Peatlands near Impfondo, RoC. Credit: Simon Lewis
Why did the peatland develop?
Initial radiocarbon dating at the base of the peat – up to six metres below the surface – has revealed that the peatland began to form about 10,000 years ago – when Central Africa became warmer and wetter as the Earth emerged from the last Ice Age. It is likely that these conditions contributed to the subsequent peat growth.
To build on this initial finding, we will take cores of peat and analyse them using a suite of long term environmental proxies. Peat provides a unique archive of the past environment, like a time capsule, it contains tiny microscopic artefacts that we can look at to give us an insight into the past.
Led by Dr Ian Lawson and Dr Donna Hawthorne from the University of St Andrews, the analysis will use ancient preserved pollen grains trapped in the peat to reconstruct the past vegetation of the region. Analysis of tiny single-celled organisms (called testate amoebae) from the peat core can provide an indicator of how wet the peatland was in the past. Also isolating charcoal fragments from the peat column can give us an idea of how frequent fires were in the past and how big.
Prof Susan Page and Dr Arnoud Boom from the University of Leicester will then undertake further analysis of “markers”, such as the chemical composition of wax left on the surface of semi-decomposed leaves preserved in the peat. These markers provide records of changes in temperature and rainfall over time – allowing us to reconstruct the past climate of the region.
This research will enable us to discover how the peatland formed and how it has developed over time, how past changes in rainfall and temperature have affected the accumulation or release of carbon in the peatland – and begin to understand how stable the peatland could be under present and future climatic conditions.