Many surface waters in Lower Saxony are heavily polluted with nitrate. Members of the public can now determine the levels themselves, either by wading knee-deep into their nearest stream or from home using the ‘nitrogen box’,in collaboration with researchers from the Universities of Oldenburg and Osnabrück .
It can be found in salami and even in a lettuce leaf: nitrate is a vital nitrogen compound which, in the right dose, helps nature along. However, in excessive amounts, nitrate can be harmful to both people and the environment. For example, too much nitrate in the natural environment not only causes eutrophication of water bodies and soil but also harms biodiversity. But why does nitrate act as a fertiliser? How does this nutrient end up in the groundwater? And just how polluted are our water bodies?
A project run by the Universities of Oldenburg and Osnabrück is addressing these questions. What makes this project special is that members of the public are becoming nitrate researchers themselves. Using simple methods, they measure nitrate levels in surface waters such as streams or wells. The researchers in Oldenburg are also providing some participants with an experiment kit so that they can explore the topic in even greater depth.
However, the project does not just bring scientists and members of the public together: schools from the north-west are also involved in the initiative. In seminar modules, sixth-form students spend two years studying the nitrogen issue and related research projects in depth. Acting as ‘mentors’, they supervise small groups of interested pupils during the nitrate measurements and explain the testing method to them.
Both sides benefit
“The issue of nitrate affects everyone in our region,” says Prof. Dr Verena Pietzner, a chemistry education specialist from Oldenburg, who leads the project together with Prof. Dr Marco Beeken from the University of Osnabrück. In many parts of northern Germany, surface water is contaminated with nitrate, which can have an impact on groundwater. And a so-called citizen science project on nitrate is a good opportunity to raise awareness of the issue amongst households. Ultimately, both sides benefit: participants provide additional data for research and, alongside learning scientific working methods, also discover what is happening in the environment on their doorstep.
The approach of bringing non-scientists together with researchers is not yet very widespread in chemistry. But Pietzner is keen to see it happen: “In the 19th century, people attended evening events on the natural sciences just as they go to the theatre today. It would be lovely to revive this curiosity about science.”
Soil in a returnable bottle
The curiosity of the more than 600 amateur scientists who have already registered with the project partners in Osnabrück gives cause for optimism. The researchers in Osnabrück are responsible for the first phase of the project, which is receiving technical and financial support from the German Federal Environmental Foundation until March 2020. They are providing members of the public with small test strips that indicate the nitrate content in the respective surface waters. The amateur scientists upload the data they collect online.
In Oldenburg, Pietzner, together with her doctoral candidate Mientje Lüsse, has developed an experiment kit for the second part of the project. Fifteen different experiments for young and old alike encourage tinkering and experimentation. A leaflet contains instructions and background information. The materials required for the experiments are either included in the experiment kit or can be found in any household. For example, a simplified model of the soil can be recreated using just a PET bottle, some sand, gravel and a coffee filter. If a nitrate or ammonium solution is then added, it becomes clear how soil without plants filters out the ammonium but not the nitrate. In this way, in reality, it can seep into our groundwater. Plants, on the other hand, are able to absorb nitrate from the soil; for this reason, it is important to ensure that soil is covered with vegetation wherever possible.
Experimenting as food for thought
The accompanying booklet also contains tips on how any individual can reduce their personal nitrate emissions. “Small things already make a big difference: for example, only buying as much as you use, or eating less meat,” explains Lüsse. Like her colleagues in Osnabrück, the doctoral candidate is also in close contact with the participating schools. The sixth-form students are putting the experiment kits through their paces. Among other things, they are assessing how clear the information is and how easy the experiments are to carry out. The researchers are incorporating the pupils’ feedback before releasing the experiment kit to the public. Around 100 amateur scientists will then receive the kit early this year.
In late summer and autumn, Pietzner and Lüsse will finally interview the participants about their experiences with the experiment kit. “We hope that both members of the public and school pupils will be inspired to reflect on these issues through experimentation. And we’d like to find out whether this leads to a change in attitudes towards environmental issues,” says Lüsse. Organised by the pupils, the project will conclude with several exhibitions. Scientists from Osnabrück and Oldenburg will both present their findings there. Until then, a number of amateur scientists will continue to wade through streams and use returnable bottles for their experiments.
