Table 1 Initial conditions, identified limiting nutrients, and responses to nutrient supply in experiments

Experiment	1	2	3	4	5	6	7	8	9	10	11
Date	2022/2/26	2022/3/1	2022/3/4	2022/3/7	2022/3/10	2022/3/14	2022/3/17	2022/3/24	2022/3/27	2022/3/30	2022/4/1
Longitude (°E)	−73.4	−82.7	−93.9	−103.4	−112	−125.3	−135.5	−152	−164	−174.9	179.3
Latitude (°S)	32.5	32.5	32.5	31.4	31.4	31.4	31.4	26.2	26.2	26.2	25.7
SST (°C)	19.5	19.9	22.1	23	24.8	25	24.2	26.8	26	26.7	26.2
Salinity (psu)	34.4	34.4	35.1	35.3	35.6	35.4	35.5	35.2	35.1	35	35
NOx (μM)	0.27	0.044	0.172*	0.066*	0.008	0.009*	0.009	0.005	0.005	0.005	0.006
PO₄³⁻ (μM)	0.47	0.275	0.173	0.177	0.118	0.069	0.087	0.014	0.006	0.001	0.001
DFe (nM)	0.17	0.35	0.19	0.18*	0.15	0.13	0.18	0.09	0.14	0.24	0.32
DMn (nM)	1.53	0.5	0.23	0.32	0.42	0.49	0.54	0.79	0.89	1.03	1.27
DAl (nM)	2.64	4.43	4.21	1.09	3.05	3.18	4.11	4.60	6.09	3.93	5.95
DZn (nM)	0.11	0.19	0.25	0.20	0.1	0.09	0.05	0.12	0.18	0.24	0.32
DCo (nM)	0.016	0.009	0.004	0.012	0.006	0.005	0.014	0.015	0.015	0.015	0.154
Chlorophyll-a (μg L⁻¹)	0.13	0.10	0.03	0.02	0.01	0.02	0.02	0.03	0.03	0.05	0.05
Fe_N* (nM)	0.05	0.33	0.11	0.15	0.15	0.13	0.18	0.09	0.14	0.24	0.32
P_N* (μM)	0.46	0.27	0.16	0.17	0.12	0.06	0.09	0.01	0	0	0
Limiting nutrients^‡	N(Fe)	N	N(Fe)	N(Fe)	N(Fe)	N(Fe, Zn)	N(Fe)	N(Fe)	N(P, Fe)	N(P)	N(P)

Fe_N* and P_N* are Fe and P concentrations in excess of assumed-average phytoplankton requirements relative to nitrate. NOx = NO₂ + NO₃.
Fe_N* = Fe - (NO₂ + NO₃) R_Fe:N.
P_N* = PO₄^3-- (NO₂ + NO₃) R_P:N.
Where R_Fe:N is the assumed-average Fe:N (0.469 × 10⁻³ mol:mol) stoichiometry in phytoplankton² and R_P:N is the assumed average P:N in phytoplankton (1/16).
*Nutrient determined at nearby underway sampling locations. ^‡As indicated by bulk chlorophyll-a changes. Elements in brackets indicates secondary limiting nutrients.

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