Table 2.

Biogeochemical Processes and Their Impact on Charge Balance Alkalinity (ΔCBA) and Titration Alkalinity (ΔTA) (After Soetaert et al., 2007)

Process	Reaction	ΔCBA	ΔTA
(R1) Aerobic Mineralization	(CH2O)(NH3)n(H3PO4)p + O2 → CO2 + n NH3 + p H3PO4 + H2O	0	n ‐ p
(R2) Denitrification	(CH2O)(NH3)n(H3PO4)p + 0.8 HNO3 → CO2 + n NH3 + p H3PO4 + 0.4 N2 + 1.4 H2O	0	0.8 + n − p
(R3) Mn‐Oxide Reduction	(CH2O)(NH3)n(H3PO4)p + 2 MnO2 + 4H+ → CO2 + n NH3 + p H3PO4 + 2 Mn2+ + 3H2O	4	n − p + 4
(R4) Fe‐Oxide Reduction	(CH2O)(NH3)n(H3PO4)p + 2 Fe2O3 + 8H+ → CO2 + n NH3 + p H3PO4 + 4 Fe2+ + 5H2O	8	n − p + 8
(R5) Sulfate Reduction	(CH2O)(NH3)n(H3PO4)p + 0.5 H2SO4 → CO2 + n NH3 + p H3PO4 + 0.5 H2S + H2O	0	n − p + 1
(R6) Methanogenesis	(CH2O)(NH3)n(H3PO4)p → 0.5 CO2 + n NH3 + p H3PO4 + 0.5 CH4 + H2O	0	n − p
(R7) Nitrification	NH3 + 2 O2 → HNO3 + H2O	0	−2
(R8) Annamox	NH3 + HNO2 → N2 + H2O	0	0
(R9) Aerobic Oxidation of Methane	CH4 + O2 → CO2 + 2 H2O	0	0
(R10) Anaerobic Oxidation of Methane	CH4 + H2SO4 → CO2 + H2S + 2 H2O	0	2
(R11) Calcite Precipitation	Ca2+ + CO3 2− → CaCO3	‐2	−2
(R12) Primary Production (Nitrate)	CO2 + n HNO3 + p H3PO4 + (1 + n) H2O → (CH2O)(NH3)n(H3PO4)p + (1 + 2n) O2	0	p + n
(R13) Primary Production (Ammonium)	CO2 + n NH3 + p H3PO4 + H2O → (CH2O)(NH3)n(H3PO4)p + O2	0	p − n
(R14) CO2 Emission to Air	CO2 → CO2 (g)	0	0
(R15) Proton Sorption	H+ → H+‐surface	1	1
(R15) Ammonium sorption	NH4 + → NH4 +‐surface	1	0

Note. n = N/C ratio of organic matter and p = P/C ratio of organic matter.