News

22.04.2025

Visit to the Federal Office for Metrology

The Swiss Federal Institute of Metrology METAS is the federal competence center for all matters relating to measurement, measuring instruments and measuring procedures. It is the national metrology institute of Switzerland. As such, its mission is to ensure that measurements can be made in Switzerland with the accuracy required for the needs of industry, research and administration. METAS covers a wide range of specialist areas, it is also the Reference Laboratory for Chemical Elements and Nitrogen Compounds in Foodstuffs which directly relates to our research. It is important for us to see and understand what we rely on in our daily work: accurate measuring instruments and reliable constants.

10.04.2025

New article published: Mercury Accumulation and Biomagnification in the Barn Owl (Tyto alba) Food Chain

Mercury (Hg) accumulation and biomagnification in the barn owl (Tyto alba) food chain were studied across three trophic levels: soil and moss, small mammal fur from pellets, and barn owl feathers. Spatial analysis showed regional Hg variation, with the highest concentrations in feathers (170 μg/kg) and fur (150 μg/kg), followed by soil (63 μg/kg). Bioaccumulation and biomagnification factors indicated increasing Hg through the food chain. Methylmercury made up most Hg in feathers. Diet strongly influenced Hg levels, with omnivorous prey causing higher fur concentrations than herbivorous prey. Results underscore the role of diet in mercury exposure and its use in ecological monitoring.

Link to paper (PDF, 1.2 MB)

04.04.2025

New article released: Pesticide contamination in indoor home dust: A pilot study of non-occupational exposure in Argentina

Pesticide use is increasing globally, and Argentina ranks fifth. This study examined indoor dust from 48 urban homes in Argentina’s Pampas Region, detecting 41 of 49 targeted pesticides, including banned substances and agricultural-only chemicals like glyphosate and atrazine. Some residues exceeded 1,000 μg/kg, and up to 32 compounds were found per sample. Despite being non-agricultural homes, contamination was linked to behaviors like wearing shoes indoors, pet ownership, flea treatments, and indirect occupational exposure. Results highlight the widespread presence of pesticides in residential environments and underscore the need for better monitoring and research on long-term exposure and health risks.

Link to paper (PDF, 1.5 MB)

03.04.2025

New paper published: ORDNA: Deep-learning-based ordination for raw environmental DNA samples

Environmental DNA (eDNA) metabarcoding aids biodiversity monitoring but poses challenges for traditional data analysis. ORDNA (ORDination via Deep Neural Algorithm) is presented, a deep learning method that directly processes raw eDNA sequences, avoiding biased bioinformatic steps. Using contrastive self-supervised learning (triplet loss), ORDNA generates two-dimensional representations of eDNA samples based on read composition. Applied to four diverse datasets, ORDNA outperformed conventional ordination methods in visualizing ecological patterns. This highlights the power of deep learning in eDNA analysis, offering a more accurate, efficient approach to understanding biodiversity and ecosystem health through non-invasive sampling techniques.

Link to paper (PDF, 1.7 MB)

19.02.25

New Colloquium Program!

The Colloquium will take place on Tuesdays from February 19th to May 30th from 16h15 to 18h00. Interested people are welcome to attend in person in room 116 of the Uni Mittelstrasse (Mittelstrasse 43). For more information, please download the flyer. Looking forward to meeting you there!

Soil Science Colloquium Spring Semester 2025 (PDF, 377KB)

11.02.2025

Congratulations Luzia!

On Tuesday, 11.02.2025, Luzia successfully defended her MSc thesis entitled "Impacts of war– Contamination of soils in Ukraine in and around craters with potentially toxic trace elements". Congratulations from the Soil Science group, dear Luzia, and all the best for your future endeavours!

16.01.2025

Congratulations Sinh!

On January 16th, Sinh successfully defended his master's thesis entitled "A lysimeter field experiment to investigate microplastic transport through preferential flow paths in agricultural soils in Switzerland.". Congratulations Sinh and all the best for your future endeavours!

29.11.2024

New article published: Shift of the ecosystem nitrogen cycle from open to closed within a century along a glacial retreat chronosequence at Mount Gongga, southwest China

This study investigates the shift in the nitrogen (N) cycle during primary succession along a glacial retreat chronosequence at Mount Gongga, southwest China. By assessing biological nitrogen fixation, ammonification rates, and nitrogen retention through 15N tracer experiments, the research tracks how nitrogen cycling evolves from open to closed over a century. The findings show that nitrogen accumulation increases rapidly, and over time, the ecosystem shifts toward tighter N cycling, with minimal nitrification in older stages of succession, reflecting a mature system.

Link to paper (PDF, 1.6 MB)

17.11.2024

New article published: Perspectives on using peat records to reconstruct past atmospheric Hg levels

This article examines the potential of peatlands as valuable archives for reconstructing past atmospheric mercury (Hg) levels. As human activities have significantly increased Hg emissions, understanding regional variations in pollution is crucial. Peatlands, with their preserved records, can provide insights into past Hg cycling. This perspective highlights the role of peat vegetation and productivity in Hg sequestration and offers recommendations for improving the use of peat cores to track Hg levels over time, aiding global Hg cycle studies and evaluating mitigation efforts.

