Late Pleistocene–Holocene Palaeoenvironmental Evolution of the Makgadikgadi Basin, Central Kalahari, Botswana: New Evidence From Shallow Sediments and Ostracod Fauna

The Makgadikgadi Basin in Botswana hosts a system of salt lakes, which developed from the Upper Pleistocene onward due to gradual shrinking giant Lake Palaeo-Makgadikgadi. Stratigraphic and palaeoclimatic studies this area are difficult influence several factors, such as complex history regional tectonic activities, well climatic changes coupled with dryland diagenetic processes. This lake, central Kalahari, is key understanding variability southern part Africa Quaternary has played an important role evolution numerous taxa, including our own. In study, detailed sedimentological analyses (grain size major elements distribution) shallow sediments Pans were combined first comprehensive study encountered ostracod fauna establish trends environmental late Quaternary. Ostracod fossil assemblages cores dominated by Limnocythere ssp., opportunistic taxa commonly colonizing littoral areas evaporative, ephemeral together subordinate occurrences Sarcypridopsis ochracea , Sclerocypris cf. bicornis, Candonopsis spp., Ilyocypris spp. pans show fluctuations Cl/K Ca/Cl ratios, often phase relative abundance suggesting cyclicity induced salinity alkalinity water. multi-proxy collected suggests Late shallow, playa lake environment strongly alkaline water, interrupted prolonged drought sustained aeolian conditions between ∼16 2 ka BP. Increasing diversity top 20–30 cm indicates that temporary shift toward higher humidity occurred around 2–1.5 BP lasted through Medieval Warm Period. humid period was followed overall desiccation trend started Little Ice Age continues until present day.