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Concept

Hypoxia (environmental)

Publications associées (21)

Near-bed stratification controls bottom hypoxia in ice-covered alpine lakes

Damien Bouffard, Hugo Nicolás Ulloa Sánchez, Camille Roland Marie Minaudo, Janine Rüegg, Nicolas Thomas Georges Escoffier, Tomy Doda, Hannah Elisa Chmiel, Pascal Perolo

In ice-covered lakes, near-bottom oxygen concentration decreases for most of the wintertime, sometimes down to the point that bottom waters become hypoxic. Studies insofar have reached divergent conclusions on whether climate change limits or reinforces th ...

American Society of Limnology and Oceanography2023

Genomic insights into the coupling of a Chlorella-like microeukaryote and sulfur bacteria in the chemocline of permanently stratified Lake Cadagno

Christel Sybille Hassler

Meromictic Lake Cadagno is a permanently stratified system with a persistent microbial bloom within the oxic-anoxic boundary called the chemocline. The association between oxygenic and anoxygenic photosynthesis within the chemocline has been known for at l ...

SPRINGERNATURE2023

Iron Reduction in Profundal Sediments of Ultraoligotrophic Lake Tahoe under Oxygen-Limited Conditions

Meret Aeppli

Increased periods of bottom water anoxia in deep temperate lakes due to decreasing frequency and depth of water column mixing in a warming climate may result in the reductive dissolution of iron minerals and increased flux of nutrients from the sediment in ...

2023

Spatially Explicit Linkages Between Redox Potential Cycles and Soil Moisture Fluctuations

Andrea Rinaldo, Rizlan Bernier-Latmani, Paolo Benettin, Manon Frutschi, Mitra Asadollahi, Simiao Wang, Filippo Miele

Reduction-oxidation cycles measured through soil redox potential (Eh) are associated with dynamic soil microbial activity. Understanding changes in the composition of, and resource use by, soil microbial communities requires Eh predictability under shiftin ...

American Geophysical Union2023

Consider the Anoxic Microsite: Acknowledging and Appreciating Spatiotemporal Redox Heterogeneity in Soils and Sediments

Meret Aeppli

Reduction-oxidation (redox) reactions underlie essentially all biogeochemical cycles. Like most soil properties and processes, redox is spatiotemporally heterogeneous. However, unlike other soil features, redox heterogeneity has yet to be incorporated into ...

AMER CHEMICAL SOC2023

Wind‐Induced Hypolimnetic Upwelling Between the Multi‐Depth Basins of Lake Geneva During Winter: An Overlooked Deepwater Renewal Mechanism?

David Andrew Barry, Ulrich Lemmin, Rafael Sebastian Reiss

Combining field observations, 3D hydrodynamic modeling, and particle tracking, we investigated wind-induced interbasin exchange between the Petit Lac (PL) (depth 75 m) and Grand Lac (GL) (depth 309 m) basins of Lake Geneva in early winter. Following a stro ...

2022

Evidence that Pacific tuna mercury levels are driven by marine methylmercury production and anthropogenic inputs

Hélène Paule Angot

Pacific Ocean tuna is among the most-consumed seafood products but contains relatively high levels of the neurotoxin methylmercury. Limited observations suggest tuna mercury levels vary in space and time, yet the drivers are not well understood. Here, we m ...

National Academy of Sciences2022

Detritus-hosted methanogenesis sustains the methane paradox in an alpine lake

Damien Bouffard, Oscar Rodrigo Sepúlveda Steiner

Accumulation of methane in oxic waters of lakes and the ocean has been widely reported. Despite the importance for the greenhouse gas budget, mechanistic controls of such "methane paradox" remain elusive. Here, we use a combination of CH4 concentration and ...

American Society of Limnology and Oceanography2022

Dynamics of wind-induced coastal upwelling and interbasin exchange in Lake Geneva during winter: Implications for deepwater renewal

Rafael Sebastian Reiss

Water quality in lakes is closely linked to hydrodynamics and often dominated by stratification, limiting the exchange between the epi- and hypolimnion. Thus, the vertical redistribution of biogeochemical tracers such as dissolved oxygen and nutrients by c ...

