Primary, new and size fractionated production Elskens/Boyd and the Vertigolinians PP was assessed by 13 C and 14 C-bicarbonate incorporations NBP was assessed by 15 NH 4, 15 NO 3, 15 NO 2 & 15 N 2 enrichment and dilution experiments NP was estimated with the f ratio concept

Protocol 14 C* All incubations were conducted at 6 depths over one daylight period in a on-deck incubator with filters to simulate the light quantity and color at the appropriate depths. PP was integrated using the trapezoid rule in the upper 100m (ALOHA) and 50m (K2) Size fractionated PP was performed on >20, 5-20, 2-5 and 0.2-2µm. * JGOFS protocol

Protocol 13 C* and 15 N* Kinetic experiments were conducted on deck in a simulated in situ light and temperature controlled incubator at 4 depths. Gross NBP was determined using weighted least squares NBP was integrated using the trapezoid rule in the upper 100m (ALOHA) and 50m (K2) * JGOFS protocols

PP Hot- 14 C (0-100m) 461 ± 134 mg C m -2 d -1 (n=166) PP VERTIGO- 13 C (0-100m) 224 ± 26 mg C m -2 d -1 (n=8) PP VERTIGO- 14 C (0-100m) 198 ± 29 mg C m -2 d -1 (n=2) z- 13 C = (p=0.039) z- 14 C = (p=0.025 ) AOAC/IUAPAC rules |z| ≤ 2satisfactory 2 < |z| ≤ 3 questionable |z| > 3unsatisfactory Station ALOHA

Relationship between the 13 C and 14 C- bicarbonate incorporation rates during Vertigo

Depth-integrated primary productions at Sta. ALOHA and K2

Size fractionated 14 C primary production

Depth-integrated N based production at Sta. ALOHA and K2

Relative importance of nitrogenous substrates to phytoplankton nutrition

Nitrogen remineralisation rates: Compartmental model analysis Three compartment open model describing exchange reactions between ammonium (A), nitrate (N) and particulate nitrogen (P). where X i is the N concentration of isotope p within compartment i at time t, k ij is the rate constant for exchange from compartment i to compartment j (in reciprocal time units), p is the isotope 15 N or 14 N and n represents the number of compartments  The mass balance differential equations are solved numerically  Values for the rate constants are obtained with weighted least squares techniques

Ammonium net transformation rates at K2

Depth-integrated bacterial mineralisation and ammonium production at K2 BCD data from Ben Van Mooy NH4 production is calculated using an isotope dilution model and represents both the ammonification (bacteria) and excretion (zooplankton) rates. BNR is calculated using the BCD* data with a conversion factor of 3. It represents ammonification only

Build-up of ammonium stock at K2 Slope = 6 ± 1 mmol m -2 d -1

Decrease of PN stock at K2 Slope = -1.1 ± 0.2 mmol m -2 d -1

Differential mass balance equations at ALOHA dNH 4 /dt  0 = RNH 4 – RNO 2 – UNH 4 dNO 2 /dt  0 = RNO 2 – RNO 3 – UNO 2 dNO 3 /dt  0 = RNO 3 –UNO 3 dPN/dt  0 =  N –LPN Variables in black represent direct fiel measurements, while those in red are obtained with mass balance constrains

Tentative of N cycle for the photic zone at Sta. ALOHA and K2 395 ± ± 38 NH4 NO2 NO3 N2 RNP (0-50m) NNP (0-50m) 570 ± 180 DIN ExPN (150m)  ns orgN - 97 ALOHA K2 8 ± 3 44 ± 20 4 ± 1 11 ± 4 NO2 NH4 NO3 N2 RNP (0-100m) NNP (0-100m) 59 ± ± 4 11 ± 4 DINorgN ExPN (150m) 7 ± 2 Unit µmol m -2 h -1 ExPN data from Ken Buesseler

Tentative of C cycle for the photic zone at Sta. ALOHA RP: 199 ± 40 PP (0-100m) 224 ± 26 ExPOC (150m) 19 ± 4 NP: 25 ± 12 BCD (0-100m) 503 ± 61 BCD ( m) 47 ± 2 RP: 409 ± 82 PP (0-100m) 460 ± 134 ExPOC (150m) 19 ± 4 NP: 52 ± 24 BCD (0-100m) 503 ± 61 BCD ( m) 47 ± 2 with median VERTIGO PP with median HOT PP BCD data from Ben Van Mooy and ExPOC data from Ken Buesseler Unit mg C m -2 d -1

Tentative of C cycle for the photic zone at Sta. K2 RP: 404 ± 84 PP (0-50m) 523 ± 117 ExPOC (150m) 68 ± 2 NP: 119 ± 42 BCD (0-50m) 343 ± 18 BCD (50-150m) 9 ± 4 RP: 336 ± 34 PP (0-50m) 404 ± 28 ExPOC (150m) 23 ± 2 NP: 67 ± 23 BCD (0-50m) 328 ± 72 BCD (50-150m) 10 ± 5 Deployment 1 Deployment 2 Unit mg C m -2 d -1 BCD data from Ben Van Mooy and ExPOC data from Ken Buesseler