An assessment of HgII to preserve carbonate system parameters in organic-rich estuarine waters

This work assesses the effectiveness of sample preservation techniques for measurements of pH_T (total scale), total dissolved inorganic carbon (C_T), and total alkalinity (A_T) in organic-rich estuarine waters as well as the internal consistency of measurements and calculations (e.g., A_T, pH_T, and C_T) in these waters. Using mercuric chloride (HgCl₂)-treated and untreated water samples, measurements of these carbonate system parameters were examined over a period of 3 months. Respiration of dissolved organic matter in untreated samples created large discrepancies in C_T concentrations (~37 μmol kg⁻¹ increase, p