Cruise inventory
RRS Discovery D284 (AMT15)
Cruise summary report
| Cruise Info. | |||||||||
| Cruise period | 2004-09-17 — 2004-10-29 | ||||||||
| Status | Completed | ||||||||
| Port of departure | Southampton, United Kingdom | ||||||||
| Port of return | Cape Town, South Africa | ||||||||
| Purpose | Research | ||||||||
| Objectives | The Atlantic Meridional Transect (AMT) is a UK Natural Environmental Research Council (NERC) funded project which aims to quantify the nature and causes of ecological and biogeochemical variability in the planktonic ecosystems of the Atlantic Ocean, and the effects of this variability on the biological carbon pump and on air-sea exchange of radiatively active (greenhouse) gases and aerosols. The programme continues a series of 12 bi-annual transect cruises between the UK (50degN and the Falkland Islands (52degS) which took place between 1995 and 2000 making measurements of hydrographic and bio-optical properties, plankton community structure and primary production.
This cruise AMT 15 ? DI284 between Southampton and Cape Town, South Africa, is the fourth of a further six cruises taking place between 2003 and 2005. This project allows 45 investigators from 6 partner UK institutions to work in collaboration with European and American colleagues to test nine inter-related scientific hypotheses which fall within the following objectives: a) to determine how the structure, functional properties and trophic status of the major planktonic ecosystems vary in space and time; b) to determine the role of physical processes in controlling the rates of nutrient supply, including dissolved organic matter, to the planktonic ecosystem; c) to determine the role of atmosphere-ocean exchange and phot-degradation in the formation and fate of organic matter. DI284 has UK scientists onboard from Plymouth Marine Laboratory, Southampton Oceanography Centre and the universities of Plymouth, East Anglia, Strathclyde and Warwick, and is hosting colleagues from Vigo and Barcelonna in Spain, Napoli in Italy and the Bigelow Laboratory for Ocean Sciences, USA. | ||||||||
| Chief scientist | Andy Rees (Plymouth Marine Laboratory) | ||||||||
| Project | Atlantic Meridional Transect (AMT) | ||||||||
| Cruise report |  (2.03 MB) | ||||||||
| Ocean/sea areas | |||||||||
| General | North East Atlantic Ocean (limit 40W) South Atlantic Ocean | ||||||||
| Specific | Eastern Atlantic Ocean | ||||||||
| Track charts |  | ||||||||
| Measurements | |||||||||
| Physical oceanography | |||||||||
| Transparency (eg transmissometer) | Quantity: activity duration in days = 41 Description: Semicontinuous measurements of downwelling irradiance, upwelling radiance (40o from nadir, 120o azimuth from sun) and sky radiance (40o from zenith, 120o azimuth from sun) | ||||||||
| Optics (eg underwater light levels) | Quantity: number of profiles = 30 Description: Measurements of spectral attenuation and absorption at 412, 440, 488, 510, 532, 555, 650, 676 and 715nm. With concurrent CTD data for correction. | ||||||||
| Optics (eg underwater light levels) | Quantity: number of profiles = 30 Description: Measurements of the volume scattering function at 100, 125 and 150 degrees. | ||||||||
| Optics (eg underwater light levels) | Quantity: number of profiles = 30 Description: Measurements of downwelling irradiance and upwelling radiance at 412, 443, 490, 510, 555, 670 and 765nm. | ||||||||
| Optics (eg underwater light levels) | Quantity: activity duration in days = 41 Description: Semicontinuous measurements of chlorophyll fluorescence, optical backscattering, absorption/attenuation (9 wavelengths) taken from ships nontoxic line | ||||||||
| Optics (eg underwater light levels) | Quantity: number of measurements = 25 Description: Hyperspectral measurements of downwelling irradiance and upwelling radiance at the sea surface. | ||||||||
| Chemical oceanography | |||||||||
