A laboratory in nature
Anyone going for a walk in the ‘Amtsvenn-Hündfelder Moor’ on the German-Dutch border can discover a technical infrastructure in the middle of the European nature reserve. What is it all about? “The best way to describe it is as a laboratory in nature,” says Prof Dr Mana Gharun from the Institute of Landscape Ecology. The Associate Professor of Biosphere-Atmosphere Interaction is using a so-called long-term eddy covariance measurement system to investigate the exchange of greenhouse gases between the peatland and the atmosphere. “We know that peatlands have an important function as carbon storage for climate protection. However, there are hardly any intact peatlands left in Germany. Although there are numerous projects to restore these ecosystems - i.e., to rewet them - there is very little long-term data available on how the entire process of rewetting peatlands affects the climate,” explains Mana Gharun. The scientist now aims to improve this.
For decades, peatlands have been drained, for example for agriculture or forestry. According to the Federal Environment Agency (Umweltbundesamt), drained peatlands in Germany emit around 53 million tonnes of carbon dioxide equivalents every year, which corresponds to around 7.5 percent of national greenhouse gas emissions. Today, more than 95 per cent of national peatlands are no longer in a natural state, but have been heavily modified. Mana Gharun´s team has been investigating the feedback from the Amtsvenn-Hündfelder Moor to the climate since 2022. As part of Nicolas Behrens' PhD thesis project, who is managing the station a fully automated measuring system was installed in September 2022. The infrastructure allows the research team to monitor greenhouse gas emissions before, during and after rewetting– 24/7, under natural conditions, for the first time. This way the researchers can make quantified statements about the interplay between peatland restoration and the effects on the climate.
The data is collected continuously with a high frequency - ten times per second to be precise. The measuring system recently achieved the status of a certified station of the ‘Integrated Carbon Observation System’ (ICOS). This is a European research infrastructure for the long-term, precise and internationally comparable measurement of greenhouse gases. “We can check and process everything conveniently in the office. The data arrive directly on our servers,” says the climate expert. The researchers carry out the analyses with the help of artificial intelligence. So far, they have been able to determine that the peatland acts as a carbon sink or source depending on the year and that these states depend on various variables such as temperature and precipitation.
The team not only measures carbon dioxide as an important greenhouse gas, but also takes a comprehensive approach: in addition to nitrous oxide and methane, over 60 other variables such as soil and air temperature, wind speed and radiation are included in the monitoring. “This is comparable to an illness where physicians look for both the cause and a treatment. To do this, they collect various values such as blood pressure, weight and nutrient levels. It is similar with the peatland: we want to find out what drives the gas fluxes and emissions of the ecosystem. Each measurement provides a piece of the puzzle, and together they form the foundation for decisions on the management of the peatland,” explains Mana Gharun.
Her working group is tackling this complex task in cooperation with many experts. At the Institute of Landscape Ecology, she works closely with peatland expert Prof Dr Holger Knorr and remote sensing expert Prof Dr Hanna Meyer. The Zwillbrock Biological Station, which is responsible for rewetting, also contributes its expertise.
Mana Gharun is keen to integrate the research into her teaching. In particular, she wants to encourage female students to familiarise themselves with the technical details. “Many women are still reluctant when it comes to setting up a technical infrastructure. I encourage them to participate and explore this area,” she says. “Many students end up discovering a new passion and enthusiasm during their time at the university.”
The research team hopes to use the long-term data to contribute to concrete peatland protection. In addition, the new findings are to be incorporated into climate policy measures to reduce greenhouse gas emissions and thus mitigate the effects of climate change.
Author: Kathrin Kottke
This article is taken from the university newspaper wissen|leben No.8, 11. December 2024.