Summary: | Methods/devices for discrete water samples: AT and CT were measured with a VINDTA 3C system (Versatile instrument for the determination of total dissolved inorganic carbon and titration alkalinity), coupled with a UIC CO2 coulometer (model CM5015) and a METROHM© Titrino (model 716 DMS). Instruments were calibrated with Dickson Certified Reference Material (Batch 127). The fCO2, pH and aragonite saturation state (Ωa) were calculated with CO2SYS as a function of measured parameters (AT, CT, salinity, nutrients and SWT), with dissociation constants of Mehrbach et al. (1973) for carbonic acid as refit by Dickson and Millero (1987), and Dickson (1990) for boric acid. Five inorganic nutrients were measured through a reagent based method with a Lachat′sQuikChem© 8500 Series 2 Flow Injection Analysis (FIA) System, following the Standard Operation Procedure from Centro de Investigación en Ciencias del Mar y Limnología (CIMAR) of the University of Costa Rica (PON Nut-08).
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