CTD, water quality, plankton species abundance, quantitative phytoplankton profiles and chlorophyll a and b concentrations in sediment samples data collected from R/V Bellows cruise BE-1212 in the northern Gulf of Mexico from 2011-05-21 to 2013-09-16 (NCEI Accession 0175053)

This dataset contains CTD, water quality, plankton species abundance, quantitative phytoplankton profiles, and chlorophyll a and b concentrations in sediment samples data collected from R/V Bellows cruise BE-1212 in the northern Gulf of Mexico from 2011-05-21 to 2013-09-16. CTD data were collected from 26 sites from 2012-05-05 to 2012-05-07. In addition, water samples were collected and analyzed for nutrient concentrations at the Wetlands Research Laboratory at the University of West Florida. Quantitative nanoplankton census data were taken via scanning electron microscopy (SEM) to determine after-the-fact, the effects of the Macondo Oil Spill on skeletal (coccolith)-bearing phytoplankton. Plankton samples were collected from 14 offshore shelf sites from 2012-05-05 to 2012-05-07 and abundances were recorded as counts and as percentages of the total sample. Quantitative phytoplankton profiles were taken specifically at station P7, and these data includes the depth, the volume filtered, the number of cells of each taxon counted, the calculated abundance of each taxon in cells per liter, and micrographs taken during the analysis. For this, one-liter samples were collected from the surface and at different depths using Niskin bottles. Samples were filtered onto a 0.45 micrometer nitrocellulose filter and air-dried. A portion of each filter was mounted on an aluminum stub, sputter-coated, and examined with a JEOL JSM-6480 LV scanning electron microscope. Diatoms, coccolithophores, and armored dinoflagellates were identified to the lowest possible taxonomic category. The number of cells of each taxon in a field of view at a magnification of 1000x was recorded, with up to 700 fields-of-view examined, depending on the density of phytoplankton in the sample. Similarly, sediment samples were collected using replicate Shipek sediment grabs from 28 samples sites between 2011-05-21 and 2013-09-16. Sediment was frozen in the field for transfer to the laboratory. Once in the laboratory, samples were acetone extracted and fluorescence was determined on a Perkin Elmer scanning fluorometer. Standard chlorophyll preparations were used for sample quantification.