| Oxygen | Quantity: number of samples = 303 Description: Water for winkler dissolved oxygen concentration for calibration of the CTDs SBE oxygen sensors. | ||||||||
| Other dissolved gases | Quantity: activity duration in hours = 30 Description: Surface N2O/CH4 underway measurements | ||||||||
| Phosphate | Quantity: number of samples = 1750 Description: Water samples analysed from the predawn CTD cast and midmorning all depths. All samples analysed for micromolar nitrate + nitrite, nitrite, silicate, phosphate. Micromolar ammonium only analysed for first five CTDs. Nanomolar nitrate + nitrite, nitrite and phosphate analysed for CTDs 3-18, 21-30, 44-98. | ||||||||
| Nitrate | Quantity: number of samples = 1750 Description: Water samples analysed from the predawn CTD cast and midmorning all depths. All samples analysed for micromolar nitrate + nitrite, nitrite, silicate, phosphate. Micromolar ammonium only analysed for first five CTDs. Nanomolar nitrate + nitrite, nitrite and phosphate analysed for CTDs 3-18, 21-30, 44-98. | ||||||||
| Nitrite | Quantity: number of samples = 1750 Description: Water samples analysed from the predawn CTD cast and midmorning all depths. All samples analysed for micromolar nitrate + nitrite, nitrite, silicate, phosphate. Micromolar ammonium only analysed for first five CTDs. Nanomolar nitrate + nitrite, nitrite and phosphate analysed for CTDs 3-18, 21-30, 44-98. | ||||||||
| Ammonia | Quantity: number of samples = 1750 Description: Water samples analysed from the predawn CTD cast and midmorning all depths. All samples analysed for micromolar nitrate + nitrite, nitrite, silicate, phosphate. Micromolar ammonium only analysed for first five CTDs. Nanomolar nitrate + nitrite, nitrite and phosphate analysed for CTDs 3-18, 21-30, 44-98. | ||||||||
| Silicate | Quantity: number of samples = 1750 Description: Water samples analysed from the predawn CTD cast and midmorning all depths. All samples analysed for micromolar nitrate + nitrite, nitrite, silicate, phosphate. Micromolar ammonium only analysed for first five CTDs. Nanomolar nitrate + nitrite, nitrite and phosphate analysed for CTDs 3-18, 21-30, 44-98. | ||||||||
| Trace elements | Quantity: number of stations = 34 Description: Determination of dissolved iron species (Fe(II) (<0.2 um) and total dissolved iron (<0.2 um and <0.02 um) Samples from 5 depths per daily station and daily surface underway samples. | ||||||||
| Radioactivity | Quantity: number of samples = 192 Description: Calcite production measurements based on radio-isotope (14C) phytoplankton labelling experiments (24hrs) using on-deck incubators. Both organic and inorganic production measured at three depths. | ||||||||
| Radioactivity | Quantity: number of samples = 672 Description: Primary production measurements based on radio-isotope (14C) phytoplankton labelling experiments (dawn to dusk) using on-deck incubators. Includes size-fractionation at two depths | ||||||||
| Radioactivity | Quantity: number of samples = 216 Description: Primary production measurements based on radio-isotope (14C) phytoplankton labelling experiments: Photosynthesis vs Irradiance (PvE) incubations. | ||||||||
| Isotopes | Quantity: number of samples = 578 Description: 15N Gaseous enrichment water samples. These were filtered and the filters retained Mass spec analysis at a later date. | ||||||||
| Isotopes | Quantity: number of samples = 144 Description: Nitrogenase activity measurements by the acetylene reduction assay, using G.C measurements. | ||||||||
| Other chemical oceanographic measurements | Quantity: number of samples = 74 Description: Water samples colected for DIC analysis by Dr Paul Quay, University of Washington, USA. | ||||||||
| Biology and fisheries | |||||||||
| Primary productivity | Quantity: number of samples = 192 Description: Calcite production measurements based on radio-isotope (14C) phytoplankton labelling experiments (24hrs) using on-deck incubators. Both organic and inorganic production measured at three depths. | ||||||||
