Dynamic response characteristics of the plynlimon catchments and preliminary analysis of relationships to physical descriptors

Regionalization methodology proposed for the assessment of hydrological change on a regional or national-scale was examined using 8 Plynlimon catchments in central Wales, for which there were good hydrological and physical descriptor records. Relationships between the dynamic response characteristics (DRC) and physical catchment descriptors (PCD) such as soil type, slope and area were examined. Inter-catchment relationships between PDC and DRC for the 1980-1981 linear module were generally confirmed by the 1982-1983 calibrations. Correlation of some PCD complicated the qualitative analysis of the relationships. Correlation problems could be helped by quantitative analyses, such as principal component analysis. In this study there were too few data points for its application but such methods would be useful when many, more and varied catchments had been modelled. With the provision of PCD data, relationships found might then be extrapolated to determine the hydrology of ungauged catchments.