The pollen record of Empertrum nigrum in southern Pennine peats: implications for erosion and climate change
1997
Tallis, J.H.
1 Records of Empetrum nigrum pollen from blanket peat profiles at 18 sites in the southern Pennines, covering a variety of topographic situations, were collated. Inferences were drawn from the pollen database about climatic change over the last 3000 years and the time of onset of gully erosion of the peats. 2 Interpretations of the pollen record were based on observations of the present-day distribution of E. nigrum in British blanket mires, and on studies by surface-sample analysis of its pollen production and dispersal at a North Wales bog. Empetrum favours better-drained situations such as hummocks and gully sides, and its pollen is dispersed only over short distances. Pollen was found in quantity only at one hummock site. 3 Two episodes of high Empetrum pollen were found consistently in the peat profiles: prior to about 860 BC, and between c. AD 1100 and 1250. These episodes were interpreted as the product of extended periods of drier climate. At sites exhibiting severe gully erosion at the present day, high Empetrum pollen values have been maintained subsequent to AD 1250; sites along the middle and upper reaches of erosion gullies, however, show high values only within the last 200-250 years. 4 Because of the sensitivity of the southern Pennine bog vegetation to climatic change, the stratigraphic record of Sphagnum and Racomitrium macrofossils, in combination with the Empetrum pollen record, can be used to provide a framework of climatic change in the region over the last 3000 years.
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