Table 1 Range of physical-chemical and biological properties of surface waters in Tagus estuary for each sampling date. Freshwater flow (Q), salinity (S), temperature (T), suspended particulate matter (SPM), chlorophyll a (Chl a), dissolved oxygen (DO), total alkalinity (TA), dissolved inorganic carbon (DIC) and CO2 partial pressure (pCO2).

From: Inorganic carbon distribution and CO2 fluxes in a large European estuary (Tagus, Portugal)

Season Sampling dates Q a (m3 s−1) S T (°C) SPM (mg l−1) Chl a (mg m−1) DO (%) pH TA (µmol kg−1) DIC (µmol kg−1) pCO2 (µatm)
Summer September 1999b 33 4.66–36.00 14.1–22.0 16.4–39.6 1.5–14.4 79–106 7.23–7.91 2307–3381 2409–3323 922–4575
Spring May 2000 376 0.17–26.96 17.8–20.8 6.1–71.3 1.0–13.5 82–103 7.82–7.88 1401–3535 1421–3455 906–1592
Winter March 2001 1861 0.09–12.50 13.0–14.6 19.6–164.7 0.7–3.1 66–104 7.63–7.92 977–1834 1016–1816 873–1998
Summer July 2001b 130 0.24–35.10 16.1–24.7 7.8–42.3 3.2–13.0 93–126 7.91–8.01 1918–2827 1954–2666 714–1326
Summer June 2002b 81 0.31–34.27 17.7–24.3 28.6–135.0 1.4–40.1 87–104 7.70–8.23 2573–3330 2587–3270 1012–2779
Spring May 2003b 233 0.20–34.12 16.6–23.4 5.7–62.0 1.6–31.8 85–107 7.54–7.94 1751–2784 1875–2672 851–3778
Winter February 2004 264 0.18–23.51 12.7–15.7 11.5–64.5 0.2–2.6 78–91 7.13–8.05 1447–2792 1476–2639 662–9160
Spring May 2006b 125 0.58–33.76 17.7–21.8 37.9–116.3 1.0–73.4 89–114 7.77–8.25 1418–3382 1422–3145 487–2704
Autumn November 2006 768 0.21–32.39 17.7–19.0 32.3–56.8 0.2–1.1 72–90 7.35–7.90 1757–2884 1915–2717 1058–4552
Spring May 2007b 86 9.81–35.23 14.8–20.9 12.0–45.0 1.4–9.4 82–101 7.89–8.05 2371–2528 2269–2366 620–970
  1. aTagus river flow, taken from Almourol station (the most downstream hydrological station, ~85 km upstream the estuary mouth). On-the-spot water discharge data was not available. Values were obtained from the Portuguese Environment Agency (APA, I.P.) accessed in a public database (http://snirh.apambiente.pt/)
  2. bUpwelling was present at the adjacent coastal shelf.