Title :

Hydrological pulse regulating the bacterial heterotrophic metabolism between Amazonian mainstems and floodplain lakes

Author(s) :

Vidal, Luciana O. [Auteur]
Universidade Estadual do Norte Fluminense Darcy Ribeiro [UENF]
Abril, Gwenaël [Auteur]
Environnements et Paléoenvironnements OCéaniques [EPOC]
Artigas, Luiz F. [Auteur]
Université du Littoral Côte d'Opale [ULCO]
Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 [LOG]
Melo, Michaela L. [Auteur]
Universidade Federal de São Carlos [São Carlos] [UFSCar]
Bernardes, Marcelo C. [Auteur]
Universidade Federal Fluminense [Rio de Janeiro] [UFF]
Lobão, Lúcia M. [Auteur]
Universidade Federal de Juiz de Fora [UFJF]
Reis, Mariana C. [Auteur]
Universidade Federal de São Carlos [São Carlos] [UFSCar]
Moreira-Turcq, Patrícia [Auteur]
Géosciences Environnement Toulouse [GET]
Benedetti, Marc [Auteur]
Institut de Physique du Globe de Paris [IPGP (UMR_7154)]
Tornisielo, Valdemar L. [Auteur]
Universidade Federal de São Paulo
Roland, Fabio [Auteur]
Universidade Federal de Juiz de Fora [UFJF]

Journal title :

Frontiers in Microbiology

Pages :

1054

Publisher :

Frontiers Media

Publication date :

2015-09

ISSN :

1664-302X

English keyword(s) :

bacterial production
bacterial respiration
bacterial carbon demand
bacterial growth efficiency
hydrological pulse
Amazonian fresh water ecosystems

HAL domain(s) :

Sciences du Vivant [q-bio]/Microbiologie et Parasitologie/Bactériologie
Sciences du Vivant [q-bio]/Ecologie, Environnement/Ecosystèmes

English abstract : [en]

We evaluated in situ rates of bacterial carbon processing in Amazonian floodplain lakes and mainstems, during both high water (HW) and low water (LW) phases (p < 0.05). Our results showed that bacterial production (BP) ...
Show more >We evaluated in situ rates of bacterial carbon processing in Amazonian floodplain lakes and mainstems, during both high water (HW) and low water (LW) phases (p < 0.05). Our results showed that bacterial production (BP) was lower and more variable than bacterial respiration, determined as total respiration. Bacterial carbon demand was mostly accounted by BR and presented the same pattern that BR in both water phases. Bacterial growth efficiency (BGE) showed a wide range (0.2-23%) and low mean value of 3 and 6%, (in HW and LW, respectively) suggesting that dissolved organic carbon was mostly allocated to catabolic metabolism. However, BGE was regulated by BP in LW phase. Consequently, changes in BGE showed the same pattern that BP. In addition, the hydrological pulse effects on mainstems and floodplains lakes connectivity were found for BP and BGE in LW. Multiple correlation analyses revealed that indexes of organic matter (OM) quality (chlorophyll-a, N stable isotopes and C/N ratios) were the strongest seasonal drivers of bacterial carbon metabolism. Our work indicated that: (i) the bacterial metabolism was mostly driven by respiration in Amazonian aquatic ecosystems resulting in low BGE in either high or LW phase; (ii) the hydrological pulse regulated the bacterial heterotrophic metabolism between Amazonian mainstems and floodplain lakes mostly driven by OM quality.Show less >

Language :

Anglais

Peer reviewed article :

Oui

Audience :

Internationale

Popular science :

Non

ANR Project :

CARBon biogeochemistry and atmospheric exchanges in the AMAzon river system

Collections :

• Laboratoire d'Océanologie et de Géosciences (LOG) - UMR 8187

Source :

Harvested from HAL