报告题目：Unexplored drivers of hydrogen isotope signals of leaf waxes in plants and sediments
Dr. Ansgar Kahmen is a Professor for Sustainable Land Use at University of Basel, Switzerland. His research addresses the interface between plants and their environment, with the goal to understand how plants function in the context of their environment and to reveal how plants shape the provision of ecosystem goods and services that human societies depend on. His researches have been published in PNAS, GCA, Plant, Cell & Environment and other famous journals. Among his 46 peer reviewed journal articles, four papers have been classified‘Highly Cited’ in ISI Web of Science. The h-index is 22 and the total number of citations is 1675.
Hydrogen isotope ratios (δ2H) of leaf waxes have developed into fundamentally important tools to assess and reconstruct paleohydrological changes throughout earth’s history. Originally it was assumed, that the δ2H values of leaf waxes record the δ2H values of precipitation of the area that plants live in. Progressive research has, however, revealed that additional environmental and physiological drivers can have a strong impact on what determines the δ2H values of leaf waxes. In this talk, Prof. Kahmen will present the outcome of several recent experiments from his lab where they have investigated the influences of (i) source water, (ii) leaf water, (iii) timing of leaf wax synthesis, and (iv) biogeochemical fractionation on leaf wax δ2H values. In addition, he will show recent data that highlight the contribution of atmospherically deposited leaf waxes to the sediment record in lakes.