Litter Accumulation Under Calluna Vulgaris on a Lowland Heathland in Britain

Abstract

The pattern of organic matter production by the above-ground vegetation of Calluna heathland in lowland Britain has been described by Chapman, Hibble & Rafarel (1975) and accounts of the overall nutrient budget and root standing crop for the same area are given by Chapman (1967, 1970). The litter layer accumulating on the surface of the soil is important as a storage bank for plant nutrients that can be released by the activity of the decomposers. In an ecosystem where available nutrients are present in limited quantities only and the rate of decomposition is low the litter layer becomes increasingly important in the overall nutrient regime of the system. The litter layer is an important habitat for members of the soil fauna, a high proportion of the biomass of the soil fauna actually living in this layer. In a potentially cyclical system, such as heathland, where the vegetation passes through building, mature and degenerate phases of development, the accumulation and characteristics of the litter layer are important regarding germination and establishment of both Calluna vulgaris (L.) Hull and invading tree and shrub species. This paper attempts to characterize the process of litter accumulation in relation to litter production, general considerations of decomposition, and the release of plant nutrients in the litter layer of an area of lowland heathland in southern Britain (in Dorset). Details of the sites under discussion have been described by Chapman (1967, 1970) and by Chapman et al. (1975).