A multifactor exploration of the photobleaching of Suwannee River dissolved organic matter across the freshwater/saltwater interface.

A four factor central composite experimental design was applied to explore the photobleaching of Suwannee River dissolved organic matter (SRDOM) at 350 nm as a function of the tetravariate system of [SRDOM], total [Fe(III)], [NO3-], and salinity. The ranges of each factor were setto cover their likely concentrations atthe freshwater/ saltwater interface, to encompass the possible conditions encountered during the transition from the terrestrial to marine environment. Each experiment was carried out using a minimum of 25 different initial conditions, with 3-6 replicates/condition.