Fecal pellets flux at DYFAMED sediment traps

DOI

Because zooplankton feces represent a potentially important transport pathway of surface-derived organic carbon in the ocean, we must understand the patterns of fecal pellet abundance and carbon mobilization over a variety of spatial and temporal scales. To assess depth-specific water column variations of fecal pellets on a seasonal scale, vertical fluxes of zooplankton fecal pellets were quantified and their contribution to mass and particulate carbon were computed during 1990 at 200, 500, 1000, and 2000 m depths in the open northwestern Mediterranean Sea as part of the French-JGOFS DYFAMED Program. Depth-averaged daily fecal pellet flux was temporally variable, ranging from 3.04 * 104 pellets m2/d in May to a low of 6.98 * 102 pellets m2/d in September. The peak flux accounted for 50% of the integrated annual flux of fecal pellets and 62% of pellet carbon during only two months in mid-spring (April and May). Highest numerical fluxes were encountered at 1000 m, suggesting fecal pellet generation well below the euphotic zone. However, there was a trend toward lower pellet carbon with increasing depth, suggesting bacterial degradation or in situ repackaging as pellets sink through the water column. At 500 m, both the lowest pellet numerical abundance and carbon flux were evident during the spring peak. Combined with data indicating that numerical and carbon fluxes are dominated at 500 m by a distinct type of pellet found uniquely at this depth, these trends suggest the presence of an undescribed mid-water macro-zooplankton or micro-nekton community. Fecal pellet carbon flux was highest at 200 m and varied with depth independently of overall particulate carbon, which was greatest at 500 m. Morphologically distinct types of pellets dominated the numerical and carbon fluxes. Small elliptical and spherical pellets accounted for 88% of the numerical flux, while larger cylindrical pellets, although relatively rare (<10%), accounted for almost 40% of the overall pellet carbon flux. Cylindrical pellets dominated the pellet carbon flux at all depths except 500 m, where a large subtype of elliptical pellet, found only at that depth, was responsible for the majority of pellet carbon flux. Overall during 1990, fecal pellets were responsible for a depth-integrated annual average flux of 1.03 mgC/m**2/d, representing 18% of the total carbon flux. The proportion of vertical carbon flux attributed to fecal pellets varied from 3 to 35%, with higher values occurring during periods when the water column was vertically mixed. Especially during these times, fecal pellets are a critical conveyor of carbon to the deep sea in this region.

Supplement to: Carroll, Michael L; Miquel, Juan Carlos; Fowler, Scott W (1998): Seasonal patterns and depth-specific trends of zooplankton fecal pellet fluxes in the Northwestern Mediterranean Sea. Deep Sea Research Part I: Oceanographic Research Papers, 45(8), 1303-1318

Identifier
DOI https://doi.org/10.1594/PANGAEA.738627
Related Identifier https://doi.org/10.1016/S0967-0637(98)00013-2
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.738627
Provenance
Creator Carroll, Michael L ORCID logo; Miquel, Juan Carlos; Fowler, Scott W
Publisher PANGAEA
Publication Year 2002
Funding Reference European Commission https://doi.org/10.13039/501100000780 Crossref Funder ID ERBIC20-CT98-0103 Mediterranean Data Archaeology and Rescue; European Commission https://doi.org/10.13039/501100000780 Crossref Funder ID MAS3-CT98-0174 Mediterranean Data Archaeology and Rescue; Sixth Framework Programme https://doi.org/10.13039/100011103 Crossref Funder ID 36949 https://cordis.europa.eu/project/id/36949 Southern European Seas: Assessing and Modelling Ecosystem Changes
Rights Creative Commons Attribution 3.0 Unported; https://creativecommons.org/licenses/by/3.0/
OpenAccess true
Representation
Language English
Resource Type Supplementary Publication Series of Datasets; Collection
Format application/zip
Size 5 datasets
Discipline Ancient Cultures; Archaeology; Humanities
Spatial Coverage (7.252 LON, 43.428 LAT)
Temporal Coverage Begin 1990-01-18T00:00:00Z
Temporal Coverage End 1990-12-20T00:00:00Z