Use of a kinetic bio-assay procedure to estimate sulphate and cysteine concentrations in sediment

The problems involved in determining the bio-availability of nutrients in aquatic sediments are outlined, and results are presented of studies on the use of a kinetic bio-assay method, developed by R. T. Wright and J. E. Hobbie in 1966, to confirm the concentration of hydrogen sulphide precursors determined by standard analytical procedures. The kinetic bio-assay procedure is outlined. Although the results obtained were inconclusive, they suggested that production of sulphide by sulphate reduction and putrefaction followed the Michaelis-Menten kinetic model. This approach was useful in estimating substrate availability for sulphate and cysteine, and could be used in tracer estimates of sulphide production in water with a low sulphate content.