschappelijk Onderzoek Vlaanderen
IAEA - International Atomic Energy Agency
Disciplines :
Aquatic sciences & oceanology
Author, co-author :
Kelemen, Z.;  Department of Earth & Environmental Sciences, KU Leuven, Celestijnenlaan, 200E, Leuven, Belgium, Department of Geology, Union College, 807 Union St., Schenectady, NY, United States
Gillikin, D. P.;  Department of Geology, Union College, 807 Union St., Schenectady, NY, United States
Graniero, L. E.;  Department of Geology, Union College, 807 Union St., Schenectady, NY, United States, Department of Geological Sciences, University of North Carolina Chapel Hill, 104 South Road, Chapel Hill, NC, United States
Havel, H.;  Department of Geology, Union College, 807 Union St., Schenectady, NY, United States
Darchambeau, François ;  Université de Liège > Département d'astrophys., géophysique et océanographie (AGO) > Chemical Oceanography Unit (AGO)
Borges, Alberto  ;  Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Chemical Oceanography Unit (AGO)
Yambélé, A.;  Service de I'Agrométéorologie et de Climatologie, Direction de la Météorologie Nationale, Bangui, Central African Republic
Bassirou, A.;  Département des Sciences de la Vie et de la Terre, Université Abdou Moumouni, Niamey, Niger
Bouillon, S.;  Department of Earth & Environmental Sciences, KU Leuven, Celestijnenlaan, 200E, Leuven, Belgium
Language :
English
Title :
Calibration of hydroclimate proxies in freshwater bivalve shells from Central and West Africa
Publication date :
2017
Journal title :
Geochimica et Cosmochimica Acta
ISSN :
0016-7037
eISSN :
1872-9533
Publisher :
Elsevier Ltd
Volume :
208
Issue :
0
Pages :
41-62
Peer reviewed :
Peer Reviewed verified by ORBi
European Projects :
FP7 - 240002 - AFRIVAL - African river basins: catchment-scale carbon fluxes and transformations.
Name of the research project :
ERC Starting Grant 240002, AFRIVAL; research project G.0D87.14N; NSF-MRI #1229258; National Geographic Society Research and Exploration Grant (#8885--11)
Funders :
KU Leuven - Katholieke Universiteit Leuven [BE]
CER - Conseil Européen de la Recherche [BE]
RSCA - Research Corporation for Science Advancement [US]
FWO - Fonds Wetenschappelijk Onderzoek Vlaanderen [BE]
CE - Commission Européenne [BE]
Available on ORBi :
since 22 February 2018

Statistics


Number of views
75 (4 by ULiège)
Number of downloads
265 (1 by ULiège)

Scopus citations®
 
30
Scopus citations®
without self-citations
24
OpenCitations
 
28

Bibliography


Similar publications



Contact ORBi