Short-term changes of climate and vegetation revealed by pollen analysis of hyrax dung in South Africa

A pollen sequence in a relatively young hyrax dung midden in the Orange Free State, South Africa, shows marked changes in composition which can be related to environmental fluctuations. The midden from Clarens was dated by radiocarbon to the last thirty years on the basis of recent radiocarbon concentration levels of the atmosphere, which were artificially increased by extensive nuclear arms testing after 1954. Fluctuations in the pollen contents of the dung sequence conform with recent vegetation changes between 1947 and 1990, which are revealed by a series of air and other photographs. Details of the fluctuating pollen sequence can further be interpreted in terms of short-term meteorological changes which have been recorded at a nearby weather station in Bethlehem, Orange Free State, and in terms of the effects of stock grazing on vegetation of the area.