STAznanost

Ljubljana bike routes studied for their impact on people

Ljubljana, 7 August - In a time of a climate crisis and heavy traffic in city centres, more and more people take to cycling. Researchers at the Ljubljana Jožef Stefan Institute are taking a look at how polluted air, noise and high temperatures of the urban environment affect Ljubljana's cyclists.

Cycling is not only a popular hobby but also an environmentally-friendly alternative to cars, which in Slovenia are still used for more than half of the journeys shorter than five kilometres. Cycling normally helps improve physical and mental health but cyclists in cities are more exposed to urban environmental stressors, such as polluted air, noise and high temperatures, than individuals driving in cars.

In the last decade many clinical studies have pointed to a link between the exposure to urban environmental stressors and negative impacts on health. One of the more obvious connections is the effect of long-term exposure to polluted air which can lead to different respiratory diseases, researcher Rok Novak told the STA.

High temperatures are becoming a more common stressor and have a larger effect on people in cities where they feel the heat more because of the built-up environment.

Noise too can negatively affect physical and mental health. "The special thing about noise is that we are often not even aware of it and we subconsciously dismiss it, even though it is as harmful as the other stressors," said Novak.

The institute has set up an urban cycling lab as part of the four-year URBANOME project to study the extent to which cyclists in Ljubljana are exposed to the urban environmental stressors on different routes.

Popularity of cycling in Ljubljana

Slovenians completed 1.5% of their daily journeys on bicycles in 2017 and 2.2% in 2022, shows data by the Statistics Office. "The increasing popularity of cycling on short distances could be attributed to increased environmental awareness and a desire for a healthier lifestyle," said Maria Alejandra Rubio, a doctoral student from Columbia who is working on the project.

Researchers working on the project are mostly interested in how the environment affects the decision-making of cyclists. They will compare cycling on the less adapted urban routes and cycling on the "green cycling corridors", which are slow zones with clearly marked and safe cycling lanes.

Volunteers at the heart of the research

The project relies on volunteer cyclists to collect the data. Researchers equip every volunteer with three devices to measure air quality, temperature, noise and pulse and track them while cycling for 14 days.

The devices are on the more affordable side, which is why the measurements are less reliable and less precise. They have to be calibrated often and the measurements compared with those of better devices. "Bear in mind that these devices are not used to draw scientific conclusions, we use them to detect patterns and trends," said Novak.

Volunteers are involved with the project from start to finish, not just in the data-collection stage. "Because of this approach they feel a sense of belonging and claim the results as their own. They can understand the results better and can change their habits better than if they just read some recommendations," said Novak.

Dol pri Ljubljani
Devices measuring urban stressors at the Jožef Stefan Institute's Department of Environmental Sciences.
Photo: Bor Slana/STA

Social sciences at work

The researchers look for connections and patterns in the data using computer models. To make it easier to interpret and contextualise the findings, they also used some research elements typical for social sciences, said Novak.

According to Rubio, they are introducing a concept of ride-along interview, where volunteers are asked about their mood, impressions and reasons for their decisions during the ride. "We mostly want to better understand the thought process of cyclists when choosing their routes. We also rate to what extent they are aware of the environmental stressors and how that affects their decisions," she said.

These findings are then combined with the measurements into agent computer models, which can give more meaning to raw data. "We can effectively simulate people's behaviour and detect patterns that we otherwise couldn't," said Novak.

Dol pri Ljubljani
Rok Novak, a researcher at the Jožef Stefan Institute's Department of Environmental Sciences.
Photo: Bor Slana/STA

Improving the environment

Understanding the social patterns is crucial both for individuals and for decision-makers designing environmental and spatial policy. The findings of the project will allow individuals to better understand their environment and allow them to adjust their activities to lessen the exposure to pollution.

"Individuals equipped with the data can make more clear demands for decision-makers and can reach shifts in spatial planning policy faster," said Novak.

Cycling is currently one of the best solutions for environmental and mobility challenges of the urban areas, said Rubio, adding that "if we want people to sit on a bicycle instead of in a car, we have to ensure well-being, health, safety and comfort on cycling routes". "In the future cycling will be key in creating resilient, lively and sustainable urban environments around the world," she said.

Dol pri Ljubljani
Maria Alejandra Rubio, a researcher at the Jožef Stefan Institute's Department of Environmental Sciences.
Photo: Bor Slana/STA