| Primary productivity | Quantity: number of samples = 1800 Description: Water samples for gross primary production, community respiration and net community production rate measurements after 24 h deck incubations. | ||||||||
| Primary productivity | Quantity: number of samples = 672 Description: Primary production measurements based on radio-isotope (14C) phytoplankton labelling experiments (dawn to dusk) using on-deck incubators. Includes size-fractionation at two depths | ||||||||
| Primary productivity | Quantity: number of samples = 216 Description: Primary production measurements based on radio-isotope (14C) phytoplankton labelling experiments: Photosynthesis vs Irradiance (PvE) incubations. | ||||||||
| Phytoplankton pigs (eg chlorophyll, fluorescence) | Quantity: number of samples = 250 Description: Particle Absorbance samples at 6 euphotic light depths from the 3am optics cast. Samples stored frozen at -80. | ||||||||
| Phytoplankton pigs (eg chlorophyll, fluorescence) | Quantity: number of samples = 180 Description: HPLC samples from 6 light depths filtered from the 11am optics cast. Samples stored frozen at -80. | ||||||||
| Phytoplankton pigs (eg chlorophyll, fluorescence) | Quantity: number of samples = 400 Description: Size-fractionated (0.2, 2, 5 and 10 um) chlorophyll-a samples at 5 euphotic light depths (97%, 55%, 33%, 14%, 1% & 0.1%) from both the 3am and 11am CTD casts. Pigment extracted in 90% acetone | ||||||||
| Phytoplankton pigs (eg chlorophyll, fluorescence) | Quantity: number of samples = 100 Description: Particle Absorbance samples at 3 euphotic light depths from the 11am optics cast. Samples stored frozen at -80. | ||||||||
| Phytoplankton pigs (eg chlorophyll, fluorescence) | Quantity: number of samples = 180 Description: Chlorophyll A (acetone extract) filtered from 6 light depths from the 11am optics cast. Samples analysed on board. | ||||||||
| Phytoplankton pigs (eg chlorophyll, fluorescence) | Quantity: number of samples = 82 Description: Size fractionated (>5 um and total) chlorophyll-a samples from the grazing experiments in 15 stations. Pigment extracted in 90% acetone. | ||||||||
| Phytoplankton pigs (eg chlorophyll, fluorescence) | Quantity: number of samples = 295 Description: Chlorophyll-a samples at 5 euphotic light depths (97%, 55%, 33%, 14%, 1% & 0.1%) from both the 3am and 11am CTD casts. Pigment extracted in 90% acetone | ||||||||
| Phytoplankton pigs (eg chlorophyll, fluorescence) | Quantity: number of samples = 295 Description: Duplicate HPLC samples at 5 or 6 euphotic light depths (97%, 55%, 33%, 14%, 1% & 0.1%) from the 4am, single samples from the 11am optics cast. Samples stored frozen at -80 | ||||||||
| Phytoplankton pigs (eg chlorophyll, fluorescence) | Quantity: number of samples = 198 Description: Water for discrete lab based FRRF measurements for phytoplankton physiological parameters. Samples and filtered seawater blanks measured from pre-dawn cast at six depths. | ||||||||
| Phytoplankton pigs (eg chlorophyll, fluorescence) | Quantity: number of profiles = 25 Description: Measurements from Chelsea Instruments FRRF fluorometer from optics cast. | ||||||||
| Particulate organic matter (inc POC, PON) | Quantity: number of samples = 180 Description: POC samples from 6 light depths filtered from the 11am optics cast. Samples stored frozen at -80. | ||||||||
| Particulate organic matter (inc POC, PON) | Quantity: number of samples = 295 Description: POC/N samples at 5 or 6 euphotic light depths (97%, 55%, 33%, 14%, 1% & 0.1%) from both the 4am and 11am optics cast. Samples stored at -20 deg C | ||||||||
| Dissolved organic matter (inc DOC) | Quantity: number of stations = 35 Description: Samples from 12 depths for CDOM spectra and photreactivities | ||||||||
| Dissolved organic matter (inc DOC) | Quantity: number of samples = 250 Description: Water for duplicate DOC/N/P samples from all predawn CTD casts, preserved with phosphoric acid or frozen. | ||||||||
