Seasonal patterns of bacterial communities in the coastal brackish sediments of the Gulf of Finland, Baltic Sea

Research output: Contribution to journalArticleScientificpeer-review

Abstract

Coastal areas are critical in mitigating the impact of nutrient runoffs and downstream eutrophication of aquatic ecosystems. In the Gulf of Finland, the easternmost sub-basin of the Baltic Sea, seasonal and long-term oxygen depletion at the surface of the sediment feeds back the eutrophication loop by promoting the release of nutrients locked in the sediment matrix. In order to understand how the bacterial community responds to the seasonal variations, we sequenced ribosomal gene fragments from the top sediment layer at two coastal sites in southern Finland in spring, summer and late autumn during two consecutive years. Analysis of the samples collected at a shallow (11 m) and deep site (33 m) revealed that the overall community composition was rather constant over time with an extensive collection of shared operational taxonomic units (OTU) between sites. The dominant taxa were related to organo-heterotrophs and sulfate reducers and the variation in community structure was linked to the availability of organic matter in the surface sediment. Proteobacteria formed the most abundant and diverse group. The taxa characteristic of spring samples belonged primarily to Actinobacteria, possibly of fresh water origin and linked to humic carbon. Summer communities were characterized by an increase in the number of reads associated with heterotrophic bacteria such as Bacteroidetes which feed on labile organic matter from spring bloom. Taxa typical of autumn samples were linked to Cyanobacteria and other bloom-forming bacteria from the overlying water and to bacteria feeding on organic matter drifting from the phytal zone. (C) 2015 Elsevier Ltd. All rights reserved.
Original languageEnglish
JournalEstuarine, Coastal and Shelf Science
Volume165
Pages (from-to)86-96
Number of pages11
ISSN0272-7714
DOIs
Publication statusPublished - 11 Sep 2015
MoE publication typeA1 Journal article-refereed

Fields of Science

  • 1181 Ecology, evolutionary biology
  • Nucleic acids
  • Bacteria
  • Sediment
  • Microbes
  • Population structure
  • Population dynamics
  • Pyrosequencing
  • 16S rDNA
  • SULFATE-REDUCING BACTERIA
  • DISSOLVED ORGANIC-MATTER
  • COMPLETE GENOME SEQUENCE
  • RIBOSOMAL-RNA SEQUENCES
  • SP-NOV.
  • GEN. NOV.
  • MICROBIAL DIVERSITY
  • EMENDED DESCRIPTION
  • PHYLUM VERRUCOMICROBIA
  • HYDROTHERMAL VENT

Cite this

@article{37b5c6990d5041aabbdb758efba9a654,
title = "Seasonal patterns of bacterial communities in the coastal brackish sediments of the Gulf of Finland, Baltic Sea",
abstract = "Coastal areas are critical in mitigating the impact of nutrient runoffs and downstream eutrophication of aquatic ecosystems. In the Gulf of Finland, the easternmost sub-basin of the Baltic Sea, seasonal and long-term oxygen depletion at the surface of the sediment feeds back the eutrophication loop by promoting the release of nutrients locked in the sediment matrix. In order to understand how the bacterial community responds to the seasonal variations, we sequenced ribosomal gene fragments from the top sediment layer at two coastal sites in southern Finland in spring, summer and late autumn during two consecutive years. Analysis of the samples collected at a shallow (11 m) and deep site (33 m) revealed that the overall community composition was rather constant over time with an extensive collection of shared operational taxonomic units (OTU) between sites. The dominant taxa were related to organo-heterotrophs and sulfate reducers and the variation in community structure was linked to the availability of organic matter in the surface sediment. Proteobacteria formed the most abundant and diverse group. The taxa characteristic of spring samples belonged primarily to Actinobacteria, possibly of fresh water origin and linked to humic carbon. Summer communities were characterized by an increase in the number of reads associated with heterotrophic bacteria such as Bacteroidetes which feed on labile organic matter from spring bloom. Taxa typical of autumn samples were linked to Cyanobacteria and other bloom-forming bacteria from the overlying water and to bacteria feeding on organic matter drifting from the phytal zone. (C) 2015 Elsevier Ltd. All rights reserved.",
keywords = "1181 Ecology, evolutionary biology, Nucleic acids, Bacteria, Sediment, Microbes, Population structure, Population dynamics, Pyrosequencing, 16S rDNA, SULFATE-REDUCING BACTERIA, DISSOLVED ORGANIC-MATTER, COMPLETE GENOME SEQUENCE, RIBOSOMAL-RNA SEQUENCES, SP-NOV., GEN. NOV., MICROBIAL DIVERSITY, EMENDED DESCRIPTION, PHYLUM VERRUCOMICROBIA, HYDROTHERMAL VENT",
author = "Adrien Vetterli and Kirsi Hyyti{\"a}inen and Minttu Ahjos and Petri Auvinen and Lars Paulin and Susanna Hietanen and Elina Leskinen",
year = "2015",
month = "9",
day = "11",
doi = "10.1016/j.ecss.2015.07.049",
language = "English",
volume = "165",
pages = "86--96",
journal = "Estuarine, Coastal and Shelf Science",
issn = "0272-7714",
publisher = "ACADEMIC PRESS INC ELSEVIER SCIENCE",

