Hydrochemistry measured on water bottle samples during METEOR cruise M10/1

• Main Authors: Passow, Uta, Peinert, Rolf
• Format: Dataset
• Language: English
• Published: PANGAEA 1993
• Subjects: Ammonium; Bottle; Niskin 30-L; Carbon; organic; particulate; Carbon/nitrogen analyser (GF/F filtered); Chlorophyll a; fluorometric determination (Grasshoff et al.; 1983; Chemie GmbH); Colorometric analysis; manual; Continuous Flow Automated Analysis (Gordon et al.; 1993; WOCE Tech Rpt 93-1); Date/Time of event; DEPTH; water; Elevation of event; Event label; Gravimetric analysis (GF/F filtered); JGOFS; Joint Global Ocean Flux Study; Latitude of event; Longitude of event; M10/1; M10/1-RO6-241_003; M10/1-RO6-241_004; M10/1-RO6-245_006; M10/1-RO6-245_007; M10/1-RO6-249_009; M10/1-RO6-249_010; M10/1-RO6-254_011; M10/1-RO6-254_012; M10/1-RO6-260_013; M10/1-RO6-260_014; M10/1-RO6-266_016; M10/1-RO6-266_017; M10/1-RO6-273_020; M10/1-RO6-273_021; M10/1-RO6-279_024; M10/1-RO6-279_025; M10/1-RO6-283_028; M10/1-RO6-283_029; M10/1-RO6-287_031; M10/1-RO6-287_032; M10/1-RO6-292_034; M10/1-RO6-292_035; North Atlantic; Northeast Atlantic
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.65476; https://doi.org/10.1594/PANGAEA.65476

The relationship between the vertical flux of microplankton and its standing stock in the upper ocean was determined in the subtropical (33°N, 21°W) and tropical (18°N, 30°W) northeast Atlantic in spring 1989 as part of the North Atlantic Bloom Experiment. In the subtropical area specific sedimentation rates at all depths were low (0.1% of standing stock) and 10-20% of settled particulate organic carbon (POC) was viable diatoms. The high contribution of viable diatoms, their empty frustules and tintinnid loricae to settled material characterized a system in transition between a diatom bloom sedimentation event and an oligotrophic summer situation. In the tropical area specific sedimentation rates were similar, but absolute rates (3 mg C m?2 day?1) were only about a third of those in the subtropical area. Microplankton carbon contributed only 2-6% to POC. Hard parts of heterotrophs found embedded in amorphous detrital matter suggest that particles had passed through a complex food web prior to sedimentation. Coccolithophorids, not diatoms dominated the autotrophic fraction in traps, and a shift in the composition of autotrophs may indicate a perturbation of the oligotrophic system.