A study of spatial scaling in suspended sediment yield along a rural river system — the River Eden, Cumbria, UK

摘要

Specific suspended sediment yield was calculated for sub-catchments at a range of scales within the Eden catchment, northwest England. Suspended sediment load was calculated using the flow duration/sediment rating curve method. Specific sediment yield did not show a significant relationship with catchment area, but was found to be spatially variable, particularly between smaller catchments. In order to explain the observed pattern, spatial analysis of catchment characteristics thought to influence sediment yield was carried out. Some variables were derived from GIS data; others were surveyed in the field. No individual variables had a significant relationship with specific sediment yield, suggesting that the factors affecting sediment yield are complex. However, no variables had a significant relationship with catchment area either, indicating the complex nature of the catchment morphology. It is suggested that the catchment area—sediment yield relationship provides a poor basis for understanding spatial variability in sediment yield because of the variability in the underlying processes both within and between catchments. An alternative method of conceptualising spatial variability in sediment yield is now being developed.