Publikationsdatum:
2024-06-13
Beschreibung:
To determine the effect of the rate of temperature increase (acute vs. gradual) and magnitude as well as the timing of nutrient addition on a natural marine phytoplankton community, a bottle incubation experiment has been conducted at the Institute for Chemistry and Biology of the Marine Environment (ICBM) in Wilhelmshaven, Germany. The community was collected at the Helgoland Roads long-term time series site in the German part of the North Sea (https://deims.org/1e96ef9b-0915-4661-849f-b3a72f5aa9b1) on the 6ᵗʰ of March 2022. The surface water containing the phytoplankton community was collected from the RV HEINCKE with a pipe covered with a 200 µm net attached to a diaphragm pump. In the first experimental run, the community was exposed to either gradual or acute temperature increase (from 6 to either 12 or 18°C) with 25 different N:P supply ratios added as a batch at the beginning of the bottle incubation. Simultaneously, the same community was gradually acclimated to their experimental temperatures under ambient nutrients and was used in a second experimental run in which it received the same 25 different N:P supply ratios after temperature acclimation. The light conditions were set to 175 µmol s-1 m-2 and a day-night cycle of 12h:12h which corresponds to the natural conditions at that time of the year. With this, it was possible to test the effect of a gradual vs. acute temperature increase and the timing of nutrient addition i.e., before or after the temperature change. This experimental set-up summed up to 400 units (8 temperature treatments x 5 nitrogen levels x 5 phosphorus levels x 2 replicates). Each experimental run was ended after 12 days. Fluorescence (395/680 Exc./Em.) was measured every second day using a SYNERGY H1 microplate reader (BioTek®) to determine phototrophic growth over time. At the end of each experiment, one replicate was filtered onto pre-combusted acid-washed glass microfiber filters (WHATMAN® GF/C) for intracellular carbon (POC), nitrogen (PON), and phosphorus (POP) content. The POP filters were pre-combusted and then analysed by molybdate reaction after digestion with a potassium peroxydisulfate solution (Wetzel and Likens 2003). The POC and PON filters were dried at 60°C before they were measured in an elemental analyser (Flash EA 1112, Thermo Scientific, Walthman, MA, USA).
Schlagwort(e):
Bottle number; Calculated, ratio of molar masses; Carbon, organic, particulate; Carbon, organic, particulate/Nitrogen, organic, particulate ratio; Carbon, organic, particulate/Phosphorus, organic, particulate ratio; Date/time start, experiment; Diaphragm pump; coupled with pipe [covered with a 200 µm net]; Elemental analyzer (EA), Thermo Scientific, FlashEA 1112; Event label; Experimental run; growth; Growth rate, linear; HE593; HE593_SOT22; Heincke; Measured according to Wetzel and Likens (2000); N:P ratio; Nitrogen; Nitrogen, organic, particulate; Nitrogen, organic, particulate/Phosphorus, organic, particulate ratio; Nitrogen, total, dissolved/Phosphorus, total, dissolved ratio; Nitrogen, total dissolved; North Sea; nutrient limitation; nutrients; Phosphorus; Phosphorus, organic, particulate; Phosphorus, total dissolved; Phytoplankton; Replicates; SOT22; stoichiometry; Temperature; Temperature, water; Temperature change; temperature stress; Treatment: nitrogen; Treatment: Nitrogen/Phosphorus ratio; Treatment: phosphorus; Treatment: temperature description; Type of study
Materialart:
Dataset
Format:
text/tab-separated-values, 6800 data points
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