Abstract:
Raw data of a moored sediment trap deployed in the Northern Gulf of Mexico as part of a long-term time series to understand particle flux dynamics. Samples were collected from September 2014 to September 2015. The sediment trap collected at 1540 m, 120 m above the bottom.
Suggested Citation:
Uta Passow, Sarah Giering. 2017. Sediment Trap (raw data) - Mississippi Canyon, Gulf of Mexico, 1540m, 2014-09-22 - 2015-09-15. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/N78W3BQJ
Purpose:
Time series data of sedimentation rates in the Northern Gulf of Mexico. These are the raw analytical data for all cups of this deployment, covering roughly one year. Fluxes can be calculated from the available data. Other deployments from this time series are saved as separate files.
Data Parameters and Units:
Site, Latitude (decimal degrees), Longitude (decimal degrees), Depth (m), Comments, Cup, Date (MM/DD/YYYY HH:MM), Trap type, Trap area (m^2), Collection time (d). Date filtered (DD-MMM-YY), Filter number, Cup, Sample ID, Analysis type, Split fraction (the amount of the material that was analysed), Sediment height of trapped material (mm), Salinity of water in the cup (ppt), pH of water in the cup (pH), pH measurement Temp (degrees C), Phosphate of water in the cup (µM), Silicate of water in the cup (µM), Nitrate/nitrite of water in the cup (µM), Initial mass of filter; for split (g dry weight), Mass of filter after filtration; for split (g dry weight), Mass of filter after combustion; for split (g dry weight), Sample identification for analysis, Particulate inorganic + organic carbon (µg C/split), Particulate inorganic + organic nitrogen (µg N/split), Sample identification for analysis Particulate organic carbon (µg C/split), Particulate organic nitrogen (µg N/split), Biogenic silica (µmol Si/split), Transparent exopolymer particles (mg Gum Xanthan equivalent/split), Flag, and Comments.
Methods:
Detailed methods for trap deployment, sample processing and analytical methods are described by Giering et al. (2017). Supernatant water was analyzed as followed: Concentrations of NO3+NO2, PO4 and Si(OH)4 in the water overlaying the solid material were measured by simultaneous flow injection analysis (QuickCem 8000, Lachat Instruments). The pH (total scale) was measured with a spectrophotometer (Genesys 10SVIS) equipped with a single cell Peltier (SPG1A, both Thermo Scientific) using the indicator dye m-cresol purple (Sigma-Aldrich) at a constant temperature of 25ºC. The absorbance was measured at 730 nm, 578 nm, and 434 nm before and after dye addition (Clayton, 1993; Fangue, 2010). To calculate fluxes of a specific component x, use the formula: Flux=average(x/Split_fraction)/Deployment_time/Trap_Area.
Instruments:
Sediment trap: Parflux Mark78H-21, McLane Research Laboratories; Splitter: WSD-10, McLane; Flow injection analyzer: QuickCem 8000, Lachat Instrument; Spectrophotometer: Genesys 10SVIS, Thermo Scientific; Peltier: SPG1A, Thermo Scientific; CHN elemental analyzer: CEC44OHA, Exeter Analytical