LAKE SEDIMENT RECORDS OF EROSIONAL PROCESSES

Accumulations of sediment at the beds of lakes, estuaries and reservoirs provide partial records of materials transported from the surrounding water catchment areas. Physical, chemical, biological and magnetic analyses, with data for accumulation rates, have been used in a range of environmental settings to infer the rate, form, cause and source of erosion. This paper is a brief review of these studies from a hydrological perspective, setting sediment studies within a lake-catchment system. The need for long term erosional records is discussed in terms of the type of erosional data which may be obtained. Alternative approaches to studying short and long term erosion are assessed with regard to their cost-effectiveness and their levels of precision and accuracy. Finally, some suggestions are made about how these erosion records may be used to model hydrological, pedological and geomorphological processes, thus linking together long term, short term and contemporary timescales of process operation.