Link to paper (PDF, 1.9 MB)

30.10.2024

New article on methodology released: All black: a microplastic extraction combined with colour-based analysis allows identifcation and characterisation of tire wear particles (TWP) in soils

Tire wear particles (TWP) are a major source of microplastics in the environment, yet reliable data on their concentration and characteristics remain scarce. This article presents a novel method for extracting and identifying TWPs from soil, combining color-based analysis with machine learning to distinguish them from other black particles like charcoal. The approach offers high recovery rates and accurate results, allowing for detailed studies of TWP concentrations in highway-adjacent soils, with potential applications in addressing knowledge gaps in environmental microplastic research.

Link to paper (PDF, 1.6 MB)

28.10.2024

New paper published: Marine and terrestrial contributions to atmospheric deposition fluxes of methylated arsenic species

A new study explores the atmospheric deposition of methylated arsenic species, a toxic element from both natural and anthropogenic sources. The research, conducted at the Pic du Midi Observatory in France, reveals significant levels of methylated arsenic in precipitation, cloud water, and aerosols under free tropospheric conditions, indicating long-range transport. By identifying terrestrial and marine sources, the study highlights the importance of atmospheric deposition as a potentially overlooked contributor to bioavailable methylated arsenic in soils, impacting plant uptake and environmental health.

Link to paper (PDF, 1.6 MB)

19.09.24

New Colloquium Program!

The Colloquium will take place on Tuesdays from September 17th to December 17th from 16h15 to 18h00. Interested people are welcome to attend in person in room 002 of the GIUB (Hallerstrasse 12). For more information, please download the flyer. Looking forward to meeting you there!

Soil Science Colloquium Fall Semester 2024 (PDF, 270KB)

11.09.2024

Congratulations Timon!

Last Tuesday, 10.09.2024, Timon successfully defended his MSc thesis entitled "Evaluation of soil composting as a possible method for the bioremediation of soils contaminated with explosives". Congratulations from the Soil Science group, dear Timon, and all the best for your future endeavors!

11.09.2024

Congratulations Samuel!

Last Friday, 06.09.2024, Samuel successfully defended his MSc thesis entitled "Identifying innovative agricultural practices to reduce the reliance on plant protection products (PPP) – a systematic review". Dear Samuel, congratulations from the Soil Science group and all the best for your future endeavors!

11.09.2024

Congratulations Ariane!

Last Thursday, 05.09.2024, Ariane successfully defended her MSc thesis entitled "Approaching the multi-hazard of contaminated sites at risk of landslides and floods in Switzerland". Congratulations from the Soil Science group, dear Ariane, and all the best for your future endeavors!

10.09.2024

New paper published: Arsenic, selenium, and mercury speciation in hypersaline lakes of the Andean Altiplano: Link between extreme levels and biodiversity repartition

This study investigated the concentrations and chemical forms (speciation) of As, Hg, and Se in sediment, water, and air samples of Lagunas in the South Lipez region (>4200 m a.s.l.) of southern Bolivian Altiplano, where there are ecological niches for endemic species. The concentrations and chemical forms were compared with the repartition of biodiversity (invertebrates, algae, and bacteria). The drastic disparity between As, Se and Hg concentrations and speciation between lakes has important implications for their cycling in these extreme aquatic systems. Finally, the salinity, including major ions, and high levels of As were among the main drivers of biodiversity repartition between lakes. These findings underscore the complex biogeochemistry in these high-altitude environments. For further information please click on the link below.

10.09.2024

Open PhD position in Analytical Chemistry / Environmental Biogeochemistry

The Laboratory for Inorganic Analysis and References from the Swiss Federal Institute of Metrology (METAS) and the Soil Science Group, Institute of Geography, University of Bern invite applications for a Ph.D. position in Analytical Chemistry/Environmental Biogeochemistry with the objectives to develop methods for the characterization of Hg nanoparticles and to study their fate in soils and sediments. Questions regarding the position or the application process can be addressed to Dr. Sylvain Bouchet (Sylvain.Bouchet@metas.ch) and/or Prof. Dr. Adrien Mestrot (adrien.mestrot@unibe.ch). If interested please send your application (CV, motivation letter of 1 page max, and the names of at least two references) before October 31st by email to: hire.giub@gmail.com. The preferred starting date is January 2025 but this call will remain open until the position is filled. For more information, please have a look at the PDF below.

PhD position in Analytical Chemistry/Environmental Biogeochemistry (PDF, 285KB)

10.08.2024

New article published: Pesticide residues in European sediments: A significant concern for the aquatic systems?

A new study investigates pesticide contamination in waterbed sediments across 38 water bodies in Europe, primarily in agricultural regions. The research reveals widespread pesticide residues, with 99 different chemicals detected, including non-approved pesticides. Glyphosate, AMPA, and DDT were the most common. The study highlights significant regional variation in contamination levels, with some areas, like the Czech Republic, showing the highest concentrations. The findings stress the importance of monitoring pesticide levels in sediments to assess long-term environmental risks and guide future policy and mitigation efforts.

