Hyposalinity affects diurnal photoacclimation patterns in the rhodophyte Palmaria palmata under mimicked Arctic summer conditions: raw data from laboratory physiological measurements

The Arctic is one area that has been affected by rising temperatures, leading to an increase in meltwater in the water column. During the months of June/July 2019, fronds of the red seaweed Palmaria palmata in Kongsfjorden, Svalbard (78°55'56.0N 11°55'59.6E) were colected in the intertidal zone. For 21 days at 0ºC, P. palmata was subjected to variations of irradiance cycles and three different salinities SA 34 (control), 28 and 18 in laboratory conditions. Subsequently, measurements in triplicate (n=3) were made of photosynthetic parameters such as maximal quantum yield of PSII (Fv/Fm), non-photochemical quenching (NPQ), biochemical parameters such as quantification of pigments chlorophyll a (Chl a), lutein (Lut), zeaxanthin (Zeax), β-carotene (β-Car), and antioxidant activity 2,2-diphenyl-1-picrylhydrazyl (DPPH).