Three levels of salinity (5, 20 and 35 psu) were fully
crossed with three levels of nutrients enrichment (NH4–
N concentration was 32 μmol l−1 in all treatments, while
three levels of PO4–P were tested: 6.4 μmol l−1; 2 μmol
l−1 and 0.8 μmol l−1). Seawater nutrient concentrations
were neglected, as they were relatively low (Table 1)
compared to added nutrient concentrations. The tested
salinity levels were obtained diluting the seawater with
demineralised water. In all experiments, the nutrient