Identifying changing fluvial conditions in low gradient alluvial archaeological landscapes: can coleoptera provide insights into changing discharge rates and floodplain evolution?

Using examples from dated alluvial deposits in the Trent basin, UK, this paper suggests that the waterlogged remains of insects, mainly beetles, can be used to detect the occurrence of varying discharge and changing patterns of flood-plain evolution in low gradient alluvial landscapes of Holocene age. This approach may provide invaluable data where the finer-grained nature of sedimentation means that other types of information such as coarse boulder berms are lacking. Comparison of Coleoptera assemblages from three high-energy and two lower-energy deposits indicates that a number of distinctive characteristics can be identified and criteria can be set for the distinction of these two contrasting depositional environments. This approach is tested using Coleoptera remains recovered from a palaeochannel fill at Spalford Meadows in the Lower Trent Valley. The application of this methodology could contribute to the reconstruction of river histories, a key factor in understanding the distribution of valley floor archaeological settlement patterns. [Copyright &y& Elsevier]