Link to paper (PDF, 2.8 MB)

22.07.2024

Congratulations Ladina!

Last Wednesday, 17.07.2024, Ladina successfully defended her MSc thesis entitled "Trace element concentration in organ and muscle tissue of grey wolves (Canis lupus) and Eurasian lynx (Lynx lynx) in Switzerland". Congratulations from the Soil Science group, dear Ladina, and all the best for your future endeavours!

22.07.2024

New paper from Hang has been published

Hang's new paper entitled "Soil Indigenous Microbes Interact with Maize Plants in High-Arsenic Soils to Limit the Translocation of Inorganic Arsenic Species to Maize Upper Tissues" has been published - congratulations Hang! In this study, they performed a greenhouse pot experiment with maize plants grown at different soil As levels to study the role of soil microbes on uptake of different As species by maize. Compared to uncontaminated soils, maize in high-As soils tended to accumulate more As in stems and less in leaves and grains, proportionally. Arsenic levels in stems were increased in sterilized soils due to the disturbance of the microbiome. The sterilization effects caused a phosphorus and manganese deficiency, leading to a higher As uptake in plants, that increased with rising As levels and resulted in a lower total dry biomass of the plants. In summary, this study highlights the role of soil indigenous microbes in limiting the uptake and translocation of inorganic As into maize. The paper is availabel under the link below.

28.06.2024

Congratulations Noël!

On June 13th, Noël successfully defended his master's thesis on the topic of «Dynamic Evolution of Hg Methylation in a Polluted Agricultural Floodplain». Congratulations Noël, the Soil Science Group wishes you all the best for your future endeavours!

14.06.2024

Welcome Thomas Wassermann!

Thomas Wassermann has started his PhD in the Soil Science group under the supervision of Dr. Markus Steffens and in collaboration with the Research Institutes of Organic Agriculture FiBL. Thomas completed his Bachelor's degree in Agricultural Sciences at the University of Natural Resources and Life Sciences (BOKU) in Vienna, followed by two degree programmes in Agricultural and Food Economics (Dipl.-Ing.) and in Crop Science (Dipl.-Ing.), also at the BOKU in Vienna. In his PhD project, Thomas will focus on soil health and its monitoring using infrared spectroscopy. The aim is to gain potential for measurement, reporting and verification systems and to derive ecosystem services / soil functions. In the course of this project, Thomas will fulfil a spectroscopy task in two EU Horizon projects: InBestSoil and BioServicES.

06.06.2024

Can Effective Microorganisms Influence Green-Manure Decomposition?

A collaborative study by Agroscope, FiBL and the University of Bern has been published at Agrarforschung Schweiz (Swiss Agricultural Research). Although effective microorganisms (EM) are frequently used to shallowly incorporate green manures (cover crops) in the field, almost no scientific research has been conducted on them to date. This study simulated the decomposition of green manures with EM in the laboratory.

17.05.2024

New MSc thesis topic: "Potentially Toxic Trace Elements (PTTEs) profiles in the varved sediments of the Faulenseemoos"

We propose a collaborative Master thesis project between the groups of Prof. Willy Tinner (Paleoecology, IPS) and of Prof. Adrien Mestrot (Soil Science, GIUB) on the topic of "Potentially Toxic Trace Elements (PTTEs) profiles in the varved sediments of Faulenseemoos". Faulenseemoos, a bog in the Bernese Oberland, provides with its seasonally layered deposits a natural archive. Preserved in these varves are proxies such as pollen, diatoms and insect remains, as well as elements and stable isotopes that provide information about the history of vegetation, plants, animals, water quality, temperatures, precipitation, and intensity and type of agriculture practiced by our ancestors. Using PTTEs (commonly known as heavy metals) as proxies, one can also retrace the economic development and pollution history of a catchment. For more information on this MSc thesis topic, please download the flyer.

MSc thesis Faulenseemoos (PDF, 79KB)

07.05.2024

Group event at the Engehalbinsel

On May 1st, the Soil Science group had a group event at the Engehalbinsel to clean and restore the six soil profiles. These profiles are representatives of Swiss soils and are used by different educational institutions to teach the formation of soils. A website (Berner Böden) providing further information on the six soil profiles, their formation and properties will soon be available. The fun group event was rounded off with dinner at the restaurant Zehendermätteli im Glück. Thank you to everyone who came to help!

02.05.2024

Guest speaker 07.05.2024

In our next colloquium (Tuesday, 07.05. at 16h15 in Mittelstrasse 43, Seminarraum 234), Dr. Matthias Wiggenhauser, "Oberassistent" in the Group of Plant Nutrition at the Insitute of Agricultural Sciences, ETH Zurich, will give a talk entitled "Leveraging Isotope Tools to Determine the Fate of Trace Metals in Agroecosystem". He will present how novel isotope tools can be used to precisely quantify fluxes of trace metals and to identify the underlaying biogeochemical processes that control these pathwas along the soil-crop-human continuum. For more information, please dowload the flyer.

Guest speaker 07.05.2024 (PDF, 884KB)

 

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