Dissolved inorganic carbon dominant species

Fig. 5.5 Relationship between the total dissolved inorganic carbon species (TDIC i.e. H2C03 + HCOj + COj ) and pH. Most natural waters have pH between 7 and 9 where the HC03 anion is abundant (>80% of the TDIC). In highly alkaline waters (pH > 10.3) the COf anion becomes dominant, while in acidic waters (pH <6.4) the undissociated acid (H2C03) is the dominant TDIC species.

Data from anchor stations 13 and 20 indicated that HGO was the dominant form of dissolved inorganic carbon species during the investigated 48 h, followed by GO and GOg in sequence. For station 13, differences in the ratio of HGOg to DIG between the two layers were not distinct. It was the same for GOg and GOg. Their differences between the five layers of station 20 were much bigger than that at station 13, perhaps because the former was much deeper than that the latter, leading to the inhomogeneous distribution... 

---