Title:
UPTAKE KINETICS AND STORAGE CAPACITY OF DISSOLVED INORGANIC PHOSPHORUS AND CORRESPONDING DISSOLVED INORGANIC NITRATE UPTAKE IN SACCHARINA LATISSIMA AND LAMINARIA DIGITATA (PHAEOPHYCEAE)

Authors:
Alexander Lubsch1, 2 and Klaas R. Timmermans1
(alexander.lubsch(at)nioz.nl and klaas.timmermans(at)nioz.nl)
1 NIOZ Royal Netherlands Institute for Sea Research, Department of Estuarine and Delta Systems, and Utrecht University, PO Box 140, 4401 NT Yerseke, the Netherlands
2 Department Ocean Ecosystems, University of Groningen, PO Box 72, 9700 AB Groningen, the Netherlands

Year:
2018-2019

Research objective:
Quantification of uptake kinetics and uptake management strategies in the seaweeds S. latissima and L. digitata.

Dataset content:
The included data is the untreated raw data and attributes to the surface area (SA), as a measure for growth and for standardization of dissolved inorganic phosphorus (DIP) and dissolved inorganic nitrogen (DIN) uptake rates, analysis of DIP and DIN of the seawater medium to refer to uptake by the seaweeds, and fluorescence measurements (Fv/Fm) of sporophytes under DIP depletion/limitation/repletion conditions to refer to induced nutritional stress.

Method:
In a 'pulse-and-chase assay (daily refreshment (“pulse”) of seawater and daily nutrient analysis of seawater (“chase”), daily uptake rates of Saccharina latissima and Laminaria digitata exposed to a range of DIP concentration (0.0 - 0.2 - 0.4 - 0.8 - 1.5 - 3.0 - 6.0 µmol·L-1) and a DIN concentration of 50 µmol·L-1 were measured over 21 days. Growth was followed by non-destructive method of surface area (SA) analysis on a weekly basis for 3, respectively 5 weeks. In a second 'pulse-and-chase' assay, Fv/Fm was followed any other day in Laminaria digitata for 44 days and in Saccharina latissima for 68 days. Sporophytes were cultivated in DIP and DIN additions of 3 µmol·L-1 and 50 µmol·L-1 (+/+), DIP and DIN depletion (-/-), or a limitation of either DIP or DIN (+/-), (-/+).

Abbreviations:
DIN – Dissolved inorganic nitrogen
DIP – Dissolved inorganic phosphorus
Fv/Fm - Fv refers to variable fluorescence; Fm refers to maximum fluorescence 
SA – Surface area (cm2)