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Concept

Lac Victoria

Publications associées (17)

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

The Land-Water-Energy Nexus of Ruzizi River Dams (Lake Kivu Outflow, African Great Lakes Region): Status, Challenges, and Perspectives

Alfred Johny Wüest

Hydroelectric power (HP) represents the main source of electricity in Africa, including the Democratic Republic of Congo. The demand for new dam construction is high, and major projects are currently progressing through planning and implementation stages. ...

FRONTIERS MEDIA SA2022

Flushing the Lake Littoral Region: The Interaction of Differential Cooling and Mild Winds

Damien Bouffard, Hugo Nicolás Ulloa Sánchez, Tomy Doda

The interaction of a uniform cooling rate at the lake surface with sloping bathymetry efficiently drives cross-shore water exchanges between the shallow littoral and deep interior regions. The faster cooling rate of the shallows results in the formation of ...

AMER GEOPHYSICAL UNION2022

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

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

Wintertime Coastal Upwelling in Lake Geneva: An Efficient Transport Process for Deepwater Renewal in a Large, Deep Lake

David Andrew Barry, Ulrich Lemmin, Rafael Sebastian Reiss, Andrea Cimatoribus

Combining field measurements, 3‐D numerical modeling, and Lagrangian particle tracking, we investigated wind‐driven, Ekman‐type coastal upwelling during the weakly stratified winter period 2017/2018 in Lake Geneva, Western Europe's largest lake (max. depth ...

2020

Taxonomic revision of genus Fornasinius Bertoloni, 1853 with description of new taxa (Scarabaeidae: Cetoniinae)

Michele De Palma

The genus Fornasinius was established in 1853 by Giuseppe BERTOLONI to receive a taxon that was sufficiently distinct from the known representatives of the genus Goliathus Lamarck, 1801, to merit a different placement. Here, the type species of the genus, ...

2018

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

Effects of climate change on deepwater oxygen and winter mixing in a deep lake (Lake Geneva): Comparing observational findings and modeling

Alfred Johny Wüest, Damien Bouffard, Robert Vincent Schwefel

Low concentrations of dissolved oxygen remain a global concern regarding the ecological health of lakes and reservoirs. In addition to high nutrient loads, climate-induced changes in lake stratification and mixing represent additional anthropogenic menace ...

American Geophysical Union2016

Effects of climate change on deep-water oxygen and winter mixing in a deep lake (Lake Geneva)

Alfred Johny Wüest, Damien Bouffard, Robert Vincent Schwefel

Oxygen is the most important dissolved gas for lake ecosystems. Because low oxygen concentrations are an ongoing problem in many parts of the oceans and numerous lakes, oxygen depletion processes have been intensively studied over the last decades and were ...

2016

Optimizing turbine withdrawal from a tropical reservoir for improved water quality in downstream wetlands

Alfred Johny Wüest

Large reservoirs in the tropics act as efficient nutrient traps and often develop hypoxic conditions in the hypolimnion. Both effects may have severe implications for aquatic ecosystems, such as limited primary production in downstream riparian agriculture ...

American Geophysical Union2013

Methane formation and future extraction in Lake Kivu

Alfred Johny Wüest, Natacha Pasche

This chapter summarises the current knowledge on the vertical distribution of methane (CH4) and its formation in Lake Kivu. Additionally, we review the objectives and restrictions under consideration for sustainable extraction (safe, environmentally accept ...

Springer2012

Hypolimnetic Oxygen Depletion in Eutrophic Lakes

Alfred Johny Wüest, Beat Mueller

The oxygen-consuming processes in the hypolimnia of freshwater lakes leading to deep-water anoxia are still not well understood, thereby constraining suitable management concepts. This study presents data obtained from 11 eutrophic lakes and suggests a mod ...

Amer Chemical Soc2012

Spatial isolation favours the divergence in microcystin net production by Microcystis in Ugandan freshwater lakes

Karl Gademann, Cyril Portmann

It is generally agreed that the hepatotoxic microcystins (MCs) are the most abundant toxins produced by cyanobacteria in freshwater. In various freshwater lakes in East Africa MC-producing Microcystis has been reported to dominate the phytoplankton, howeve ...

2010

Hypolimnetic oxygen consumption by sediment-based reduced substances in former eutrophic lakes

Alfred Johny Wüest, Beat Mueller

We quantified the areal hypolimnetic mineralization rate (AHM; total areal hypolimnetic oxygen depletion including the formation of reduced substances) in two formerly eutrophic lakes based on 20 yr of water-column data collected during oligotrophication. ...

American Society of Limnology and Oceanography2010

Physical and biogeochemical limits to internal nutrient loading of meromictic Lake Kivu

Alfred Johny Wüest, Natacha Pasche, Beat Mueller

Lake Kivu is one of the large African Rift lakes situated between the Democratic Republic of the Congo and Rwanda. In its permanently stratified hypolimnion, unusually high methane concentrations have increased further in recent decades. Because methanogen ...

American Society of Limnology and Oceanography2009

Subgrid-Scale Dynamics of Water Vapour, Heat, and Momentum over a Lake

Marc Parlange, Ulrich Lemmin, Wolf Hendrik Huwald, Nikki Vercauteren

We examine the dynamics of turbulence subgrid (or sub-filter) scales over a lake surface and the implications for large-eddy simulations (LES) of the atmospheric boundary layer. The analysis is based on measurements obtained during the Lake-Atmosphere Turb ...

2008