Middle and Late Holocene paleolimnological changes in central Lake Tanganyika

Integrated evidence from the Kavala Island Ridge (Tanzania)

Bibliographic Data

ID12267717
AuthorsLeandro Domingos Luz (0000-0001-8477-1010, University of Kentucky, corresponding author), Michael J Soreghan (0000-0002-2424-0194, University of Oklahoma), Giliane Géssica Rasbold (0000-0001-7375-6261, University of Kentucky), Geoffrey S Ellis (0000-0003-4519-3320, Central Energy Resources Science Center), Justin E Birdwell (0000-0001-8263-1452, Central Energy Resources Science Center), Ismael A Kimirei (0000-0002-1101-5262, Tanzania Fisheries Research Institute), Ishmael A Kimirei (Tanzania Fisheries Research Institute, Tanzania), Christopher A Scholz (0000-0002-7178-7619, Syracuse University), Michael M Mcglue (0000-0002-0725-7250, University of Kentucky)
Year2024
Volume34
Issue9
Pages1167-1180
Publication date2024-06-10
Open AccessYes
TypeARTICLE
VenueThe Holocene (JOURNAL)
Journal identifiersISSN: 0959-6836 • E-ISSN: 1477-0911
PublisherSAGE Publishing (PUBLISHER • US)
DOI10.1177/09596836241254475
OpenAlexW4399505532
LanguageEN
References cited66

Middle and Late Holocene sediments have not been extensively sampled in Lake Tanganyika, and much remains unknown about the response of the Rift Valley’s largest lake to major environmental shifts during the Holocene, including the termination of the African Humid Period (AHP). Here, we present an integrated study (sedimentology, mineralogy, and geochemistry) of a radiocarbon-dated sediment core from the Kavala Island Ridge (KIR) that reveals paleoenvironmental variability in Lake Tanganyika since the Middle Holocene with decadal to centennial resolution. Massive blue-gray sandy silts represent sediments deposited during the terminal AHP (~5880–4640 cal yr BP), with detrital particle size, carbon concentrations, light stable isotopes, and mineralogy suggesting an influx of river-borne soil organic matter and weathered clay minerals to the lake at that time. Enhanced by the AHP’s warm and wet conditions, chemical weathering and erosion of Lake Tanganyika’s watershed appears to have promoted considerable nutrient recharge to the lake system. Following a relatively gradual termination of the AHP over the period from ~4640 cal yr BP to ~3680 cal yr BP, laminated and organic carbon-rich sediments began accumulating on the KIR. δ 15 N bulk , C/N, and hydrogen index data suggest high relative primary production from a mix of algae and cyanobacteria, most likely in response to nutrient availability in the water column under a cooler and seasonally dry climate from ~3680 to 1100 cal yr BP. Sediments deposited during the Common Era show considerable variability in magnetic susceptibility, total organic carbon content, carbon isotopes, and C/N, consistent with dynamic hydroclimate conditions that affected the depositional patterns, including substantial changes around the Medieval Climate Anomaly and Little Ice Age. Data from this study highlight the importance of sedimentary records to constrain boundary conditions in hydroclimate and nutrient flux that can inform long-term ecosystem response in Lake Tanganyika

Geochemistry · Geography · Holocene · Hydrology (agriculture · Paleolimnology · Physical geography · Radiocarbon dating · Sediment · Sedimentology · Total organic carbon · Weathering · Aquatic Ecosystems and Biodiversity · Geology and Paleoclimatology Research · Isotope Analysis in Ecology · Ecology · Geology · Oceanography · Paleontology

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