Publications by Natacha Tofield-Pasche

An innovation of two established methods for monitoring water colour and clarity: participatory science using the mini- and midi- secchi disks

Measurements of water colour and clarity are used to track the environmental status of lakes, estuaries and oceans. The oldest standardised methods for measuring water clarity and colour are the Secchi disk and Forel-Ule colour scale. Both techniques were ...

2025

Vertical distribution and seasonal dynamics of planktonic cyanobacteria communities in a water column of deep mesotrophic Lake Geneva

Natacha Tofield-Pasche, Stéphane Joost, Tamar Kohn, Charlotte Gisèle Weil, Oliver Michele Selmoni, Anna Carratala Ripolles, Coralie Chappelier, Hannah Elisa Chmiel, Annie Sandrine Guillaume

Background: Temperate subalpine lakes recovering from eutrophication in central Europe are experiencing harmful blooms due to the proliferation of Planktothrix rubescens, a potentially toxic cyanobacteria. To optimize the management of cyanobacteria blooms ...

Frontiers Media SA2023

Need for harmonized long-term multi-lake monitoring of African Great Lakes

Natacha Tofield-Pasche

To ensure the long-term sustainable use of African Great Lakes (AGL), and to better understand the func-tioning of these ecosystems, authorities, managers and scientists need regularly collected scientific data and information of key environmental indicato ...

Elsevier Sci Ltd2023

Current status and strategic way forward for long-term management of Lake Kivu (East Africa)

Natacha Tofield-Pasche, Alfred Johny Wüest

Lake Kivu is one of the African Great Lakes lying in the Albertine Rift. It provides livelihoods to 5.7 million people living in the two riparian countries of the Democratic Republic of the Congo and the Republic of Rwanda. Lake Kivu is currently experienc ...

Elsevier Sci Ltd2023

LeXPLORE: A floating laboratory on Lake Geneva offering unique lake research opportunities

Natacha Tofield-Pasche, Alfred Johny Wüest, Sébastien Lavanchy, Damien Bouffard

Environmental sciences depend heavily on observational data. Successful studies of ecological processes in lakes require in-situ data that cover the relevant temporal scales from milliseconds to entire seasons. Temporal and spatial coverage requirements re ...

2021

Where does the river end? Drivers of spatiotemporal variability in CO2 concentration and flux in the inflow area of a large boreal lake

Natacha Tofield-Pasche, Hannah Elisa Chmiel

River inflow affects the spatiotemporal variability of carbon dioxide (CO2) in the water column of lakes and may locally influence CO2 gas exchange with the atmosphere. However, spatiotemporal CO2 variability at river inflow sites is often unknown leaving ...

American Society of Limnology and Oceanography2020

Lateral variations and vertical structure of the microbial methane cycle in the sediment of Lake Onego (Russia)

Natacha Tofield-Pasche, Nathalie Dubois

The significance of methane production by lakes to the global production of greenhouse gas is well acknowledged while underlying processes sustaining the lacustrine methane budget remain largely unknown. We coupled biogeochemical data to functional and phy ...

2019

Implications of river intrusion and convective mixing on the spatial and temporal variability of under-ice CO2

Natacha Tofield-Pasche, Damien Bouffard

Ice-covered periods might significantly contribute to lake emissions at ice-melt, yet a comprehensive understanding of under-ice carbon dioxide (CO2) dynamics is still lacking. This study investigated the processes driving spatiotemporal patterns of under- ...

2019

Life under ice in Lake Onego (Russia) - an interdisciplinary winter limnology study

Natacha Tofield-Pasche, Alfred Johny Wüest

2019

Dissolved Organic Matter and Associated Trace Metal Dynamics from River to Lake, Under Ice-Covered and Ice-Free Conditions

Natacha Tofield-Pasche, Hannah Elisa Chmiel

The present study investigates the changes in dissolved organic matter (DOM) composition and its influences on trace metal dispersion from the Shuya River (SR) in the Petrozavodsk Bay of Lake Onega during ice covered and ice-free periods. Humic substances ...

2019

Ice-covered Lake Onega: effects of radiation on convection and internal waves

Natacha Tofield-Pasche, Alfred Johny Wüest, Damien Bouffard

Early-spring under-ice convection in the Petrozavodsk Bay of Lake Onega (Russia) was investigated as part of an interdisciplinary research project conducted during March 2015. Measurements performed using a thermistor chain and vertical profiling sensors w ...

Springer Verlag2016

Leman-Baikal: Remote sensing of lakes using an ultralight plane

Ulrich Lemmin, Bertrand Merminod, Natacha Tofield-Pasche, Damien Bouffard, Yosef Akhtman, Dragos Constantin, Martin Rehak, Vincent Maurice Nouchi, Galina Shinkareva

The Leman-Baikal project constitutes an international Swiss-Russian collaborative research initiative in the field of physical limnology. The three-year framework involves the development and deployment of a novel multispectral and hyperspectral remote sen ...

2014

Methane formation and future extraction in Lake Kivu

Natacha Tofield-Pasche, Alfred Johny Wüest, Martin Schmid

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

Nutrient cycling in Lake Kivu

Natacha Tofield-Pasche, Alfred Johny Wüest, Martin Schmid

This chapter summarizes the knowledge on mixing and transport processes in Lake Kivu. Seasonal mixing, which varies in intensity from year to year, influences the top ∼65 m. Below, the lake is permanently stratified, with density increasing stepwise from ∼ ...

Springer2012

Methane sources and sinks in Lake Kivu

Natacha Tofield-Pasche, Alfred Johny Wüest, Martin Schmid

Unique worldwide, Lake Kivu stores enormous amounts of CH4 and CO2. A recent study reported that CH4 concentrations in the lake have increased by up to 15% in the last 30 years and that accumulation at this rate could lead to catastrophic outgassing by sim ...

Amer Geophysical Union2011

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

Bernhard Wehrli, Natacha Tofield-Pasche, Alfred Johny Wüest, Beat Mueller, Martin Schmid

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

Balancing nutrient inputs to Lake Kivu

Natacha Tofield-Pasche, Alfred Johny Wüest, Beat Mueller, Martin Schmid

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