Dissolved Organic Matter Quality in a Shallow Aquifer of Bangladesh: Implications for Arsenic Mobility.

摘要: In some high arsenic (As) groundwater systems, correlations are observed between dissolved organic matter (DOM) and As concentrations, but in other such relationships absent. The role of labile DOM as the main driver microbial reductive dissolution is not sufficient to explain variation DOM–As relationships. Other processes that may also influence mobility include complexation by humic substances, competitive sorption electron shuttling reactions mediated humics. To evaluate influences, we characterized optical properties filtered surface water (n = 10) 24) samples spanning an age gradient Araihazar, Bangladesh. Further, analyzed large volume fulvic acid (FA) isolates 6) for properties, C N content, 13C NMR spectroscopic distribution. Old (>30 years old) contained primarily sediment-derived had significantly higher (p < 0.001) concentration than ground...