Nutrient Budgets for a Dry Heath Ecosystem in the South of England

Abstract

The heathlands of southern Britain, with vegetation dominated by Calluna vulgaris, are found on soils of low fertility where factors such as grazing, exposure or fire, operate to prevent the establishment of tree species. Unlike the other factors, fire periodically removes the standing crop and much of the accumulated litter. The magnitude of the nutrient fund in the heather ecosystem and the losses of nutrients due to heather burning in Scotland and Northern England have been described by Robertson & Davies (1965) and Allen (1964). Little or no similar work has been published from heathland areas in southern Britain. In this paper, the processes of vegetation development and litter accumulation on an area of lowland heath in southern Britain are described and the status of older stands of Calluna are discussed. The areas of heathland to be described occur on soils derived from Bagshot sands in the Poole basin of Dorset. These heathlands were once a western extension of the New Forest heathlands (Moore 1962), but urban development has led to their separation from the main New Forest area. With this separation have come other changes in land use, an almost complete reduction of agricultural grazing, cessation of controlled burning if it ever existed and an end to the cutting of peat and furze (Ulex europaeus) for fuel and other purposes. It is suggested by Seagrief (1959) from his Wareham pollen diagrams, that the history of heathland in this area may extend back as far as early Atlantic times.