Adrien Mestrot is Assistant Professor Tenure-Track for Soil Science at the Institute of Geography of the University of Bern (Switzerland). He graduated from the Université de Pau et des Pays de l’Adour (UPPA, France) and obtained his Ph.D. from the University of Aberdeen (UK) in 2011. He then worked with the Soil Science Group at the University of Bern where he received a Marie Curie IEF Fellowship in 2013 and a SNSF Professorship in 2016.
Read Adrien Mestrot’s Emerging Investigator Series article “Mercury mobility and methylmercury formation in a contaminated agricultural flood plain: Influence of flooding and manure addition” and read more about him in the interview below:
Your recent Emerging Investigator Series paper focuses on Mercury mobility and methylmercury formation in a contaminated agricultural flood plain: Influence of flooding and manure addition. How has your research evolved from your first article to this most recent article?
During my PhD at the University of Aberdeen, I studied the biovolatilisation of arsenic from soil and my first paper described a new method to trap, identify and quantify volatile arsenic species. Biovolatilisation and biomethylation of arsenic are intrinsically linked and these two mechanisms are still not well understood. Having gained knowledge on speciation analysis and arsenic transformations in soils, I set out to explore the fate of other trace elements that are redox sensitive and undergo biomethylation and biovolatilisation in soils. I was particularly interested in antimony and mercury. I continued with this line of research as a Marie Sklodowska Curie fellow at the Institute of Geography of the University of Bern, where I could take full advantage of the state-of-the-art laboratory. During this time, I modified, developed and validated extraction and analytical techniques to measure volatile and dissolved forms of these three toxic elements in soils, soil solution and the atmosphere. After the fellowship, I obtained a SNSF Professorship and I more recently became Assistant Professor tenure-track for Soil Science – all in the same institute. I am now able to use these extraction and analysis techniques to understand the drivers behind the formation of these chemical species, while focusing on the effect of climate change (flooding, temperature) and agricultural practices (manure amendments) on the release, biomethylation and biovolatilisation of mercury, antimony and arsenic in soils.
What aspect of your work are you most excited about at the moment?
What currently excites me a lot as a new faculty member is the opportunities that are given to me to talk about the research conducted in my group. I assume people hear that a new person has been appointed and are curious to know more. During the last couple of years I have received several invitations to give talks in other research groups and Federal Offices in Switzerland. This is a great chance for me to tell the bigger story behind the various current projects and provides opportunities for building a diverse professional network in Switzerland.
In your opinion, what are the most important questions to be asked/answered in this field of research?
Generally, soils are seen as sinks for trace elements since these can bind to different soil components such as e.g. iron and manganese (oxy-)hydroxides, clays or organic matter. However, when flooding occurs, trace elements bound to iron and manganese (oxy-)hydroxides are released through a mechanism called reductive dissolution. Once released to the soil solution, the trace elements are available to soil organisms and plants and could be transported to groundwater. Microorganisms can also then take-up these elements and transform them to more toxic (e.g. methylmercury), more mobile or even volatile species. Current global climate predictions tell us that extreme weather events with heavy rains and flooding will become more frequent, thus turning soils into a potential source of trace elements. Therefore, for me, the most important question is about the potential influence of climate change on the release and the speciation of trace elements in soils and if it can influence their global biogeochemical cycle.
What do you find most challenging about your research?
In order to understand and characterise the release, biomethylation and biovolatilisation of trace elements in soils, one must have a very broad set of skills. From soil science to advanced analytical chemistry and a sound understanding of microbial processes. However, this means that collaborations are necessary which is always interesting and an opportunity to extend one’s research horizon.
In which upcoming conferences or events may our readers meet you?
I try to attend as few conferences as necessary, both for family reasons (I have a young son) and to reduce my carbon footprint. I tend to favour conferences that are local or can be reached by train although this is not always possible! Every year I attend the Swiss Geoscience Meeting and every two years there is ICOBTE. Of course I try to go to Goldschmidt as often as possible since it is an important conference in my field. This year I will attend ContaSed, which we are organising in Bern, and Eurosoil, which will be taking place in August 2020 in Geneva.
How do you spend your spare time?
I like gardening and DIY. These are activities that allow me to focus for a few hours on an object or task through a well-defined activity with a start and an end, which is very different from our day-to-day work as scientists. I also love hiking, climbing and spending time with my family and friends.
Which profession would you choose if you were not a scientist?
I would choose to be a science journalist, a science communicator or a managing editor for a journal. I don’t think I would enjoy working in a non-science related job.
Can you share one piece of career-related advice or wisdom with other early career scientists?
My advice for early career researchers is to take part in the different commissions of your institution and become a representative for your peers (e.g. PhD or postdoc representative). It will allow you to network with more senior members of your institutions (lecturers, professors etc..) while contributing to shape your place of work and potentially your university and beyond. In my opinion, the most pressing issues to be addressed in research include improving gender equality, work-life balance and sustainability. I think that early career researchers and newly appointed faculty members have strong leverage to push forward the required changes in academia.
