Table 6. Study comparison of averaged pCO₂ concentrations, piston velocities, CO₂ yields and estimated CO₂ fluxes.

Location	Study	pCO2(μatm)	K (cm h−1)	CO2 yield (g C m−2 per year)	CO2 flux (Tg C per year)
Malaysia	Raymond et al.6	10,312±1781	47.4±11.4	148.33±18.1	48.8±5.9
	*Lauerwald et al.7	3,188±575	24.6±2.9	15.1±4.9	4.9±1.6
	†This study	4,369±393	21.8±11.5	19.6±4.0	6.2±1.6
Indonesia	Raymond et al.6	6,009±4554	59.9±11.3	75.4±30.5	144.7±54.5
	*Lauerwald et al.7	3,188±575	24.6±2.9	17.3±5.6	33.1±10.7
	†This study	5,535±498	21.9±4.71	26.6±4.6	53.8±12.4
SE-Asia	Raymond et al.6	5,552±3943	63.4±19.6	68.4±24.4	181.5±64.8
	*Lauerwald et al.7	3,188±575	24.6±2.9	14.4±5.4	44.6±14.4
	†This study	5,155±464	21.8±7.0	24.5±4.4	66.8±15.7

Studies include that of Raymond et al.6, Lauerwald et al.7 and this study. Errors indicate the s.e. (ref. 6), largest deviation from the mean (ref. 7) and best/worst case deviation (this study).

^*CO₂ yield and fluxes for Lauerwald et al.7 are estimated based on the river surface areas defined in our study (Table 2).

^†Errors for pCO₂ are based on the average s.e. of 9% as found for the studied rivers.