Publications associées à Bacillariophyta

Genomic and metabolic adaptations of biofilms to ecological windows of opportunity in glacier-fed streams

Tom Ian Battin, Hannes Markus Peter, Susheel Bhanu Busi, Grégoire Marie Octave Edouard Michoud, Leïla Ezzat, Massimo Bourquin, Matteo Tolosano, Tyler Joe Kohler, Stylianos Fodelianakis, Paraskevi Pramateftaki, Vincent Henri De Staercke, Michail Styllas, Martina Andrea Schön

In glacier-fed streams, ecological windows of opportunity allow complex microbial biofilms to develop and transiently form the basis of the food web, thereby controlling key ecosystem processes. Using metagenome-assembled genomes, we unravel strategies tha ...

Springer2022

Catchment characteristics and seasonality control the composition of microbial assemblages exported from three outlet glaciers of the Greenland Ice Sheet

Tyler Joe Kohler, Martina Andrea Schön

Glacial meltwater drains into proglacial rivers where it interacts with the surrounding landscape, collecting microbial cells as it travels downstream. Characterizing the composition of the resulting microbial assemblages in transport can inform us about i ...

Frontiers Media SA2022

Benthic Biofilms in Glacier-Fed Streams from Scandinavia to the Himalayas Host Distinct Bacterial Communities Compared with the Streamwater

Tom Ian Battin, Hannes Markus Peter, Susheel Bhanu Busi, Grégoire Marie Octave Edouard Michoud, Leïla Ezzat, Massimo Bourquin, Matteo Tolosano, Emmy Marie Oppliger, Jade Brandani, Paraskevi Pramateftaki, Virginia Tadei, Vincent Henri De Staercke, Tyler Joe Kohler, Michail Styllas, Stylianos Fodelianakis, Martina Andrea Schön

Microbial life in glacier-fed streams (GFSs) is dominated by benthic biofilms which fulfill critical ecosystem processes. However, it remains unclear how the bacterial communities of these biofilms assemble in stream ecosystems characterized by rapid turno ...

AMER SOC MICROBIOLOGY2022

Kleptoplast distribution, photosynthetic efficiency and sequestration mechanisms in intertidal benthic foraminifera

Anders Meibom, Charlotte Madeleine Nicole Lekieffre, Emmanuelle Geslin, Michael Kühl

Foraminifera are ubiquitously distributed in marine habitats, playing a major role in marine sediment carbon sequestration and the nitrogen cycle. They exhibit a wide diversity of feeding and behavioural strategies (heterotrophy, autotrophy and mixotrophy) ...

SPRINGERNATURE2022

Reaction of DMS and HOBr as a Sink for Marine DMS and an Inhibitor of Bromoform Formation

Urs von Gunten, Boris Droz

Recently, we suggested that hypobromous acid (HOBr) is a sink for the marine volatile organic sulfur compound dimethyl sulfide (DMS). However, HOBr is also known to react with reactive moieties of dissolved organic matter (DOM) such as phenolic compounds t ...

2021

From the Heroic Age to today: What diatoms from Shackleton's Nimrod expedition can tell us about the ecological trajectory of Antarctic ponds

Tyler Joe Kohler

Biological invasion and environmental change pose major threats to ecosystems. While long-term ecological change is commonly evaluated through sediment cores in lakes, it is generally not feasible for smaller ponds, and spatial resolution is limited. Here, ...

2021

Evaluating Alternative Metacommunity Hypotheses for Diatoms in the McMurdo Dry Valleys Using Simulations and Remote Sensing Data

Tyler Joe Kohler

Diatoms are diverse and widespread freshwater Eukaryotes that make excellent microbial subjects for addressing questions in metacommunity ecology. In the McMurdo Dry Valleys of Antarctica, the simple trophic structure of glacier-fed streams provides an ide ...

2020

A re-investigation of lake sediment diatoms from the Vestfold Hills, Antarctica, using an updated, fine-grained taxonomy

Tyler Joe Kohler

The non-marine diatom flora of the Antarctic continent is currently being revised as recent work within the Maritime and Sub-Antarctic regions has unveiled a number of new endemic species. The under reporting of endemic species is partially due to the hist ...

2020

Diel quenching of Southern Ocean phytoplankton fluorescence is related to iron limitation

Nina Schuback

Evaluation of photosynthetic competency in time and space is critical for better estimates and models of oceanic primary productivity. This is especially true for areas where the lack of iron (Fe) limits phytoplankton productivity, such as the Southern Oce ...

