Net ecosystem production and carbon dioxide fluxes in the Scheldt estuarine plume

BMC Ecology

Table 1 Average Scheldt river fresh water discharge (Q) from January and December of the previous year, flux of dissolved inorganic nitrogen (FDIN) from the Scheldt river, flux of total inorganic phosphorous (FP_tot) from the Scheldt river, winter-time DIN and PO₄^2- concentrations in the Belgian coastal zone and annual averages of the partial pressure of CO₂ (pCO₂), air-sea gradient of pCO₂ (ΔpCO₂), air-sea CO₂ flux (FCO₂) and net ecosystem production (NEP) at a fixed station in the Scheldt plume near the Zeebrugge harbor.

	Q (m³ s^-1)	FDIN (10⁶ mol d^-1)	FPtot (10⁶ mol d^-1)	DIN (μM)	PO₄^2- (μM)	pCO₂ (μatm)	ΔpCO₂ (μatm)	FCO₂ (mol m^-2 yr^-1)	NEP (mol m^-2 yr^-1)
2001	348	15	0.67	55.9	1.7	481	107	3.6	-4.2 ± 0.2
2002	302	12	0.41	45.2	1.3	480	97	3.2	-3.8 ± 0.2
2003	393	15	0.68	58.2	1.7	527	136	4.6	2.4 ± 0.1
2004	210	9	0.56	39.6	2.1	533	153	6.6	-5.7 ± 0.2

Fortnightly fresh water discharge data were provided by the Ministerie van de Vlaamse Gemeenschap Afdeling Waterbouwkundig Laboratorium en Hydrologisch Onderzoek. FDIN and FPtot were computed from average nutrient concentrations from January and December of the previous year from the Netherlands Institute of Ecology, Centre for Estuarine and Marine Ecology database and average Q from January and December of the previous year. Winter-time DIN and PO₄^2- concentrations were obtained from the Management Unit of the North Sea Mathematical Models monitoring data-base for December of the previous year at salinity 31. The error on the NEP estimates was evaluated by propagating an error on pCO₂ of ± 3 μatm on the DIC and air-sea CO₂ flux computations.

ISSN: 1472-6785