| Phytoplankton | Quantity: number of hauls = 34 Description: Phytoplankton and zooplankton for biomass and community description were fixed in buffered formaldehyde 4%. Samples collected from 200 to 0 m with a 63 um mesh net on 37 stations. | ||||||||
| Phytoplankton | Quantity: number of samples Description: Filter samples taken for particulate calcium (calcite) at 6-8 depths from euphotic zone (97%, 55%, 33%, 14%, 1% & 0.1%), 200 and 300m from 4am casts and only the euphotic depths from the 11am optics cast. Samples stored at -20 deg C | ||||||||
| Phytoplankton | Quantity: sample litres = 80 Description: Seawater collected from the DCM by CTD at 15 stations. Water was used to feed the zooplankton during 24 hour grazing experiments. | ||||||||
| Phytoplankton | Quantity: number of samples = 90 Description: Water for zooplankton for counting animals and determining biomass were fixed in buffered formaldehyde 4%. Samples from the experimental bottles (grazing experiments). | ||||||||
| Phytoplankton | Quantity: number of samples = 90 Description: Determine carbon and nitrogen content of zooplankton. Samples from the experimental bottles (grazing experiments). | ||||||||
| Phytoplankton | Quantity: sample litres = 20 Description: Seawater collected from the chlorophyll maximum by one Niskin bottle from each predawn CTD casts. Water was used to feed the sorted specimens during their incubation for reproduction experiments. | ||||||||
| Phytoplankton | Quantity: number of samples = 307 Description: Samples were collected from 8-11 depths from 34 stations via CTD for DNA isolation and subsequent dot blot hybridisation for phylogenetic analysis of phytoplankton, esp. Synechococcus. | ||||||||
| Phytoplankton | Quantity: number of samples = 307 Description: Samples were collected from 8-11 depths from 34 stations via CTD for fluorescence in situ hybridisation (FISH) for phylogenetic analysis of phytoplankton, esp. Synechococcus. | ||||||||
| Phytoplankton | Quantity: number of hauls = 35 Description: Phytoplankton and zooplankton for biomass and community description were fixed in buffered formaldehyde 4%. Samples collected from 200 to 0 m with a 200 um mesh net on 37 stations. | ||||||||
| Phytoplankton | Quantity: number of hauls Description: Phytoplankton and zooplankton for the grazing experiments collected from DCM to 0 m vertical plankton tows made with a 63 um and 200 um mesh net at 15 stations. | ||||||||
| Phytoplankton | Quantity: number of samples = 16 Description: Seawater. 100l samples from 2 depths from 8 stations were collected for cell concentration via tangential flow filtration for later cell sorting and fosmid library construction. | ||||||||
| Phytoplankton | Quantity: number of samples = 147 Description: Seawater. 10ml samples were taken from 4 depths from 34 stations for culturing and isolation of new Synechococcus strains. | ||||||||
| Phytoplankton | Quantity: number of samples = 100 Description: Water samples preserved in Lugol's solution and buffered formalin for the later enumeration of phytoplankton by microscopy | ||||||||
| Phytoplankton | Quantity: number of samples = 198 Description: Water for discrete lab based FRRF measurements for phytoplankton physiological parameters. Samples and filtered seawater blanks measured from pre-dawn cast at six depths. | ||||||||
| Phytoplankton | Quantity: number of samples = 250 Description: Filter samples taken for coccolithophore counts by scanning electron microscopy at a later date. Samples taken from five depths. | ||||||||
| Phytoplankton | Quantity: number of samples Description: Filter samples taken for biogenic silica at 6-8 depths from euphotic zone (97%, 55%, 33%, 14%, 1% & 0.1%), 200 and 300m from 4am casts and only the euphotic depths from the 11am optics cast. Samples stored at -20 deg C | ||||||||
| Phytoplankton | Quantity: number of samples Description: Filter samples on 0.4um HA filters for enumeration of coccolithopores and detached coccoliths, taken from 6-8 depths from euphotic zone (97%, 55%, 33%, 14%, 1% & 0.1%), 200 and 300m from 4am casts only | ||||||||
