Publications by Alfred Johny Wüest

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Oxygen is the most important element in natural waters for any higher aquatic life, such as fish. As with humans, almost all members of aquatic ecosystems need oxygen to breathe. Building on this, treatment of drinking water is easier for oxic than for ano ...

Three-dimensional direct numerical simulations are performed that give us an in-depth account of the evolution and structure of the double-diffusive interface. We examine the diffusive convection regime, which, in the oceanographically relevant case, consi ...

A detailed budget of the fluxes of bio-available phosphorus (bio-P) was established for the ultra-oligotrophic Lake Brienz (Switzerland) and its catchment. Lake Brienz is a cold, deep oligotrophic peri-alpine lake that receives an annual load of approximat ...

The fragility of thin Clark-type glass microelectrodes used in aquatic eddy covariance measurements of benthic oxygen fluxes is a challenge when using this powerful technique. This study presents a new fast-responding dual oxygen-temperature sensor for edd ...

Field data from a stratified lake demonstrate that buoyancy-driven convective mixing can be an important mechanism for the formation of well-mixed bottom boundary layers (BBLs) on slopes. Convective turbulence is caused by differential transport of stratif ...

Benthic fluxes of dissolved oxygen are measured in a shallow reservoir using the eddy correlation technique. Flux variations depict the diurnal production-consumption cycle, with daytime oxygen release following the solar radiation trend. The average night ...

[1] Nutrient transfer from soils to surface waters is associated with large, hydrologically induced fluctuations. Consequently, stream-based estimation of long-term changes in nutrient leaching is masked by variations of stream discharge. Using high-resolu ...

The understanding of physical dynamics is crucial to provide scientifically credible information on lake ecosystem management. We show how the combination of in situ observations, remote sensing data, and three-dimensional hydrodynamic (3D) numerical simul ...

The rates of gross primary production (GPP), ecosystem respiration (R), and net ecosystem production (NEP) provide quantitative information about the cycling of carbon and energy in aquatic ecosystems. In lakes, metabolic rates are often diagnosed from die ...

In a paper published earlier this year, Finn Hirslund suggested to release degassed deepwater from methane harvesting to the surface layer of Lake Kiwi in order to counteract an observed slow rising of the chemoclines in the lake. In this comment, we prese ...

Lake Geneva is recovering from its eutrophic past but no significant trend in the areal hypolimnetic oxygen depletion rate has been observed over the last 30 years. Due to the large depth of 309 m, the lake is not mixed completely every winter which can le ...

The extent of littoral influence on lake gas dynamics remains debated in the aquatic science community due to the lack of direct quantification of lateral gas transport. The prevalent assumption of diffusive horizontal transport in gas budgets fails to exp ...

We report novel results of a numerical experiment designed for examining the basin-scale hydrodynamics that control the mass, momentum, and energy distribution in a daily wind-forced, small thermally-stratified basin. For this purpose, the 3-D Boussinesq e ...

Remote sensing helps foster our understanding of inland water processes allowing a synoptic view of water quality parameters. In the context of global monitoring of inland waters, we demonstrate the benefit of combining in-situ water analysis, hydrodynamic ...

Numerical simulations were carried out to investigate gyres within open lacustrine embayments subjected to parallel-to-shore currents. In such embayments, gyre formation occurs due to flow separation at the embayment’s upstream edge. High momentum fluid fr ...

In this study we compare turbulence parameters from field observations and model simulations specifically under the influence of weak to moderate wind forcing and breaking short waves. The experiment was performed during 12 days under very weak stratificat ...

During the past century, the construction of hydropower dams in the watershed of Lake Brienz has significantly altered the dynamics of turbidity, which has important implications for lake productivity. To assess these effects, we measured in situ carbon as ...

Lake Nyos, a deep crater lake, located in the north-west of Cameroon, was permanently stratified below 50 m depth due to subaquatic sources supplying warm, salty and CO2- enriched water into the deepest reaches. The high CO2 content in these source waters ...

Microscopic organisms in aquatic environments are continuously exposed to a variety of physical and chemical conditions. Traditionally, it is accepted that due to their small size the physiology of microscopic organisms is not affected by the moving fluid ...

The use of spaceborne medium resolution imaging spectrometers with neural network algorithms has proven a large potential for application with optically complex inland waters. We make use of this approach to investigate the bio-physical dynamics in a eutro ...

Alfred Johny Wüest

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Oxygen depletion in stratified lakes - why shallow and deep lakes react differently

Simulations of a double-diffusive interface in the diffusive convection regime

Present and past bio-available phosphorus budget in the ultra-oligotrophic Lake Brienz

A new robust oxygen-temperature sensor for aquatic eddy covariance measurements

Shear-induced convective mixing in bottom boundary layers on slopes

Measurements of eddy correlation oxygen fluxes in shallow freshwaters: Towards routine applications and analysis

Trend-oriented sampling strategy and estimation of soluble reactive phosphorus loads in streams

Data assimilation of in situ and satellite remote sensing data to 3D hydrodynamic lake models: a case study using Delft3D-FLOW v4.03 and OpenDA v2.4

Primary and Net Ecosystem Production in a Large Lake Diagnosed From High-Resolution Oxygen Measurements

Comment on An additional challenge of Lake Kivu in Central Africa - upward movement of the chemoclines by Finn Hirslund

Impact of deepwater mixing on hypoxia in Lake Geneva

Lake surface cooling drives littoral-pelagic exchange of dissolved gases

Hydrodynamics of a periodically wind‑forced small and narrow stratified basin: a large‑eddy simulation experiment

Resolving biogeochemical processes in lakes using remote sensing

Gyre formation in open and deep lacustrine embayments: The example of Lake Geneva, Switzerland

Measurement and simulation of viscous dissipation in the wave affected surface layer

Effects of alpine hydropower operations on primary production in a downstream lake

The entire lifetime of a distinct double‑diffusive staircase in crater Lake Nyos, Cameroon

Do Microscopic Organisms Feel Turbulent Flows?

MERIS observations of phytoplankton blooms in a stratified eutrophic lake