Marine bacterial richness increases towards higher latitudes in the eastern Indian Ocean

Fuente: PANGAEA
Saved in:
Bibliographic Details
Main Authors: Raes, Eric J, Bodrossy, Levente, Van De Kamp, Jodie, Bissett, Andrew, Waite, Anya M
Format: Dataset Open Access
Language:en
Published: PANGAEA 2017
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1867170472382169088
author Raes, Eric J
Bodrossy, Levente
Van De Kamp, Jodie
Bissett, Andrew
Waite, Anya M
author_facet Raes, Eric J
Bodrossy, Levente
Van De Kamp, Jodie
Bissett, Andrew
Waite, Anya M
collection Datos científicos de ciencias marinas y ambientales
contents Abstract: We investigated the bacterial community structure in surface waters along a 2500 km transect in the eastern Indian Ocean. Using high throughput sequencing of the 16S rRNA gene we measured a significant latitudinal increase in bacterial richness from 800 to 1400 OTUs (42% increase; r2=0.65; p<0.001) from the tropical Timor Sea to the colder temperate waters. Total dissolved inorganic nitrogen, chl a, phytoplankton community structure and primary productivity strongly correlated with bacterial richness (all p<0.01). Our data suggest that primary productivity drives greater bacterial richness. Because, N2-fixation accounts for up to 50% of new production in this region we tested whether higher N2-fixation rates are linked to a greater nifH diversity. The nifH diversity was dominated by heterotrophic Alphaproteobacteria, Betaproteobacteria, and Gammaproteobacteria. We did not found any mechanistic links between nifH amplicon data, bacterial richness and primary productivity due to the overall low nifH evenness in this region. Scientific statement: Geographic gradients of marine microbial diversity is currently thought to be explained by two mechanisms, 1) diversity increases with increased productivity, and 2) it increases with increasing temperature. However, conclusive evidence for these mechanisms has been lacking from studies that span gradients in both, and it is unclear which organisms are responsible for the changes in diversity along these gradients. Here we present the first analysis of bacterial richness along the West Australian boundary current, the Leeuwin Current. Our analysis of bacterial richness along a latitudinal gradient in the eastern Indian Ocean shows support for the productivity mechanism rather than the temperature mechanism. Further, we show that bacterial richness increases towards the productive temperate waters are driven by productive eukaryotes (NO3- based) and heterotrophic N2-fixers.
format Dataset Open Access
id pangaea_https___doi_org_10_1594_PANGAEA_882511
institution PANGAEA
language en
publishDate 2017
publisher PANGAEA
record_format pangaea
spellingShingle Marine bacterial richness increases towards higher latitudes in the eastern Indian Ocean
Raes, Eric J
Bodrossy, Levente
Van De Kamp, Jodie
Bissett, Andrew
Waite, Anya M
AWI_BioOce; Biological Oceanography @ AWI
Abstract: We investigated the bacterial community structure in surface waters along a 2500 km transect in the eastern Indian Ocean. Using high throughput sequencing of the 16S rRNA gene we measured a significant latitudinal increase in bacterial richness from 800 to 1400 OTUs (42% increase; r2=0.65; p<0.001) from the tropical Timor Sea to the colder temperate waters. Total dissolved inorganic nitrogen, chl a, phytoplankton community structure and primary productivity strongly correlated with bacterial richness (all p<0.01). Our data suggest that primary productivity drives greater bacterial richness. Because, N2-fixation accounts for up to 50% of new production in this region we tested whether higher N2-fixation rates are linked to a greater nifH diversity. The nifH diversity was dominated by heterotrophic Alphaproteobacteria, Betaproteobacteria, and Gammaproteobacteria. We did not found any mechanistic links between nifH amplicon data, bacterial richness and primary productivity due to the overall low nifH evenness in this region. Scientific statement: Geographic gradients of marine microbial diversity is currently thought to be explained by two mechanisms, 1) diversity increases with increased productivity, and 2) it increases with increasing temperature. However, conclusive evidence for these mechanisms has been lacking from studies that span gradients in both, and it is unclear which organisms are responsible for the changes in diversity along these gradients. Here we present the first analysis of bacterial richness along the West Australian boundary current, the Leeuwin Current. Our analysis of bacterial richness along a latitudinal gradient in the eastern Indian Ocean shows support for the productivity mechanism rather than the temperature mechanism. Further, we show that bacterial richness increases towards the productive temperate waters are driven by productive eukaryotes (NO3- based) and heterotrophic N2-fixers.
title Marine bacterial richness increases towards higher latitudes in the eastern Indian Ocean
topic AWI_BioOce; Biological Oceanography @ AWI
url https://doi.org/10.1594/PANGAEA.882511