Particles and Zooplankton Amino Acid Compound Specific Isotope Analyses (AA-CSIA) and zooplankton biomass at Station ALOHA and the Equatorial Pacific from R/V Kilo Moana cruises KM1407, KM1418, & KM1515 from 2014-2015 (NCEI Accession 0278562)

This dataset contains biological, chemical, and physical data collected on R/V Kilo Moana during cruises KM1407, KM1418, and KM1515 in the North Pacific Ocean from 2014-02-19 to 2015-09-08. These data include Carbon, biomass, d15N measured in biota, depth, and particulate organic Carbon (POC). The instruments used to collect these data include Isotope-ratio Mass Spectrometer, MOCNESS, McLane Pump, and Multiple Unit Large Volume Filtration System. These data were collected by Brian N. Popp and Jeffrey C. Drazen of University of Hawaii at Manoa as part of the "Collaborative Research: Isotopic insights to mercury in marine food webs and how it varies with ocean biogeochemistry (Hg_Biogeochemistry)" and "Evaluating the relative importance of suspended and sinking particles to the meso and bathypelagic food web in the central North Pacific (SuspendSinkPart)" projects. The Biological and Chemical Oceanography Data Management Office (BCO-DMO) submitted these data to NCEI on 2020-03-31.

The following is the text of the dataset description provided by BCO-DMO:

Particles and Zooplankton Amino Acid Compound Specific Isotope Analyses (AA-CSIA) and zooplankton biomass in the Equatorial North Pacific and station Aloha

Dataset Description:
Acquisition Description:
Particles were collected using in situ McLane pumps equipped with mini-MULVFS (Bishop et al. 2012) 2-tiered filter holders. Particle collection captured sequentially large (>53 µm) particulates on acid-cleaned Nitex mesh filters and small particles (<53 µm) on pre-combusted GFF or QMA filters at discrete depths for amino acid compound-specific isotope analysis (AA CSIA) and for particulate carbon and nitrogen. This method is designed to exclude motile metazoans but include all other ambient, non-swimming particulate matter (see Bishop et al. 2012). Immediately after collection, large particles were rinsed off of the Nitex screens and onto pre-combusted 25-mm QMA filters using 0.2 µm filtered seawater. All filters were frozen at -20°C or -80°C as soon as possible after collection.

Zooplankton were collected using a 1-m² MOCNESS net during the day (~09:00-15:00) and at night (~20:00-03:00). Night and day tows were repeated to obtain replicate samples for biomass and isotopic analyses. Upon collection, each sample was size-fractionated using 0.2, 0.5, 1.0, 2.0 and 5.0 mm mesh sieves, filtered onto pre-weighed 47 mm filters of 0.2 mm Nitex mesh and stored frozen at -80ºC.

For nitrogen isotope composition of the amino acids, particles and zooplankton samples were freeze dried and analyzed following the methods Hannides et al. (2013). δ¹⁵N values of source amino acids ( δ¹⁵NSrc₋AA ) for both particles and zooplankton were calculated as the average δ¹⁵N of: serine, phenylalanine, lysine and glycine. Freeze-dried zooplankton filters for all size fractions were weighed to calculate zooplankton biomass (mg in dry weight/m³) at each depth during the day and at nighttime.