Effects of elevated production of autochthonous dissolved organic matter on the freely dissolved concentration of cadmium

Eutrophication enhances the production of autochthonous dissolved organic matter (DOM), which is a major driving factor behind the impairment of many aquatic ecosystems. In a mesocosm study, we investigated the effects of the abundance and composition of DOM on the potential bioavailability of cadmium (Cd) caused by eutrophication, using three-dimensional excitation-emission matrix fluorescence spectroscopy integrated with tangential flow ultrafiltration technology. The complexing capacity of DOM-Cd and the sorption distribution coefficient between DOM and the bulk solution was calculated based on a 1 : 1 complexation model. The fluorescent DOM was decomposed into three components (one prot…