A 35 ka pollen and isotope record of environmental change along the southern margin of the Kalahari from a stalagmite and animal dung deposits in Wonderwerk Cave, South Africa

Abstract

A 0.6-m-long horizontal core from a stalagmite in the entrance area of Wonderwerk Cave in South Africa, a National Heritage Site, has provided a 35 ka record of environmental change. A pollen sequence from the stalagmite, and two animal dung deposits, is longer and more detailed for the end of the Pleistocene than previous palynological reports from the southern Kalahari region. This pollen record closely matches information from spring peats at Wonderkrater in Northern Province indicating that speleothem pollen can provide reliable paleovegetation data. The δ 18O and δ 13C records resemble those from Cold Air Cave in Northern Province and parallel variations in Greenland Ice Sheet GISP2 paleotemperature. This indicates that past climate changes in southern Africa were linked to changes in global atmospheric and oceanic circulation patterns possibly triggered by conditions in the North Atlantic region. The Wonderwerk data suggest wetter conditions at ca. 33 ka, from 23 to 17 ka, and from 4 ka to present. Conditions were drier 17–13 ka, when microstromatolitic carbonate was deposited on the flank of the stalagmite, and possibly also during depositional hiatuses from 33 to 23 ka and 13 to 4 ka.