Publications by Alfred Johny Wüest

Related publications (118)

Internal carbon and nutrient cycling in Lake Baikal: sedimentation, upwelling, and early diagenesis

The internal cycles of carbon, silica, nitrogen, and phosphorus in the South and North Basins of Lake Baikal were quantified in the frame of a multidisciplinary collaboration. Fluxes of particulate organic matter from the epilimnion to the deep water were ...

Elsevier2005

Impact of a large tropical reservoir on riverine transport of sediment, carbon, and nutrients to downstream wetlands

Alfred Johny Wüest

Large dams can have major ecological and biogeochemical impacts on downstream ecosystems such as wetlands and riparian habitats. We examined sediment removal and carbon (C), nitrogen (N), and phosphorus (P) cycling in Itezhi-Tezhi Reservoir (ITT; area = 36 ...

Amer Geophysical Union2011

Disentangling the effects of climate change and reoligotrophication on primary production in a large lake

Alfred Johny Wüest, Hugo Nicolás Ulloa Sánchez, Shubham Krishna

Climate change and reduction in nutrient loads have significant effects on primary production and phytoplankton growth dynamics. Since in the last few decades in many regions, nutrients in lakes were reduced simultaneously as the climate changed. Yet, it r ...

SPRINGER BASEL AG2023

Evolution of stream and lake water temperature under climate change

Alfred Johny Wüest, Damien Bouffard, Bettina Schaefli, Wolf Hendrik Huwald, Adrien Michel, Carl Love Mikael Råman Vinnå

This report presents past observations and projects the future development of water temperature in Swiss lakes and rivers. Projections are made until the end of the 21st century using the CH2018 climate scenarios. Besides climate change effects on temperat ...

Federal Office for the Environment (FOEN)2021

Physical effects of thermal pollution in lakes

Alfred Johny Wüest, Damien Bouffard

Anthropogenic heat emissions into inland waters influence water temperature and affect stratification, heat and nutrient fluxes, deep water renewal, and biota. Given the increased thermal stress on these systems by growing cooling demands of riparian/coast ...

American Geophysical Union2017

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

Sensitivity of ancient Lake Ohrid to local anthropogenic impacts and global warming

Alfred Johny Wüest

Human impacts on the few ancient lakes of the world must be assessed, as any change can lead to an irreversible loss of endemic communities. In such an assessment, the sensitivity of Lake Ohrid (Macedonia/Albania; surface area A = 358 km(2), volume V = 55 ...

Int Assoc Great Lakes Res2006

Oxygen consumption in seasonally stratified lakes decreases only below a marginal phosphorus threshold

Alfred Johny Wüest, Robert Vincent Schwefel

Areal oxygen (O-2) consumption in deeper layers of stratified lakes and reservoirs depends on the amount of settling organic matter. As phosphorus (P) limits primary production in most lakes, protective and remediation efforts often seek to reduce P input. ...

Springer Nature2019

Carbonate sedimentation and effects of eutrophication observed at the Kalista subaquatic springs in Lake Ohrid (Macedonia)

Alfred Johny Wüest, Marco Matter

To date, little is known about the role of spring waters with respect to authigenic carbonate precipitation in a shallow lacustrine setting. Lake Ohrid, located in Southeastern Europe, is a large lake fed to over 50% by karstic springs of which half enter ...

Copernicus Gesellschaft Mbh2010

Sediment accumulation and carbon, nitrogen, and phosphorus deposition in the large tropical reservoir Lake Kariba (Zambia/Zimbabwe)

Alfred Johny Wüest

Large dams affect the aquatic continuum from land to ocean by accumulating particles and nutrients in their reservoirs. We examined sediment cores to quantify sediment, organic carbon (OC), nitrogen (N), and phosphorous (P) accumulation, and to examine his ...

Amer Geophysical Union2011

Balancing nutrient inputs to Lake Kivu

Alfred Johny Wüest, Natacha Pasche, Beat Mueller

The primary production in meromictic Lake Kivu is sustained by external nutrient inputs and by internal loading due to upwelling caused by sub-aquatic sources. We present here the results of external loading of phosphorus (P), nitrogen (N) and silica (Si) ...

Elsevier Sci Ltd2009

Seasonality modulates wind-driven mixing pathways in a large lake

Alfred Johny Wüest, Hugo Nicolás Ulloa Sánchez, Oscar Rodrigo Sepúlveda Steiner, Bieito Fernandez Castro, Sebastiano Piccolroaz, Sébastien Manuel Lavanchy

Turbulent mixing controls the vertical transfer of heat, gases and nutrients in stratified water bodies, shaping their response to environmental forcing. Nevertheless, due to technical limitations, the redistribution of wind-derived energy fuelling turbule ...

SPRINGERNATURE2021

Spatial Variability of Turbulent Mixing From an Underwater Glider in a Large, Deep, Stratified Lake

Alfred Johny Wüest, Damien Bouffard, Sébastien Lavanchy, Oscar Rodrigo Sepúlveda Steiner, Bieito Fernandez Castro, Sébastien Manuel Lavanchy

Recent efforts using microstructure turbulence measurements have contributed to our understanding of the overall energy budget in lakes and linkages to vertical fluxes. A paucity of lake-wide turbulence measurements hinders our ability to assess how repres ...

AMER GEOPHYSICAL UNION2023

Subaquatic slope instabilities: The aftermath of river correction and artificial dumps in Lake Biel (Switzerland)

Alfred Johny Wüest, Carl Love Mikael Råman Vinnå

River engineering projects are developing rapidly across the globe, drastically modifying water courses and sediment transfer. Investigation of the impact of engineering works focuses usually on short-term impacts, thus a longer-term perspective is still m ...

2020

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

Energetics of Radiatively Heated Ice-Covered Lakes

Alfred Johny Wüest, Damien Bouffard, Hugo Nicolás Ulloa Sánchez

We derive the mechanical energy budget for shallow, ice-covered lakes energized by penetrative solar radiation. Radiation increases the available and background components of the potential energy at different rates. Available potential energy drives under- ...

2019

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

The Imprint of Primary Production on High-Frequency Profiles of Lake Optical Properties

Alfred Johny Wüest, Camille Roland Marie Minaudo, Sébastien Manuel Lavanchy

Water inherent optical properties (IOPs) contain integrative information on the optical constituents of surface waters. In lakes, IOP measurements have not been traditionally collected. This study describes how high-frequency IOP profiles can be used to do ...

AMER CHEMICAL SOC2021

Inhibited vertical mixing and seasonal persistence of a thin cyanobacterial layer in a stratified lake

Alfred Johny Wüest, Damien Bouffard, Oscar Rodrigo Sepúlveda Steiner, Bieito Fernandez Castro

Harmful blooms of the filamentous cyanobacteria Planktothrix rubescens have become common in many lakes as they have recovered from eutrophication over the last decades. These cyanobacteria, capable of regulating their vertical position, often flourish at ...

2021

Double-diffusive convection in Lake Kivu

Alfred Johny Wüest

Double-diffusive staircases with a total of 230-350 mixed layers and sharp interfaces were observed in nine microstructure temperature profiles measured during February 2004 in Lake Kivu. The presence of these staircases at depths. 120 m indicates that dia ...

American Society of Limnology and Oceanography2010