}

TY - JOUR

T1 - Seasonal patterns of bacterial communities in the coastal brackish sediments of the Gulf of Finland, Baltic Sea

AU - Vetterli, Adrien

AU - Hyytiäinen, Kirsi

AU - Ahjos, Minttu

AU - Auvinen, Petri

AU - Paulin, Lars

AU - Hietanen, Susanna

AU - Leskinen, Elina

PY - 2015/9/11

Y1 - 2015/9/11

N2 - Coastal areas are critical in mitigating the impact of nutrient runoffs and downstream eutrophication of aquatic ecosystems. In the Gulf of Finland, the easternmost sub-basin of the Baltic Sea, seasonal and long-term oxygen depletion at the surface of the sediment feeds back the eutrophication loop by promoting the release of nutrients locked in the sediment matrix. In order to understand how the bacterial community responds to the seasonal variations, we sequenced ribosomal gene fragments from the top sediment layer at two coastal sites in southern Finland in spring, summer and late autumn during two consecutive years. Analysis of the samples collected at a shallow (11 m) and deep site (33 m) revealed that the overall community composition was rather constant over time with an extensive collection of shared operational taxonomic units (OTU) between sites. The dominant taxa were related to organo-heterotrophs and sulfate reducers and the variation in community structure was linked to the availability of organic matter in the surface sediment. Proteobacteria formed the most abundant and diverse group. The taxa characteristic of spring samples belonged primarily to Actinobacteria, possibly of fresh water origin and linked to humic carbon. Summer communities were characterized by an increase in the number of reads associated with heterotrophic bacteria such as Bacteroidetes which feed on labile organic matter from spring bloom. Taxa typical of autumn samples were linked to Cyanobacteria and other bloom-forming bacteria from the overlying water and to bacteria feeding on organic matter drifting from the phytal zone. (C) 2015 Elsevier Ltd. All rights reserved.

AB - Coastal areas are critical in mitigating the impact of nutrient runoffs and downstream eutrophication of aquatic ecosystems. In the Gulf of Finland, the easternmost sub-basin of the Baltic Sea, seasonal and long-term oxygen depletion at the surface of the sediment feeds back the eutrophication loop by promoting the release of nutrients locked in the sediment matrix. In order to understand how the bacterial community responds to the seasonal variations, we sequenced ribosomal gene fragments from the top sediment layer at two coastal sites in southern Finland in spring, summer and late autumn during two consecutive years. Analysis of the samples collected at a shallow (11 m) and deep site (33 m) revealed that the overall community composition was rather constant over time with an extensive collection of shared operational taxonomic units (OTU) between sites. The dominant taxa were related to organo-heterotrophs and sulfate reducers and the variation in community structure was linked to the availability of organic matter in the surface sediment. Proteobacteria formed the most abundant and diverse group. The taxa characteristic of spring samples belonged primarily to Actinobacteria, possibly of fresh water origin and linked to humic carbon. Summer communities were characterized by an increase in the number of reads associated with heterotrophic bacteria such as Bacteroidetes which feed on labile organic matter from spring bloom. Taxa typical of autumn samples were linked to Cyanobacteria and other bloom-forming bacteria from the overlying water and to bacteria feeding on organic matter drifting from the phytal zone. (C) 2015 Elsevier Ltd. All rights reserved.

KW - 1181 Ecology, evolutionary biology

KW - Nucleic acids

KW - Bacteria

KW - Sediment

KW - Microbes

KW - Population structure

KW - Population dynamics

KW - Pyrosequencing

KW - 16S rDNA

KW - SULFATE-REDUCING BACTERIA

KW - DISSOLVED ORGANIC-MATTER

KW - COMPLETE GENOME SEQUENCE

KW - RIBOSOMAL-RNA SEQUENCES

KW - SP-NOV.

KW - GEN. NOV.

KW - MICROBIAL DIVERSITY

KW - EMENDED DESCRIPTION

KW - PHYLUM VERRUCOMICROBIA

KW - HYDROTHERMAL VENT

U2 - 10.1016/j.ecss.2015.07.049

DO - 10.1016/j.ecss.2015.07.049

M3 - Article

VL - 165

SP - 86

EP - 96

JO - Estuarine, Coastal and Shelf Science

JF - Estuarine, Coastal and Shelf Science

SN - 0272-7714

ER -