Judith Braun

        Head and shoulder image of PhD researcher Judith Braun

PhD student

I am interested in the biogeochemical cycling of nitrogen in the Arctic Ocean, one of the most rapidly changing ecosystems on the planet. In my project, I study the impact of receding sea ice and changes in ocean mixing on inorganic and organic nutrient supply, uptake, and circulation in the Barents Sea over an entire season. To do this, I use various approaches to measure nutrient concentrations as well as uptake rates of different nitrogen compounds with implications for the distribution and magnitude of primary production in the changing Arctic Ocean.

Contact details:
  • judith.braun@sams.ac.uk

This PhD is embedded within the Arctic PRIZE project and examines the uptake and cycling of different forms of nitrogen (N) by different phytoplankton groups using techniques such as mass spectrometry.

The recent decline of Arctic sea ice is one of the most pronounced examples of contemporary physical climate change on Earth. The Arctic PRIZE project aims to determine how these sea ice changes will affect biological and biogeochemical systems in this climatically sensitive region. Nitrogen availability is a principal determinant of phytoplankton community composition and abundance.



Professor Keith Davidson, SAMS

Dr Sian Henley, University of Edinburgh



Natural Environment Research Council



University of the Highlands and Islands

Peer-reviewed publications

Henley SF, Porter M, Hobbs L, Braun J, Guillaume-Castel R, Venables EJ, Dumont J, Cottier F (2020) Nitrate supply and uptake in the Atlantic Arctic sea ice zone:seasonal cycle, mechanisms and drivers. Philosophical Transactions of the Royal Society A 378: 20190361. https://dx.doi.org/10.1098/rsta.2019.0361 

Judith Braun, Maria Mooshammer, Wolfgang Wanek, Judith Prommer, Tom W N. Walker, Tobias Rütting, Andreas Richter (2018) Full 15N tracer accounting to revisit major assumptions of 15N isotope pool dilution approaches for gross nitrogen mineralization. Soil Biology and Biochemistry, 117, 16-26

Eugenio Díaz-Pines, Saúl Molina-Herrera, Michael Dannenmann, Judith Braun, Edwin Haas, Georg Willibald, Cristina Arias-Navarro, Rüdiger Grote, Benjamin Wolf, Gustavo Saiz, Cisco Aust, Jörg-Peter Schnitzler and Klaus Butterbach-Bahl (2016) Nitrate leaching and soil nitrous oxide emissions diminish with time in a hybrid poplar short-rotation coppice in southern Germany. GCB Bioenergy, 9, 613-626


Poster presentations

University of the Highlands and Islands Research Student Conference 2017

Teaching experience

Seminar and Exercise on Stable Isotopes in Ecology - Stable Isotope Tracing (Master level), University of Vienna, Austria
Tutoring: Field course in functional ecology (Bachelor level)

Tutoring: Ecosystem and Biogeochemistry Laboratory: Techniques in Terrestrial Ecosystem Ecology (Bachelor level)

Fieldwork experience

January: Polar night cruise (water sampling and stable isotope uptake experiments), Barents Sea, NO
April/May: Spring cruise (water sampling and stable isotope uptake experiments), Barents Sea, NO
June/July: Summer cruise (water sampling and stable isotope uptake experiments), Barents Sea, NO

2014 – 2015
Performance of fieldwork (soil sampling and performance of isotope tracer experiments) and laboratory work at the SILVER facility for Isotope Ratio Mass Spectrometry at the University of Vienna, Austria

2011 – 2012
Fieldwork (gas sampling, soil sampling, performance of isotope tracer experiments) and laboratory work within the KiLi project framework, Tanzania

Public engagement experience

Polar science outreach events as part of the Edinburgh International Science Festival, UK

Employment history

2015-16 Student Assistant. University of Vienna (Austria)

2011-12 Research Assistant. IMK-IFU (Germany)



2016 MSc Environmental Sciences. University of Vienna (Austria)

2012 BSc Biology. University of Innsbruck (Austria)