Zooplankton data of M83/1

DOI

Oxygen-deficient waters in the ocean, generally referred to as oxygen minimum zones (OMZ), are expected to expand as a consequence of global climate change. Poor oxygenation is promoting microbial loss of inorganic nitrogen (N) and increasing release of sediment-bound phosphate (P) into the water column. These intermediate water masses, nutrient-loaded but with an N deficit relative to the canonical N:P Redfield ratio of 16:1, are transported via coastal upwelling into the euphotic zone. To test the impact of nutrient supply and nutrient stoichiometry on production, partitioning and elemental composition of dissolved (DOC, DON, DOP) and particulate (POC, PON, POP) organic matter, three nutrient enrichment experiments were conducted with natural microbial communities in shipboard mesocosms, during research cruises in the tropical waters of the southeast Pacific and the northeast Atlantic. Maximum accumulation of POC and PON was observed under high N supply conditions, indicating that primary production was controlled by N availability. The stoichiometry of microbial biomass was unaffected by nutrient N:P supply during exponential growth under nutrient saturation, while it was highly variable under conditions of nutrient limitation and closely correlated to the N:P supply ratio, although PON:POP of accumulated biomass generally exceeded the supply ratio. Microbial N:P composition was constrained by a general lower limit of 5:1. Channelling of assimilated P into DOP appears to be the mechanism responsible for the consistent offset of cellular stoichiometry relative to inorganic nutrient supply and nutrient drawdown, as DOP build-up was observed to intensify under decreasing N:P supply. Low nutrient N:P conditions in coastal upwelling areas overlying O2-deficient waters seem to represent a net source for DOP, which may stimulate growth of diazotrophic phytoplankton. These results demonstrate that microbial nutrient assimilation and partitioning of organic matter between the particulate and the dissolved phase are controlled by the N:P ratio of upwelled nutrients, implying substantial consequences for nutrient cycling and organic matter pools in the course of decreasing nutrient N:P stoichiometry.

Supplement to: Hauss, Helena; Franz, Jasmin; Hansen, Thomas; Struck, Ulrich; Sommer, Ulrich (2013): Relative inputs of upwelled and atmospheric nitrogen to the eastern tropical North Atlantic food web: Spatial distribution of d15N in mesozooplankton and relation to dissolved nutrient dynamics. Deep Sea Research Part I: Oceanographic Research Papers, 75, 135-145

Identifier
DOI https://doi.org/10.1594/PANGAEA.821908
Related Identifier https://doi.org/10.1016/j.dsr.2013.01.010
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.821908
Provenance
Creator Hauss, Helena ORCID logo; Franz, Jasmin; Hansen, Thomas; Struck, Ulrich; Sommer, Ulrich
Publisher PANGAEA
Publication Year 2012
Funding Reference German Research Foundation https://doi.org/10.13039/501100001659 Crossref Funder ID 27542298 https://gepris.dfg.de/gepris/projekt/27542298 Climate - Biogeochemistry Interactions in the Tropical Ocean
Rights Creative Commons Attribution 3.0 Unported; https://creativecommons.org/licenses/by/3.0/
OpenAccess true
Representation
Resource Type Supplementary Publication Series of Datasets; Collection
Format application/zip
Size 3 datasets
Discipline Biogeochemistry; Biospheric Sciences; Geosciences; Natural Sciences
Spatial Coverage (-28.003W, 1.966S, -15.044E, 17.650N)
Temporal Coverage Begin 2010-10-18T05:20:00Z
Temporal Coverage End 2010-11-11T10:06:00Z