Research for climate protection: How trees can use CO2 efficiently

Research for climate protection: How trees can use CO2 efficiently

On September 25, 2025 it was announced that Prof. Dr. Jan Esper from Johannes Gutenberg University Mainz (JGU) was awarded the Reinhart Koselleck funding from the German Research Foundation (DFG) worth 1.2 million euros. His research project aims to investigate the water use efficiency of trees in relation to increasing CO2 emissions caused by the burning of fossil fuels. In this complex relationship between CO2 concentrations and the efficiency with which trees use water, scientists recognize a critical challenge for our Earth's ecosystems.

Whenever trees absorb CO2, they do so by opening their stomata, which is also associated with a loss of water. Prof. Esper believes that higher CO2 concentrations could potentially improve the water use efficiency of trees. This could have far-reaching implications for the carbon sequestration capacity of terrestrial ecosystems.

Long-term data collection and analysis

As part of his research, Esper plans to analyze wood samples from 100 locations in the Northern Hemisphere over a period of 120 years. This study is supported by a unique herbarium that provides long-term data on water use efficiency for the first time. For this purpose, drill cores from tree trunks are examined using isotope analyses. The samples are processed in Mainz and then sent to the Global Change Research Institute in Brno, Czech Republic, for analysis. This institute is capable of conducting over 100,000 isotope measurements annually, measuring stable isotopes such as carbon-13 and oxygen-18 to estimate water use efficiency.

This comprehensive methodology makes it possible to examine large-scale patterns in water use efficiency depending on different forest compositions and climate regimes. The research aims to provide empirical data on the binding capacity of atmospheric CO2, which is crucial for future climate policy.

Climate change and economic strategies

In the context of the current climate challenges, an event entitled “What Economists Really Do?” will take place on the same day. (WERD) of the Department of Economics at Oxford University in cooperation with the EBC Financial Group. This event deals with the topic of “Macroeconomics and Climate”. The aim is to research strategies on how economic systems can be designed to be ecologically sustainable and socially responsible.

The keynote speech will be given by Associate Professor Andrea Chiavari, who will address the economic costs of climate change. In a subsequent panel discussion, moderated by Associate Professor Banu Demir Pakel, Dr. Nicola Ranger from the Environmental Change Institute at Oxford University and David Barrett, CEO of EBC Financial Group, on the interplay between economic growth and climate resilience.

Dr. Chiavari highlights the need for carbon taxation to incentivize sustainable choices. At the same time, he emphasizes the social costs of CO2 as an essential factor for political measures. Dr. Ranger points to the economic opportunities that climate mitigation measures could offer, while Barrett highlights the requirements for the financial sector for an effective regulatory framework. The discussion highlights the risks associated with fragmented global action and the need for international cooperation to combat climate change.

Overall, the event not only illustrates the urgency of climate protection initiatives, but also the responsibility that both companies and private individuals have to shape a more sustainable future. Both the research of Prof. Dr. Jan Esper and the contributions of the experts at WERD show how important it is to combine knowledge and strategies in order to overcome ecological challenges.

Prof. Dr. Jan Esper is considered a leading academic in his field, while EBC Financial Group is at the forefront of responsible and sustainable innovation in the global financial landscape. The contributions of both institutions are crucial to progress towards a more sustainable future.

For further information about the research work of Prof. Dr. Jan Esper, please visit presse.uni-mainz.de. For additional details about the event at Oxford University, please visit idw-online.de, and further information on the economy and climate change can be found at globenewswire.com read up.