At an excursion during my master studies in Ecology and Biodiversity at the University of Innsbruck, I was introduced to the Vjosa River and its tributaries in Greece and Albania. The Vjosa—now recognized as Europe’s first Wild River National Park— has an incredibly diverse catchment and features several braided sections at the downstream part. I still remember the moment when I encountered one of these braided sections for the first time, on the Sarantaporos River, one of the main tributaries of the Vjosa. I was immediately fascinated by the wide, open morphology and the complexity of the landscape. The sheer lateral extent of the river, combined with the heterogeneity of the constantly changing channels and gravel bars, was unlike any river I had seen before.
During the same excursion, I was introduced to what greenhouse gases have to do with rivers. Until then, I had not considered the significant role rivers have in the carbon cycle. The idea that rivers produce and release greenhouse gases (like methane and carbon dioxide) sparked my curiosity. This fascination led me to focus my master thesis on methane concentrations in the hyporheic zones of the Vjosa’s braided sections. Concrete was my master thesis about methane concentrations in the hyporheic of braided river sections of the Vjosa. The hyporheic zone—the sediment body between the surface water and the groundwater—is mostly water-saturated and low in oxygen, making it an ideal environment for methane production. This is because methane needs anoxic conditions to be potentially produced, making the hyporheic an ideal environment. Through my research, I discovered some interesting patterns that only deepened my interest and fascination. I realized how little is still known about the role of braided rivers in the global carbon cycle and the questions only got more.
Now, I am continuing this path by doing a PhD on the same topic, but expanding my perspective. The title of my PhD is “Carbon cycling in braided rivers – carbon dioxide and methane emissions across a dynamic aquatic-terrestrial habitat mosaic”. The goal is to improve the understanding of the emissions of carbon dioxide and methane of braided rivers, focusing on the magnitude of these emissions and how these gases are mediated across various habitat types. I am particularly interested in the role of flow fluctuations – drying and wetting cycles - which continually reshape the landscape and thus influence where and how gases are produced and emitted. In addition to ongoing work on the Vjosa, I am expanding my research to include the Lech River, where some of the last remaining braided river stretches in Austria can be found.
My PhD project aims to better understand the net emissions of carbon dioxide and methane from braided rivers, with a focus on how these gases are mediated across different habitat types. This will address major knowledge gaps of river carbon cycling and its implications for the global carbon cycle. My work is driven by scientific inquiry and a passion for understanding and protecting these dynamic river systems.
Barbara JECHSMAYR
Research Group: Fluvial Ecosystem Ecology