Article (Scientific journals)
Freshwater bivalve shells as hydrologic archives in the Congo Basin
Kelemen, Z; Gillikin, DP; Borges, Alberto et al.
2021In Geochimica et Cosmochimica Acta, 308 (0), p. 101-117
Peer Reviewed verified by ORBi
 

Files


Full Text
Kelemen_et_al_2021.pdf
Publisher postprint (2.89 MB)
Download

All documents in ORBi are protected by a user license.

Send to



Details



Abstract :
[en] We test the applicability of bivalve shell oxygen isotope composition to reconstruct hydrological dynamics in four riverine sites in the Congo River basin. Twenty-three specimens from the Unionoida order were collected from locations where long-term discharge data are available, and in situ measurements and water samples were collected over several years. Due to the highly variable (species-specific) shell morphology, various sampling techniques were used to analyze the shell sections; however, every specimen recorded the seasonality of the host water oxygen stable isotope composition (δ 18 O w ) in its δ 18 O shell record. Discharge data showed an inverse relationship with δ 18 O w values, which was well described with a logarithmic fit. An exception was the Kasai River, where the δ 18 O w record shows an additional peak occurring during the high discharge period, which renders the discharge-δ 18 O w relationship more complex than in the other systems investigated. Low ratios of maximum to minimum discharge (Q max /Q min ) were found to result in a low δ 18 O w amplitude, which was reflected as low δ 18 O shell variability. The Congo and Kasai rivers had Q max /Q min ratios ~2 to 2.5, while the Oubangui showed a much higher Q max /Q min (~19). Shells correspondingly showed a large δ 18 O shell range (amplitude between 2.4 and 5.0‰) for individual Oubangui shells, and lower amplitude for other sites (1.0 to 2.2‰). Thus, shells have a high resolving power to be used to record hydrological variability, since long-term changes in precipitation pattern, discharge, land-use change, or other hydrological changes have an influence on δ 18 O w values. Shells with wide range of δ 18 O values reflect high seasonal variability in rivers, while shells with lower δ 18O amplitude correspond to sites with more steady river conditions over the year. Our study illustrates that fossil shell δ 18 O values could indicate Q max /Q min values in ancient African river systems.
Research center :
FOCUS - Freshwater and OCeanic science Unit of reSearch - ULiège
Disciplines :
Aquatic sciences & oceanology
Author, co-author :
Kelemen, Z
Gillikin, DP
Borges, Alberto  ;  Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Chemical Oceanography Unit (COU)
Tambwe, E
Sembaito, AT
Mambo, T
Nlandu Wabakhangazi, J
Yambélé, A
Stroobandt, Y
Bouillon, S
Language :
English
Title :
Freshwater bivalve shells as hydrologic archives in the Congo Basin
Publication date :
19 June 2021
Journal title :
Geochimica et Cosmochimica Acta
ISSN :
0016-7037
eISSN :
1872-9533
Publisher :
Elsevier, United Kingdom
Volume :
308
Issue :
0
Pages :
101-117
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 :
AFRIVAL
Funders :
CE - Commission Européenne [BE]
Available on ORBi :
since 12 May 2021

Statistics


Number of views
66 (8 by ULiège)
Number of downloads
168 (7 by ULiège)

Scopus citations®
 
3
Scopus citations®
without self-citations
3
OpenCitations
 
0

Bibliography


Similar publications



Contact ORBi