Matthias Wantzen is a Researcher Dedicated to Water

“The French Revolution started because of hunger. The coming revolutions will probably begin because of thirst. We need a fast and efficient change in the direction of sustainable and fair water management. Time is already running out, and the longer we wait, the more extensive the measures will be for the population, which could threaten our democracy,” says Professor Matthias Wantzen, who has devoted his life’s work to the research of bodies of water.

Wantzen’s academic career began in Germany in 1992, when he was researching the distribution patterns of invertebrates in the Rhine riverbed: “When the chemical accident occurred at the Sandoz company in Basel, the pesticides that flowed into the river killed a large percentage of the fish and invertebrates. While researching 700 kilometres of the Rhine, for which dredgers and diving bells were used, I was able to demonstrate that animals could be found at a depth of up to one meter in the sediment, from where they were later able to repopulate the Rhine.”

Eight years in Brazil

In 1993, the scientist left Germany for Brazil, where he wrote his PhD thesis about the effects of agriculture on biodiversity in headwater regions. This was followed by a postdoc study on food chains in the Pantanal wetlands in Brazil. He stayed in Brazil altogether eight years, serving as the coordinator of a scientific cooperation project and helping to found a master’s degree course and a research institute.

After Brazil, he did research in Switzerland before he completed a postdoctoral thesis to qualify as a professor (habilitation) at the University of Konstanz. While there, he founded a working group that addressed the functional ecology of the flood zones of rivers and lakes. His primary objective with this group was to understand how the physical conditions and the chemical composition of the water and the life of the organisms mutually influence each other.

Wantzen’s next focus of research was Lake Constance, which is where the Alpine Rhine meets the High Rhine. “Since the Rhine became connected with the Danube through the Rhine-Main-Danube Canal, invasive species from the Black Sea have come all the way to Lake Constance,” he says. In 2010, he then accepted the offer of a professorship at the University of Tours. “Since I was little, I have always felt a deep connection to France,” admits the multi-lingual researcher. After moving to France, he began to research the Loire River.

Saving the last giant freshwater pearl mussels

The year 2014 was a turning point for Wantzen. He was able to acquire funding from the EU’s LIFE programme to save the last Margaritifera auricularia, a species of freshwater pearl mussels also known as giant freshwater pearl mussels. “This species of mussels also used to exist in the Rhine but it died out there 150 years ago. It can still be found in certain rivers today, however. With the help of artificial reproduction, this species can be saved from extinction,” he says.

In the same year, he was appointed to the UNESCO Chair of Rivers and Heritage at the University of Tours. There, he applied his experience from the Global South to the development of an international master’s degree course that focuses on land-use planning and sustainability. In this programme, he had European and international students work together in small teams. “It is one of my responsibilities to overcome cultural barriers,” the scientist explains, emphasising how important it is for students to learn how to think critically and be open for the ideas of others.

At the University of Tours, he also began to put together an interdisciplinary book with the title River Culture: Life as a Dance to the Rhythm of the Waters. More than 120 authors from 25 countries were involved in this work in which he demonstrates that the diversity of human cultures in flood zones follows the same principles as biological diversity and is also vulnerable to the same threats. As the species of freshwater animals decrease (according to a report by the WWF by more than 84% since 1970), cultural forms like artisanal fishing are also disappearing. Hardly any professional fishermen are left on the Rhine today, for example, and local residents have increasingly fewer cultural connections to the river.

In favour of new water policies that take the protection of non-human life forms into account

Wantzen became the holder of the cross-border Eucor chair in Sustainable Water Management on 1 September 2023. The chair was established by the University of Strasbourg in collaboration with the Karlsruhe Institute of Technology (KIT) and is supported by the National School for Water and Environmental Engineering of Strasbourg (ENGEES). “I usually worked alone on my areas of research in Tours, but here several teams work together, especially the Institut Terre et Environnement de Strasbourg (ITES - CNRS/Unistra/Engees) and the Laboratoire image, ville, environnement (Live, Unistra/Engees/CNRS),” says the scientist happily, while also emphasising the advantages of the Eucor network and the close collaboration with KIT.

Wantzen is an active researcher in the OneWater project of the French excellence initiative PEPR, which he says “is about interdisciplinary models for better water policies that also take the protection of non-human life forms into account.” He is also still committed to water research in Brazil. He adds, “We must restore the functionality of river basins. Catchments must become the measure for all decisions concerning water policies. Culture and biological strategies could be the key to mastering future crises.”

Marion Riegert