Biomass and stable isotope composition of plankton in five size fractions along a zonal transect (24°N) from the Canary Islands to Florida in January-March 2011

DOI

The spatial variability of biomass and stable isotopes in plankton size fractions in the upper 200 m was studied in a high spatial resolution transect along 24°N from Canary Islands to Florida (January - March 2011) during Leg 8 of the Malaspina-2010 expedition (http://www.expedicionmalaspina.es) to determine nitrogen and carbon sources. Plankton samples were collected by vertical tows of a microplankton net (40 mm mesh size) and a mesoplankton net (200 mm mesh size) through the upper 200 m of the water column. Sampling was between 10:00 and 16:00 h GMT. Plankton was separated into five size fractions (40 - 200, 200 - 500, 500 - 1000, 1000 - 2000 and > 2000 mm) by gentle filtration of the samples by a graded series of nylon sieves (2000, 1000, 500, 200 and 40 mm). Large gelatinous organisms were removed before filtration. Aliquots for each size fraction were collected on pre-weighed glass-fibre filters, dried (60°C, 48 h) and stored in a desiccator before determination of biomass (dry weight), carbon and nitrogen content and natural abundance of stable carbon and nitrogen isotopes ashore. Vertical advection of waters predominated in lateral zones while the central Atlantic (30-70°W) was characterized by a strong stratification and oligotrophic surface waters. Plankton biomass was low in the central zone and high in both eastern and western sides, with most of the variability due to either large (>2000 µm) and small plankton (<500 µm). Carbon isotopes reflected mainly the advection the deep water in lateral zones. Stable nitrogen isotopes showed a nearly symmetrical spatial distribution in all fractions, with the lowest values (delta15N 50% of organic nitrogen in the central zone, and even >30% in eastern and western zones. The impact of diazotrophy increased with the size of the organisms, supporting the wide participation of all trophic levels in the processing of recently fixed nitrogen. These results indicate that atmospheric sources of carbon and nitrogen prevail over deep water sources in the subtropical North Atlantic and that the zone influenced by diazotrophy is much larger than reported in previous studies.

Data were collected in the framework of EURO-BASIN and MALASPINA-2010

Supplement to: Mompeán, Carmen; Bode, Antonio; Benítez-Barrios, Verónica M; Domínguez-Yanes, J Francisco; Escánez, José; Eugenio, Fraile-Nuez (2013): Spatial patterns of plankton biomass and stable isotopes reflect the influence of the nitrogen-fixer Trichodesmium along the subtropical North Atlantic. Journal of Plankton Research, 35(3), 513-525

Identifier
DOI https://doi.org/10.1594/PANGAEA.816451
Related Identifier https://doi.org/10.1093/plankt/fbt011
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.816451
Provenance
Creator Bode, Antonio ORCID logo
Publisher PANGAEA
Publication Year 2013
Funding Reference Ministerio de Ciencia e Innovación https://doi.org/10.13039/501100004837 Crossref Funder ID CSD2008-00077 Circumnavigation expedition Malaspina 2010: Global Change and Exploration of Biodiversity of the Global Ocean; Seventh Framework Programme https://doi.org/10.13039/100011102 Crossref Funder ID 264933 https://cordis.europa.eu/project/id/264933 Basin Scale Analysis, Synthesis and Integration
Rights Creative Commons Attribution 3.0 Unported; https://creativecommons.org/licenses/by/3.0/
OpenAccess true
Representation
Language English
Resource Type Supplementary Dataset; Dataset
Format text/tab-separated-values
Size 1161 data points
Discipline Earth System Research
Spatial Coverage (-79.566W, 24.486S, -15.348E, 27.128N); Subtropical North Atlantic
Temporal Coverage Begin 2011-01-29T11:23:00Z
Temporal Coverage End 2011-03-13T21:33:00Z