Research Interests

• Phylogeny and phenotypic adjustment
• Functional traits
• Ecological evolutionary adaptation
• Nitrogen Isotope

Project
Human activities have dramatically influenced the global environment with potentially severe impacts on terrestrial ecosystems and the services they provide to society. In particular, the anthropogenic emissions of reactive nitrogen that is deposited in terrestrial ecosystems is an environmental problem that is often overlooked by the public. Being able to characterize the eutrophication of terrestrial ecosystems as a consequence of reactive nitrogen deposition is an essential task to understand and potentially mitigate the impacts of reactive nitrogen deposition on ecosystem goods and services. The stable nitrogen isotope composition of plant leaves (δ¹⁵N values), which has been suggested to reflect nitrogen cycling in the soil. All of these studies have shown that foliar δ¹⁵N values have declined in the last century. Importantly, this interpretation of declining foliar δ¹⁵N values indicating a progressive nitrogen limitation of terrestrial ecosystems is in sharp contrast to widespread deposition of reactive nitrogen at very high rates in the ample reports of an eutrophication of terrestrial ecosystems. We hypothesize the cause of this paradox is that current interpretations of foliar δ¹⁵N time series ignore the fact that plants adjust their photosynthetic machinery as a function of CO₂ supply, where photosynthetic capacity is typically downregulated with increasing CO₂ by reducing the nitrogen investment in foliar tissue. At present, it’s difficult to separate the effects of the δ¹⁵N values of the plant's
nitrogen source in the soil from plant internal effects as the drivers of foliar δ¹⁵N values. In this study, we will use some new technical methods to separate the effects of soil nitrogen cycling from the effects of plant internal effects (nitrogen allocation and assimilation in response to carbon dioxide) on leaf δ¹⁵N to resolve the paradox between the decline of δ¹⁵N in plants and eutrophication in terrestrial ecosystems.

Education
2024-ongoing PhD student in the Physiological Plant Ecology group, University of Basel, Switzerland
2019-2023 M. Sc. in Botany, University of Chinese Academy of Sciences, China
2015-2019 B. Sc. in Agriculture Science, Yunnan Agricultural University, China

Publication
Liu JM, de Vos JM, Körner C, Yang Y (2023) Phylogeny and phenotypic adjustments
drive functional traits in Rhododendron across elevations in its diversity hot-spot in W-China. Alpine Botany. https://doi.org/10.1007/s00035-023-00294-5