EPFL2021

Catalytic effects of photogenerated Fe(II) on the ligand-controlled dissolution of Iron(hydr)oxides by EDTA and DFOB

Janet Gordon Hering

Low bioavailability of iron due to poor solubility of iron(hydr)oxides limits the growth of microorganisms and plants in soils and aquatic environments. Previous studies described accelerated dissolution of iron(hydr)oxides under continuous illumination, b ...

Pergamon-Elsevier Science Ltd2021

Towards simple tools to assess functional effects of contaminants on natural microbial and invertebrate sediment communities

Benoît Jean Dominique Ferrari, Sophie Campiche, Maria del Carmen Casado Martinez

Surface sediments can accumulate contaminants that affect microorganisms and invertebrates and disturb benthic ecological functions. However, effects of contaminants on ecological functions supported by sediment communities are understudied. Here, we teste ...

SPRINGER HEIDELBERG2020

Hypolimnetic oxygen depletion rates in deep lakes: Effects of trophic state and organic matter accumulation

Alfred Johny Wüest, Robert Vincent Schwefel, Beat Mueller

This study investigated the consumption of oxygen (O-2) in 11 European lakes ranging from 48 m to 372 m deep. In lakes less than similar to 100 m deep, the main pathways for O-2 consumption were organic matter (OM) mineralization at the sediment surface an ...

American Society of Limnology and Oceanography2020

Long-term impacts of nutrient control, climate change, and invasive clams on phytoplankton and cyanobacteria biomass in a large temperate river

Camille Roland Marie Minaudo

Recent studies suggest that climate change, with warmer water temperatures and lower and longer low flows, may enhance harmful planktic cyanobacterial growth in lakes and large rivers. Concomitantly, controlling nutrient loadings has proven effective in re ...

2020

As release under the microbial sulfate reduction during redox oscillations in the upper Mekong delta aquifers, Vietnam: A mechanistic study

Rizlan Bernier-Latmani, Manon Frutschi

The impact of seasonal fluctuations linked to monsoon and irrigation generates redox oscillations in the subsurface, influencing the release of arsenic (As) in aquifers. Here, the biogeochemical control on As mobility was investigated in batch experiments ...

2019

Modelling pumped-storage effects on thermal structure, ice cover and water quality of lakes and reservoirs in a changing climate

Ulrike Kobler

New renewable electricity is nowadays often generated by photovoltaics and wind. Yet, their intermittent nature calls for energy storage, which is today still provided to ~95% by pumped-storage (PS) hydropower plants. However, PS is known to affect abiotic ...

EPFL2019

Using small-scale measurements to estimate hypolimnetic oxygen depletion in a deep lake

Alfred Johny Wüest, Damien Bouffard, Robert Vincent Schwefel

Low oxygen concentrations in lakes and reservoirs are an ongoing environmental concern, particularly in light of increasing anthropogenic activity and climate change. Oxygen depletion processes in lakes are still not completely understood and a variety of ...

American Society of Limnology and Oceanography2018

Oxygen depletion in Lake Geneva

Robert Vincent Schwefel

Low oxygen concentrations remain a global concern for the ecological health of lakes. High nutrient inputs and climate-induced changes in stratification and mixing are anthropogenic threats which largely impact aquatic oxygen budgets and overall ecosystem ...

EPFL2017

RETRACTED: Water hyacinth a potential source for value addition: An overview

Edgard Gnansounou

Water hyacinth a fresh water aquatic plant is considered as a noxious weed in many parts of the world since it grows very fast and depletes nutrients and oxygen from water bodies adversely affecting the growth of both plants and animals. Hence conversion o ...

Elsevier2017

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

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

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

Scaling oxygen microprofiles at the sediment interface of deep stratified waters

Alfred Johny Wüest, Damien Bouffard, Robert Vincent Schwefel

Dissolved oxygen microprofiles at the sediment-water interface of Lake Geneva were measured concurrently with velocities 0.25 to 2m above the sediment. The measurements and scaling analyses indicate dissolved oxygen fluctuations and turbulent fluxes in exc ...

American Geophysical Union2017