Biogeography of Deep-sea benthic bacteria at regional scale (LTER HAUSGARTEN, Fram Strait, Arctic)

PLoS One. 2013 Sep 2;8(9):e72779. doi: 10.1371/journal.pone.0072779. eCollection 2013.

Abstract

Knowledge on spatial scales of the distribution of deep-sea life is still sparse, but highly relevant to the understanding of dispersal, habitat ranges and ecological processes. We examined regional spatial distribution patterns of the benthic bacterial community and covarying environmental parameters such as water depth, biomass and energy availability at the Arctic Long-Term Ecological Research (LTER) site HAUSGARTEN (Eastern Fram Strait). Samples from 13 stations were retrieved from a bathymetric (1,284-3,535 m water depth, 54 km in length) and a latitudinal transect (∼ 2,500 m water depth; 123 km in length). 454 massively parallel tag sequencing (MPTS) and automated ribosomal intergenic spacer analysis (ARISA) were combined to describe both abundant and rare types shaping the bacterial community. This spatial sampling scheme allowed detection of up to 99% of the estimated richness on phylum and class levels. At the resolution of operational taxonomic units (97% sequence identity; OTU3%) only 36% of the Chao1 estimated richness was recovered, indicating a high diversity, mostly due to rare types (62% of all OTU3%). Accordingly, a high turnover of the bacterial community was also observed between any two sampling stations (average replacement of 79% of OTU3%), yet no direct correlation with spatial distance was observed within the region. Bacterial community composition and structure differed significantly with increasing water depth along the bathymetric transect. The relative sequence abundance of Verrucomicrobia and Planctomycetes decreased significantly with water depth, and that of Deferribacteres increased. Energy availability, estimated from phytodetrital pigment concentrations in the sediments, partly explained the variation in community structure. Overall, this study indicates a high proportion of unique bacterial types on relatively small spatial scales (tens of kilometers), and supports the sampling design of the LTER site HAUSGARTEN to study bacterial community shifts in this rapidly changing area of the world's oceans.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arctic Regions
  • Bacteria*
  • Biodiversity
  • Ecosystem
  • Geologic Sediments / microbiology
  • Oceans and Seas
  • Water Microbiology

Grants and funding

Funding was provided by the European Research Council Advanced Investigator grant ABYSS 294757 and the Leibniz program of the Deutsche Forschungsgemeinschaft to AB. Additional funding came from the Helmholtz Association and Max Planck Society. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.