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 September 18, 2015 to September 12, 2016.
Suggested Citation:
Uta Passow. 2017. Sediment Trap (raw data) - Mississippi Canyon, Gulf of Mexico, 1540m, September 18, 2015 - September 12, 2016. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/N71C1V8T
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; Details; Latitude (Lat, decimal degrees); Longitude (Long, decimal degrees); Depth (m); Comments; Cup; Start date time (MM/DD/YYYY HH:MM); End date time (MM/DD/YYYY HH:MM); Trap type; Trap area (m^2); Collection time (d); Date filtered (DD-MM-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); 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; Comments
Methods:
Detailed methods for trap deployment, sample processing and analytical methods are described by Giering, S.L.C., Sanders, R., Martin, A.P., Henson, S.A., Riley, J.S., Marsay, C.M., & Johns, D.G. (2017). Particle flux in the oceans: Challenging the steady state assumption. Global Biogeochemical Cycles, 31(1): 159-171 doi: 10.1002/2016GB005424. 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