Holocene 1 (1)

Exposures in blanket mire deposits in the Galloway Hills, southwest Scotland, have revealed the presence of minerogenic layers within the peat stratigraphy. These deposits are studied by a variety of methods with a view to the investigation of ecological influences upon deposition, the timing of events and aspects of their geomorphology. The layers were deposited under both wooded and unwooded conditions in the vicinity of the sites, but vegetational disturbances consistent with anthropogenic activity including agriculture were coeval with minerogenic deposition at various times. The evidence points to a dissimilarity in the formation times of individual layers of pronounced minerogenic deposition, although deposition has been a continuous event over the last five thousand years. Au(abr)

The evidence for enhanced erosion in upland Britain during the Late Holocene is evaluated. Though there is widespread evidence for recent soil erosion on high plateaux, this has not been precisely dated. Radiocarbon dating confirms the occurrence of Late Holocene solifluction (gradual movement of wet soil etc down slope) on high ground, but at only one site has evidence been found for recent accelerated activity. Several areas, however, have yielded evidence of Late Holocene debris cone accumulation, and parts of the Scottish highlands experienced a drastic increase in debris flow activity over the past few centuries. Climatic deterioration and vegetation degradation resulting from overgrazing or burning are frequently cited as the causes of enhanced erosion, but cause and effect are often related only by coincidence of timing. In consequence, only circumstantial evidence links erosion with climatic deterioration, though anthropogenic influences have been more firmly established at a few sites. The role of extreme events in initiating phases of upland erosion is uncertain. Au