THE POLLEN RECORD OF EMPETRUM-NIGRUM IN SOUTHERN PENNINE PEATS - IMPLICATIONS FOR EROSION AND CLIMATE-CHANGE

1 Records of Empetrum nigrum pollen from blanket peat profiles at 18 s ites in the southern Pennines, covering a variety of topographic situa tions, were collated. Inferences were drawn from the pollen database a bout climatic change over the last 3000 years and the time of onset of gully erosion of the peats. 2 Interpretations of the pollen record we re 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 fa vours 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 po llen were found consistently in the peat profiles: prior to about 860 BC, and between c. AD 1100 and 1250. These episodes were interpreted a s the product of extended periods of drier climate, At sites exhibitin g severe gully erosion at the present day, high Empetrum pollen values have been maintained subsequent to AD 1250; sites along the middle an d upper reaches of erosion gullies, however, show high values only wit hin the last 200-250 years. 4 Because of the sensitivity of the southe rn Pennine bog vegetation to climatic change, the stratigraphic record of Sphagnum and Racomitrium, macrofossils, in combination with the Em petrum urn pollen record, call be used to provide a framework of clima tic change in the region over the last 3000 years.