LIST WATER LECTURES Seminar Series 2018 #3

 

As part of the LIST Water Lectures series organised for the spring/ summer session 2018, the next event will take place on 15 May 2018 at LIST premises in Belvaux (LU).

Dr. Rolf Siegwolf from Paul Scherrer Institute, Villigen, and Swiss Federal Institute for Forest, Snow and Ledscape Research (CH), will be the invited speaker.

SEMINAR TOPIC: THE RELEVANCE OF STABLE ISOTOPES IN PRECIPITATION NAD SOIL WATER FOR PLANT AND ECO-PHYSIOLOGICAL RESEARCH

The variation of the stable oxygen and hydrogen isotopes in plant water and organic material are of great interest in plant science, ecophysiology and climatology, since the oxygen and hydrogen isotope ratios are strongly modulated by physiological processes. Numerous studies found that δ18O is inverse proportionally related to stomatal conductance and thus indirectly climate related. In combination with the carbon isotope ratio it is possible to determine to what degree plants respond to changes in environmental conditions by changes in photosynthesis or stomatal conductance. However, for such an analysis the knowledge if the δ18O in the source water is essential, which carries a climate proxy at a span of time during the season. Lacking the isotopic information of source water leaves the physiological interpretation often with some uncertainty. Furthermore, the water vapour concentration of the ambient water vapour influences degree to which the stomata vary the plant organic δ18O. These multiple coherences will be discussed. New results show that the short term variation of δ18O in the source water was mostly significantly overestimated, which is encouraging for making use of the δ18O in retrospective analyses, i.e. tree ring studies. The further consequences of these findings will be discussed.

ABOUT LIST WATER LECTURES SEMINAR SERIES

The LIST Water Lectures series were launched in January 2017 and covers various aspects of water resources research towards a sustainable river basin management. The series aggregate a group of outstanding experts and scientists in water resources research and related fields. They are funded by the Luxembourg National Research Fund (FNR) and organised by the Luxembourg Institute of Science and Technology (LIST) in the framework of the Doctoral Training unit in hydrological sciences’ activities.