Assessing the Environmental Effects of Mountain Biking

Mountain biking is one of the most popular recreational activities today. Sport ecologists at the University of Bayreuth have now synthesized and evaluated a wide range of previously published findings about the environmental consequences of sport. Several immediate and short-term effects on animals, plants, and soils can be demonstrated. However, estimates of long-term consequences remain difficult due to the complexity of ecosystems and their inherent dynamics. The review article has been published in the journal Global environment and conservation.

Particularly serious consequences can be seen when areas close to nature are used for mountain biking for the first time. Once areas are opened up to mountain biking by constructing new trails or mountain bikers enter intact flora and fauna on previously unexplored terrain, wild animals begin to change their behaviour. The vegetation cover is obviously affected, and the tendency to soil erosion increases. These effects are quite surprising because the areas with varied landscapes are particularly attractive and used for outdoor sports such as mountain biking.

One study evaluated showed a decrease in soil microbial biomass over a 20-m strip of terrain adjacent to trails. This impairs the supply of nutrients to plants and thus affects their growth and reproduction. The thinning of vegetation in turn increases soil erosion, which is in any case enhanced by new unpaved paths.

However, the consequences for vegetation result not only from the construction of trails, but – as other studies have shown – also from the fact that mountain bikers leave designated trails and use the adjacent terrain instead. How to assess the appropriateness of the resulting damage always depends on each individual case on their protective status and the function of the affected plants.

The destruction of vegetation in terrain used for mountain biking is particularly relevant for endangered species, but it can also have a beneficial effect on biodiversity.

Mountain biking also has a direct impact on wildlife in a number of ways, as an overview of past research shows. Wildlife often reacts to mountain biking by avoiding approaching the athletes and their trails. It is not uncommon for cyclists to shorten their rest periods and interfere with their feeding at their usual times of the day.

Therefore, some species change both their habitats and their circadian rhythms. The effects of mountain biking have been studied most frequently in mammals and birds. However, potential changes in behavior do not necessarily have negative effects on the numbers of the species involved.

In their review, the Bayreuth mathematical ecologists clearly point out gaps in knowledge. Many aspects of the interactions between mountain biking and flora and fauna have not been adequately studied and are likely to vary greatly between individual species. Also, not much is known yet about the consequences of the rapid spread of electric-powered mountain bikes.

“There is already a lot of evidence that the environmental effects identified in previous studies are enhanced by e-mountain biking. However, a great deal of research is still needed before valid data can be released in general. Not least, it will have to These also investigate changes in sporting behavior associated with switching to electric-powered mountain bikes,” said Veronica Mitrowollner, author of the review article and doctoral student in the Sport Ecology Research Group at the University of Bayreuth.

The authors of the new publication stress that the knowledge available thus far regarding the direct environmental impacts of mountain biking is rarely sufficient to enable conclusions to be drawn regarding long-term consequences for ecosystems. In many cases, much more data may need to be collected than is available today to draw reasonable conclusions about the nature and extent of potential long-term effects.

“In principle, the effects of mountain biking can be expected to vary greatly between species and depend on the context. Targeted investigation of rare species or species worthy of protection has so far often been insufficient, and the significance of short-term disturbances thus remains open,” Mitrowollner said.

Bayreuth sports ecologists also point out that outdoor sports such as mountain biking can contribute in the long term to making people aware of the aesthetic and ecological value of landscapes. In this case, these sports will have the potential to strengthen an environmentally conscious approach to nature.