2020

Heterotrophic Foraminifera Capable of Inorganic Nitrogen Assimilation

Anders Meibom, Charlotte Madeleine Nicole Lekieffre, Emmanuelle Geslin

Nitrogen availability often limits biological productivity in marine systems, where inorganic nitrogen, such as ammonium is assimilated into the food web by bacteria and photoautotrophic eukaryotes. Recently, ammonium assimilation was observed in kleptopla ...

Frontiers Media SA2020

Carbon turnover and microbial activity in an artificial soil under imposed cyclic drainage and imbibition

Tatjana Milojevic

Water table fluctuations generate temporally and spatially dynamic physicochemical conditions that drive biogeochemical hot spots and hot moments in the vadose zone. However, their role in the cycling of soil C remains poorly known. Here, we present result ...

2020

Ammonium is the preferred source of nitrogen for planktonic foraminifer and their dinoflagellate symbionts

Anders Meibom, Charlotte Madeleine Nicole Lekieffre, Emmanuelle Geslin

The symbiotic planktonic foraminiferaOrbulina universainhabits open ocean oligotrophic ecosystems where dissolved nutrients are scarce and often limit biological productivity. It has previously been proposed thatO. universameets its nitrogen (N) requiremen ...

ROYAL SOC2020

Cycling of zinc and its isotopes across multiple zones of the Southern Ocean: Insights from the Antarctic Circumnavigation Expedition

Christel Sybille Hassler

Zinc (Zn) is an essential micronutrient, playing an important role in several key processes in marine phytoplankton. Here, we present the first high-resolution depth profiles for dissolved Zn and delta Zn-66 from all major zones of the Southern Ocean, coll ...

2020

High‐resolution spatial sampling identifies groundwater as driver of CO 2 dynamics in an Alpine stream network

Tom Ian Battin, Amber Joy Ulseth, Asa Lovisa Viktoria Horgby, Marta Boix Canadell

Inland waters are major sources of CO2 to the atmosphere. The origin of this CO2 is often elusive, especially in high‐altitude streams that remain poorly studied at present. Here we study the spatial and seasonal variations in streamwater CO2, its potentia ...

2019

Light availability impacts structure and function of phototrophic stream biofilms across domains and trophic levels

Tom Ian Battin

Phototrophic biofilms are ubiquitous in freshwater and marine environments where they are critical for biogeochemical cycling, food webs and in industrial applications. In streams, phototrophic biofilms dominate benthic microbial life and harbour an immens ...

Blackwell Publishing Ltd2018

Multiscale landscape genomic models to detect signatures of selection in the alpine plant Biscutella laevigata

Stéphane Joost, Kevin Leempoel

Plant species are known to adapt locally to their environment, particularly in mountainous areas where conditions can vary drastically over short distances. The climate of such landscapes being largely influenced by topography, using fine-scale models to e ...

2018

Surviving anoxia in marine sediments: The metabolic response of ubiquitous benthic foraminifera (Ammonia tepida)

Anders Meibom, Stéphane Laurent Escrig, Charlotte Madeleine Nicole Lekieffre, Emmanuelle Geslin

High input of organic carbon and/or slowly renewing bottom waters frequently create periods with low dissolved oxygen concentrations on continental shelves and in coastal areas; such events can have strong impacts on benthic ecosystems. Among the meiofauna ...

Public Library of Science2017

Sequestered Chloroplasts In The Benthic Foraminifer Haynesina Germanica: Cellular Organization, Oxygen Fluxes And Potential Ecological Implications

Charlotte Madeleine Nicole Lekieffre, Emmanuelle Geslin

Haynesina germanica is a coastal benthic foraminifer known to sequester chloroplasts from benthic pennate diatoms. This study investigates its cellular organization, as well as the oxygen consumption and production rates under dark and light conditions. Th ...

2017

Allelopathic Activity of the Iron Chelator Anachelin-A Molecular Hybrid with a Dual Mode of Action

Karl Gademann

One of the compounds suggested to be responsible for the cyanobacterial dominance over competing green algae is identified. Evidence is provided on the molecular, chemical level that the iron chelator anachelin from the cyanobacterium Anabaena cylindrica p ...

Wiley-V C H Verlag Gmbh2016

Silver nanoparticle effects on simple stream food webs and ecosystem processes : periphyton-grazer system

Carmen Omayra Gil Allué

With the global nanotechnology market growing rapidly, nanomaterials are being increasingly released into aquatic environments, where they can undergo modifications and sedimentation, which will put benthic organisms at risk. Of particular interest is the ...

EPFL2015