Dataset: Elemental composition of phytoplankton communities from multivariate mesocosm experiments conducted with a natural phytoplankton community from Narragansett Bay, RI.

The elemental composition of phytoplankton communities was analyzed via multivariate mesocosm experiments conducted with a natural phytoplankton community from Narragansett Bay, RI. Water was incubated in triplicate at -0.5ºC, 2.6ºC, and 6ºC for 10 days. At each temperature, treatments included both nutrient amendments (N, P, Si addition) and controls (no macronutrients added).

At the onset and conclusion of the incubation for all treatments, and additionally at each dilution time point for 2.6 and 6ºC amended treatments, each biological incubation replicate was assessed for particulate organic carbon (POC) and nitrogen (PON), and biogenic silica (BSi) content. POC and PON were evaluated in triplicate by harvesting cells onto 25 millimeter (mm) GF/F filters which had been pre-combusted at 450ºC for 24 hours.  Filters were then analyzed on a Costech Elemental Combustion System (Costech Analytical Technologies Inc.). BSi content was assessed by filtering cells in triplicate onto 2 micrometer (µm) polycarbonate filters and analyzing them on a Barnstead Turner SP-830 spectrophotometer, following the methods of Strickland and Parsons (1972). Additionally, nutrient analyses of ammonium, phosphate, silicate, and nitrite/nitrate (total inorganic nitrogen) were evaluated using a Lachat Quikchem 8500 analyzer (Hach) at the University of Rhode Island Marine Science Research Facility.

For complete methodology, see “The Interactive Effects of Temperature and Nutrients on a Spring Phytoplankton Community” (Anderson et al, in prep).

Note: Due to operator error, one replicate of POC and PON had to be discarded from the 6ºC amended incubation.