SBI Expected Datasets – Summer Cruise

 

Cruise: HLY-02-03

 

Hydrographic Measurements (Codispoti and Swift)

Measurements: CTD-Temperature, CTD-Salinity, CTD-Dissolved Oxygen, light transmission, fluorometric chlorophyll, fluorometric dissolved organic matter (cDOM; Haardt, fluorometer), and PAR (Photosynthetically Active Radiation). ADCP – Broad Band 150 kHz and Ocean Surveyor 75 kHz velocity profiles.

 

                           Bottle samples were analyzed for: salinity, dissolved oxygen, ammonium, nitrate, nitrite, phosphate, dissolved silicon, urea, chlorophyll and phaeophytin concentrations.

 

Carbon and Nitrogen Cycling in Seawater (Hansell and Bates)

Measurements: Total Alkalinity, DIC (Total CO2), Dissolved Organic Carbon, Total Dissolved Nitrogen, Particulate Organic Carbon, Particulate Nitrogen, Total Nitrogen

 

Primary Production, Bio-optics, & Remote Sensing of Ocean Color (Ruble and Cota)

Measurements: Phytoplankton pigment (HPLC) and cell count samples, surface optics (SO), sun photometry (Sun), passive optical (PO) profiles, and active optical (AO) profiles at daytime stations.

 

Microbiology (Kirchman)

Measurements: bacterial production (thymidine (DNA) and leucine (protein) incorporation) and samples for bacterial biomass (abundance and biovolume) and various molecular assays of bacterial community structure (“species” composition) in the upper 100 to 150 m.

                           In addition to the core bacterial measurements, including bacterial abundance and production, we are also measuring rates of community oxygen consumption and production in the water column.  Three depths in the photic zone and two below the 1% light depth are assayed for oxygen consumption in dark bottle incubations.  In addition, net oxygen production in photic zone samples are measured at simulated in situ irradiance in the flow through incubators on the foredeck in collaboration with the primary productivity group.

 

Biomarkers (Benner and Harvey)

Measurements: water samples collected for chemical characterization of dissolved organic matter (DOM), samples of dissolved and particulate matter, flash fluorometer. Together, these data will provide information on the concentrations and sources of DOM in the study region. Samples were also collected from the Kokolik River. In addition, particle and sediment samples were collected for organic biomarker analysis.

 

Radium Isotopes and XCTD Studies (Kadko)

Measurements: Depths sampled included a surface sample (~7m) from each station with 1-4 additional depths depending on location and total water depth. All samples were collected within 250m of the surface. Samples were analyzed for 224Ra and 228Th. At home samples were counted for 226Ra and 228Ra. XCTD measurements.

 

Microzooplankton Grazing, Growth, Biomass and Food for Mesozooplankton (Sherr)

Measurements: Microzooplankton Grazing Experiments (dilution assays), Microzooplankton growth rates, Microzooplankton biomass and analysis of phytoplankton community composition, Mesozooplankton grazing experiments, Protist DNA samples 

 

Mesozooplankton Process Studies (Campbell and Ashjian)

Measurements: grazing rates of the dominant copepod species/life stages on phytoplankton and microzooplankton, measures of carbon and nitrogen content, RNA/DNA (an indicator of metabolic activity), and, for actively reproducing species, egg production rates,   

 

Exchange of Plankton and Particles between the Shelf and Basin (Ashjian and

 Gallager)

Measurements: Video Plankton Recorder (VPR)

 

Water and Sediment Tracers, Sediment Metabolism and Benthic Community

 Structure (Grebmeier and Cooper)

Measurements: Water from both the productivity and service CTD casts were collected for O-18 measurements. A sub-sample of water from the chlorophyll max was collected and preserved in formalin for phytoplankton identification by Dr. Mickle Flint of the Shirshov Institute of Oceanology in Russia. Sediments were collected at each station using both a 0.1m2 van Veen grab and a 0.0133 m2 HAPS benthic corer. Sediment collections from both the van Veen and multiple-HAPS corer are analyzed for chlorophyll pigment content (both fluorometric and HPLC), total organic carbon and nitrogen content, grain size, and various radioisotopes. Sediment is sieved through 1 mm screens and retained animals preserved in 10% buffered formalin for analysis on land.

 

Carbon and Nitrogen Isotope Dynamics (Dunton)

Measurements: 239 POM water samples were collected for C13 and N15 mass spectrometry analysis (5 and 10 meter depths). 561 benthic invertebrate samples were collected for C13 and N15 analysis, including representative species of bivalves, amphipods, foraminifera, gastropods, polychaete worms, and echinoderms.  367 pelagic invertebrate samples were collected for C13 and N15 analysis, including representative species of chaetognaths, copepods, deep-sea shrimp, ctenophores, and amphipods.

 

Particle-reactive Radionuclides (Moran)

Measurements: Th-234, Pb-210,Ra-223, I-129, Cs-137, Ra-226/U-238 from sediments at different depths as well as benthic samples from the Cooper HAPS cores.

 

Zooplankton Distribution and Abundance (Smith)

Measurements: Four MOCNESS tows were attempted during the first half of this cruise.  Unfortunately, after the last two tows failed, it was clear the ice conditions and ship-handling capabilities were more than the MOCNESS could tolerate; consequently, MOCNESS towing was suspended. As a substitute for the MOCNESS, we towed Bongo nets vertically from three depths to the surface (1000m, 600m, 100m).  Fifty-two successful Bongo tows were completed.  After analyzing the species composition and abundance in each of these tows at a particular station, we will infer by difference which taxa were restricted to the deep layers.  The underway system worked continuously throughout the cruise so we have detailed surface maps of temperature, salinity, chlorophyll (calibration of this generously provided by D. Stockwell) and zooplankton.  We used underway samples to replace vertical one-meter net tows for nauplii while occupying stations.

Benthic Denitrification  (Devol and Christensen)

Measurements: The benthic denitrification group has make sediment flux and pore water measurement.  In total, we have sampled at 24 of the stations.  Core incubation experiments have been done for N2, O2 and nutrient fluxes as well as N:Ar ratio fluxes. Pore water profiles of O2, Total CO2 and nutrients have also been done, at all but one of the stations. Samples were also taken from the squeezed core for NO3 determination and frozen for later analysis.  An additional core was sampled by sectioning at most stations and pore waters were extracted for nutrient profiles (cm resolution). At many stations downcore samples were also taken for the determination of sulfate reduction rate by 35-SO4 tracer techniques.