HS Hydrological Sciences
The 2019 Outstanding Student Poster and PICO (OSPP) Award is awarded to Morgane Merlin for the poster/PICO entitled:
Separating transpiration and stem water storage in a large boreal tree using Heat Ratio Method sap flow sensors (Merlin, M.; Solarik, K.; Landhäusser, S.)
Click here to download the poster/PICO file.
Morgane Merlin is a PhD candidate from the Renewable Resources department of the Faculty of Agricultural, Life and Environmental Sciences at the University of Alberta, Edmonton, Canada. Her research focuses on understanding the temporal and spatial dynamics of water uptake in boreal forest tree species, and its relationship with climate and reclamation practices using heat ratio method (HRM) sap flow sensors. The poster presented at EGU 2019 (Evapotranspiration: in-situ measurements and the upscaling challenge – HS10.4) showed results of the validation of the accuracy of the HRM sap flow sensors on a large mature boreal aspen tree, and insights into the relationship between sap flow and water storage along the stem. The HRM sap flow sensors were shown to provide reliable estimates of total tree water uptake when appropriately corrected for zero-flow conditions and properly extrapolated over the whole sapwood area. Using the sap flow sensors, we show that this large aspen tree relied daily on stored water within the stem to support early morning canopy photosynthesis. Appropriate use of the HRM sap flow sensors in large trees should shed some light on the potentially crucial role of this stem water reservoir under normal conditions and in the resistance and resilience of boreal trees to drought stress.