Vegetation history inferred from pollen in Late Quaternary faecal deposits (hyraceum) in the Cape winter-rain region, and its bearing on past climates in South Africa

Abstract

Pollen analysis shed light on vegetation community structure over the last 23,000 year in the Western Cape. The pollen from dated hyrax faecal accumulations (hyraceum) relates to the evolution of climate and contributes to proxy records in southern Africa. Principal components analyses of the pollen data and d13C values of the hyrax dung samples show millennial and shorter scale temperature, moisture and seasonality variations in the winter rain region. The moisture availability at times do not parallel that in previously studied proxy records in the summer rain region showing an asynchronous moist event in the early Holocene and drier conditions in the Middle Holocene. Anomalies in climate between the two regions may depend on the degree of northward or southward shifting of winter- and summer-rain circulation systems. Scenarios with winter-rain or cool growing seasons mostly typify the dung sequence but do not exclude the possibility of southward displacement of the westerly belt under precessional strength with slight summer rain increases during the Last Glacial Maximum. Limited southward displacement is also possible during the Mid Holocene.