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The regulation of dissolved trace metal concentration in major scottish estuaries - an applied field and lab study - AE0211

R&D Summary Objectives:- To produce a predictive model to describe the interactions between metals and suspended particulate materials in estuaries. Key customer purpose:- Provide MAFF & SOAFD with an accurate assessment of the environmental risk posed by inputs to estuarine systems from industrial, domestic and agricultural sources, and improve the targeting of resources in environmental monitoring work.
Present efforts to develop predictive models of the behavi our and fate of metals in estuarine zones are confounded by the lack of understanding of the type and rates of chemical reactions involving dissolved metals, dissolved organic compounds and suspended particulate material (SPM), of both natural and anthropogenic origin. In addition, the sampling frequency is normally insufficient to consider the more dynamic aspects of the estuarine environment, such as semi-diurnal tidal cycles, spring-neap cycles etc.. We therefore aim to:- 1 Assess the extent to which SPM-trace metal interactions are influenced by the chemistry of the aqueous phase (e.g. salinity, pH, metal concentration, Eh, etc.), the particle type and the size distribution of SPM. We will focus our efforts on 3 trace metals (Pb, Cd, and Cu) which have contrasting adsorption behaviours. 2. Develop a physico-chemical model of trace metal sorption, based on a series of equilibrium and rate constants (or functions) appropriate for estuarine conditions in the Clyde, Tay and Forth estuaries, and with the potential for use in other estuarine systems. The estuaries in the proposed study have been selected on the basis of their differing SPM loads and degree of contamination. Recent studies in these estuaries ensure that reliable trace metal data is available for experimental design. 3. Conduct a sampling programme at a sufficient frequency to characterise the processes of trace metal uptake and release.
Time-Scale and Cost
From: 1992

To: 1996

Cost: £203,543
Contractor / Funded Organisations
University - Southampton
Environmental monitoring              
Environmental Protection              
Water quality monitoring              
Fields of Study
Environmental Protection - Marine