| Zooplankton | Quantity: number of hauls = 34 Description: Phytoplankton and zooplankton for biomass and community description were fixed in buffered formaldehyde 4%. Samples collected from 200 to 0 m with a 63 um mesh net on 37 stations. | ||||||||
| Zooplankton | Quantity: number of profiles = 84 Description: Microzooplankton abundance estimates from analyses of fixed samples (Lugol?s iodine 2%) from the CTD casts from 7 depth on 12 stations. | ||||||||
| Zooplankton | Quantity: number of hauls = 35 Description: Zooplankton samples for taxonomical description of the epipelagic community (0-200m). Fixed in buffered formaldehyde-seawater solution 4%. Collected using a WP-2 net (200 um mesh size) with filtering cod-end. Vertical hauls at 0.3 m.s-1 | ||||||||
| Zooplankton | Quantity: sample litres = 80 Description: Seawater collected from the DCM by CTD at 15 stations. Water was used to feed the zooplankton during 24 hour grazing experiments. | ||||||||
| Zooplankton | Quantity: number of profiles = 168 Description: Epifluorescence staining of filters (0.8 um and 2.0 um) from filtration of seawater samples collected via CTD at 7 depths from 12 stations for flagellate microscopic slide preparation. | ||||||||
| Zooplankton | Quantity: number of samples = 264 Description: Epifluorescence staining of filters (0.8 ?m and 2.0 ?m) from filtration of seawater samples collected at 12 stations from the grazing experiments for flagellate microscopic slide preparation. | ||||||||
| Zooplankton | Quantity: number of samples = 132 Description: Water for microzooplankton abundance estimates from analyses of fixed samples (Lugol?s iodine 2%) from the grazing experiments on 12 stations. | ||||||||
| Zooplankton | Quantity: number of samples = 90 Description: Water for zooplankton for counting animals and determining biomass were fixed in buffered formaldehyde 4%. Samples from the experimental bottles (grazing experiments). | ||||||||
| Zooplankton | Quantity: number of samples = 90 Description: Determine carbon and nitrogen content of zooplankton. Samples from the experimental bottles (grazing experiments). | ||||||||
| Zooplankton | Quantity: number of samples = 220 Description: Water collected via CTD at 6/7 depths from 33 stations were fixed in Lugol?s iodine for microzooplankton sizing and counting. | ||||||||
| Zooplankton | Quantity: sample litres = 20 Description: Seawater collected from the chlorophyll maximum by one Niskin bottle from each predawn CTD casts. Water was used to feed the sorted specimens during their incubation for reproduction experiments. | ||||||||
| Zooplankton | Quantity: number of hauls Description: 16 alive zooplankton samples were collected using a WP-2 net (200 um mesh size) equipped with a non filtering cod-end. Vertical hauls at 0.1 m.s-1. | ||||||||
| Zooplankton | Quantity: number of hauls = 35 Description: Phytoplankton and zooplankton for biomass and community description were fixed in buffered formaldehyde 4%. Samples collected from 200 to 0 m with a 200 um mesh net on 37 stations. | ||||||||
| Zooplankton | Quantity: number of hauls Description: Phytoplankton and zooplankton for the grazing experiments collected from DCM to 0 m vertical plankton tows made with a 63 um and 200 um mesh net at 15 stations. | ||||||||
| Pelagic bacteria/micro-organisms | Quantity: number of profiles = 84 Description: Picoplankton abundance estimates from analyses of fixed samples (paraformaldehyde 1%) from the CTD casts by flow cytometry from 7 depth on 12 stations. | ||||||||
| Pelagic bacteria/micro-organisms | Quantity: number of profiles = 70 Description: Samples collected from all depths to determine the abundance of picoplankton by flow cytometry. | ||||||||
| Pelagic bacteria/micro-organisms | Quantity: number of samples = 132 Description: Water for picoplankton abundance estimates from analyses of fixed samples (paraformaldehyde 1%) from the grazing experiments on 12 stations. | ||||||||
