Physicochemical Processes in Aquatic Systems

Natural waters obtain their equilibrium composition through a variety of chemical reactions and physicochemical processes. In this chapter we consider principles and applications of two alternative models for natural water systems thermodynamic models and kinetic models. Thermodynamic, or equilibrium, models for natural waters have been developed more extensively than kinetic models. They are simpler in that they require less information, but they are nevertheless powerful when applied within their proper limits. Equilibrium models for aquatic systems receive the greater attention in this book. However, kinetic interpretations are needed in description of natural waters when the assumptions of equilibrium models no longer apply. Because rates of different chemical reactions in water and sediments can differ enormously, kinetic and equilibrium are often needed in the same system. 

Wilkinson, K. J. and Buffle, J. (2004). Critical evaluation of physicochemical parameters and processes for modelling the biological uptake of trace metals in environmental (aquatic) systems. In Physio chemical Kinetics and Transport at Biointerfaces, eds. van Leeuwen, H. P. and Koster, W., Vol. 9, IUPAC Series on Analytical and Physical Chemistry of Environmental Systems, Series eds. Buffle, J. and van Leeuwen, H. P., John Wiley Sons, Ltd, Chichester, UK, pp. 445-533. 

Physicochemical Parameters and Processes for Modelling the Biological Uptake of Trace Metals in Environmental (Aquatic) Systems... 

The complex spatio-temporal mosaic of habitats in alpine river systems relates to the interaction of a range of physicochemical processes, with different processes dominating the river environment at different scales. Our new approach to alpine stream classification provides a basis to conceptualise this dynamic habitat template. The contributions from the different water sources have an important influence on the aquatic habitat template for the establishment of biotic communities, particularly through the effect on physicochemical variables outlined above. These include channel stability, water temperature and sediment regimes. Where alpine streams... 

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