Solute transport as an indicator of morphodynamic zonation in a postglacial environment, West Pomerania, Poland

Abstract

Variations in the chemistry of dissolved sediment transported fluvially reflect the dynamics of soil leaching and erosion in the catchment. In this study, spatial changes in the concentrations of selected chemical parameters of surface waters have been used as natural geochemical indicators of variability in the chemical denudation processes operating in a postglacial catchment with a temperate climate. Hydrochemical mapping, supplemented by hydrological mapping, has been used to analyse the sources and hydrological pathways of solutes in the catchment. The field research was conducted in a small catchment drained by the Kluda River, Poland. This is a part of the upper Parseta hydrographic system, which is considered to be representative of the postglacial lakeland zone of West Pomerania and the Polish Plain. The study is based on hydrological and hydrochemical data from the period 1990–1993. Variations in the physical and chemical parameters of those waters reveal considerable differences in surface water properties in the catchment. A grouping procedure and principal components analysis carried out on the basis of 10 physico-chemical parameters characterizing the measurement sites produced four hydrochemical groups. The results emphasize that the physico-chemical properties of the surface water depend not only on spatial variability in catchment lithology, soils, land use and topography, but also the contact time and pathways by which water reaches the drainage network. Hydrological pathways in the slope system and their importance to the supply of solutes to the channel system provided a basis for distinguishing four morphodynamic zones (divide, plateau, escarpment and valley) in the Kluda catchment. The contributions of water and solutes to the river channel from these morphodynamic zones are distinctly different. Copyright © 1999 John Wiley & Sons, Ltd.