| Pelagic bacteria/micro-organisms | Quantity: number of samples = 141 Description: Cyanobacteria samples for DNA analysis of the relatedness of populations over geographical distance and depth from the predawn CTD casts. | ||||||||
| Pelagic bacteria/micro-organisms | Quantity: number of samples = 143 Description: Unfiltered water for viral (cyanophage) lysis experiments from the predawn CTD casts. | ||||||||
| Pelagic bacteria/micro-organisms | Quantity: number of stations = 29 Description: Heterotrophic bacterial production measurements from 6 depths using radiolabelled tracers | ||||||||
| Pelagic bacteria/micro-organisms | Quantity: number of stations = 12 Description: Estimation of grazing on bacteria using radiolabelled tracers | ||||||||
| Pelagic bacteria/micro-organisms | Quantity: number of stations = 15 Description: Samples from 1-2 depths collected and frozen for molecular analysis of bacterial community composition | ||||||||
| Other biological/fisheries measurement | Quantity: number of samples = 141 Description: Water for concentrated cyanophage samples for DNA analysis of the relatedness of populations over geographical distance and depth from the predawn CTD casts. | ||||||||
| Data held at BODC | |||||||||
| Series/Profiles | |||||||||
| 1 Transmissometer |
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| Discrete samples | |||||||||
| 32 Atmospheric air sampling pump | Inorganic phosphorus species concentrations in the atmosphere Sulphur species concentrations in the atmosphere Concentration of nitrogen species in the atmosphere Metal concentrations in the atmosphere Stable isotope enrichment in the atmosphere Concentration of inorganic halogens in the atmosphere | ||||||||
| 105 CTD frame plus rosette sampler | Particulate total and organic nitrogen concentrations in the water column Primary production in the water column Raw suspended particulate material optical sensor output Phytoplankton taxonomic abundance in water bodies Phosphate concentration parameters in the water column Light absorption in the water column Density of the water column Dissolved total or organic phosphorus concentration in the water column Visible waveband radiance and irradiance measurements in the water column Particulate total and organic carbon concentrations in the water column Transmittance and attenuance of the water column Concentration of silicon species in the water column Silicate concentration parameters in the water column Dissolved oxygen parameters in the water column Nitrate concentration parameters in the water column New production in water bodies Dissolved total and organic nitrogen concentrations in the water column Temperature of the water column Bacteria generic abundance in water bodies Carotenoid pigment concentrations in the water column Particulate inorganic carbon concentrations in the water column Salinity of the water column Raw light meter output Dissolved metal concentrations in the water column Nitrite concentration parameters in the water column Chlorophyll pigment concentrations in the water column Oxygen production and respiration in the water column | ||||||||
| 10 Rain water collector | Metadata parameters Precipitation chemistry | ||||||||
| 247 Sample taken from ship's non-toxic supply | Phosphate concentration parameters in the water column Particulate total and organic carbon concentrations in the water column Total metal concentrations in water bodies Total dissolved inorganic carbon (TCO2) concentration in the water column Concentration of silicon species in the water column Nitrate concentration parameters in the water column Particulate inorganic carbon concentrations in the water column Salinity of the water column Stable isotope enrichment in the water column Dissolved metal concentrations in the water column Nitrite concentration parameters in the water column Chlorophyll pigment concentrations in the water column |
