When citizens contribute to science

The boardwalk stretches across the wetland like a narrow ribbon through the landscape. Around it, water glimmers between mosses and grasses. A visitor pauses, notices a sign, and takes out their phone. A quick scan of a QR code reveals a simple task: measure the water level, take a photo of the vegetation, perhaps record the temperature of the soil. It takes only a few minutes. Yet the observation may become part of a much larger story on how Europe restores some of its most valuable ecosystems.

This is citizen science in action.

According to researchers working on two major European projects, WET HORIZONS and NBS4Drought, it may help solve one of the biggest challenges facing environmental science today: how to monitor nature over the long term.

Beyond the scientists

“Citizen science is about citizens in science,” says Lorenzo Pugliese, special consultant at the Department of Agroecology, Aarhus University.

But the concept goes far beyond asking volunteers to collect data.

“It is not a one-way relationship,” he explains. “Citizens contribute to science, but science also gives something back: knowledge, engagement, and a stronger sense of belonging to a place.”

That exchange is becoming increasingly important as researchers try to understand how ecosystems respond to restoration efforts. Wetlands, peatlands and other nature-based solutions evolve slowly. Their recovery may take decades, while most research projects last only a few years. Researchers can monitor a site during the lifetime of a project. Afterwards, funding often ends and systematic monitoring becomes difficult.

“We restore a site, maybe monitor it for four years, and then we don’t know exactly what happens afterwards,” says Lorenzo Pugliese. “At the same time, it is physically impossible for researchers alone to monitor hundreds of sites over long periods. Citizen science can help fill that gap.”

The challenge is particularly relevant for peatlands. They cover only around three percent of the Earth’s surface, yet they store twice as much carbon as all the world’s forests combined. They support rare biodiversity and help regulate water, reducing both drought and flooding risks. Monitoring whether restoration projects work is therefore crucial.

A living lab in Lille Vildmose

For WET HORIZONS, Lille Vildmose in northern Denmark offers an ideal testing ground. The area is one of Northern Europe’s largest raised bogs and attracts thousands of visitors every year. Many of whom already have an interest in nature and conservation.

“We knew that people visiting Lille Vildmose often know quite a lot about wetlands, plants and wildlife,” says Lorenzo Pugliese. “So, we thought it would be a good place to test citizen science activities.”

Researchers established monitoring stations both inside the visitor centre and out in the landscape. Visitors can measure groundwater levels using specially designed floating rulers, record soil temperatures with simple thermometers and upload photographs of plants, animals and the surrounding landscape. The tools are intentionally simple.

“We tried to create something very handy and user-friendly,” he says. “People receive instructions through QR codes, take the measurements and report them online.”

To the researchers’ surprise, the outdoor monitoring station proved more popular than the one inside the visitor center. People seemed eager to participate when they encountered the activities directly in the landscape.

Can the data be trusted?

The promise of citizen science is obvious. Thousands of visitors can potentially collect observations that no research team could afford to gather on its own. But a fundamental question remains: can the data be trusted? That question became a central part of the WET HORIZONS experiment. 

Rather than immediately using citizen-generated data for scientific conclusions, the researchers first focused on validating the approach. They installed automated sensors that continuously measured water levels and soil temperature. These professional measurements could then be compared with observations submitted by visitors.

“We wanted to test the activities, but we also wanted to validate the data,” says Lorenzo Pugliese. “If we can prove that the approach works, then we can use it and scale it up elsewhere.”

The need for validation reflects a broader challenge within citizen science. While volunteer observations have enormous potential, environmental researchers still lack robust frameworks for integrating such data into scientific monitoring programmes. According to Lorenzo Pugliese, this is one reason why citizen science remains underestimated despite its growing popularity.

“I think it has the power to influence policy,” he says. “But we need more structured approaches and stronger frameworks to demonstrate that the data can be used reliably.”

More than data collection

Yet citizen science is about more than numbers. As researchers have discovered, the success of a project often depends as much on communication as on methodology. One experience particularly stayed with Lorenzo Pugliese. During the 20th anniversary celebration of Lille Vildmose, he met a Danish high-school teacher who stopped by the WET HORIZONS stand. She read the project’s educational material and explored the monitoring activities. The reaction surprised him.

“She was extremely happy about the way we were telling the story”, he recalls. “She thought it would be very engaging for her students.”

For Lorenzo Pugliese, the encounter revealed something important.

“The power of communicating an idea is the first step. If you miss that step, you lose the opportunity. You lose a citizen, and then you lose a measurement.”

That insight echoes findings from recent research on citizen science. While apps, smartphones and QR codes make participation easier, people’s motivation often comes from something deeper: a connection to a landscape, a desire to protect nature, and a wish to contribute to science and society.

The future of restoration

Citizen science is already becoming a familiar component of European environmental projects. In NBS4Drought, which investigates how wetlands can function as nature-based solutions to increasing drought risks, citizen engagement is again part of the picture. This is a new and effective way to achieve impact – both within the natural and the human environments.

According to Lorenzo Pugliese, future restoration efforts will likely depend on closer collaboration between researchers and citizens. Not because volunteers can replace scientists. But because the environmental challenges facing Europe have become too large for science to tackle alone.

As the European Union pushes forward with ambitious restoration targets, researchers need better ways to understand how ecosystems change over years and decades. That knowledge may come partly from satellites, sensors and scientific field campaigns. But it may also come from ordinary people walking through a wetland, stopping at a QR code, and deciding to spend a few minutes helping science.

More information
Read more about the projects here: Wet Horizons and NBS4Drought

Contact:
Special Consultant Lorenzo Pugliese, Department of Agroecology, Aarhus University. Tel.: +45 93521064 or mail: lorenzo.pugliese@agro.au.dk 

Communications Advisor Camilla Brodam Galacho, Department of Agroecology, Aarhus University. Tel.:+45 93522136 or mail: brodam@agro.au.dk