Volker Audorff conducts research in a very interesting field for mountain bikers: sports ecology. And the effects of biking on nature are indeed one of the topics he is working on. In 2021, he demonstrated how he works in a report by Bayerischer Rundfunk.

 

What science has found out about the harmfulness, sorry, the effects of biking on nature was the subject of Ride No. 84. Volker Audorffs and other researchers have since published a scientific article that provides an even broader overview of this issue: Ecological impacts of (electrically assisted) mountain biking. The authors screened 156 studies, leaving 35 that met the criteria. Here is the answer to the question that interests many bikers - are we a problem for nature or not?

The environmental impact can be divided into three categories: Soil, vegetation and animals. Various studies have shown that mountain bikers compact the soil. This makes it more difficult for rainwater to seep away and thus contributes to erosion. In steep terrain in particular, mountain bending channels promote erosion, i.e. the removal of soil. And informal trails dig into the ground faster and lose soil than professionally built trails. E-MTBs also support soil erosion when riding steeply uphill.

It would be interesting to see how problematic this is for nature. On the one hand, how much biking contributes to overall soil erosion. And on the other hand, how much the ecological balance suffers when soil is carried away by bike tires in a few places. The research results do not provide an answer to either question.

Overall effect unexplored

The vegetation suffers most when a new path is built. This applies to both official and unofficial paths. Clearly, if a brown track runs through a meadow or green forest floor, plants have had to make way. There are differing results on the question of the extent to which the flora along the edge of the trail is affected by bikers and whether trails are becoming wider and wider due to use. In addition, tires transport seeds, which can change the plant mix where they are deposited. Shoe soles also do this, with bikes covering greater distances and therefore spreading seeds further.

The question of the overall impact on the ecosystem also remains unanswered here. The extent to which a forest or a piece of mountain landscape is affected when plants have to make way on a few paths remains unanswered. What is logical is that biking is only responsible for the loss of plants where exclusive bike trails have been built.

The picture is even more varied when it comes to the impact on wildlife. The following animal species avoid trails used by mountain bikers: chamois, bobcat, coyote, roe deer, capercaillie, bighorn sheep, red deer, mule deer and elk. No change in behavior was detected in studies of bobcat, coyote, gray fox, mountain lion, mule deer, raccoon, striped skunk, hare, tortoise, wild boar, red squirrel.

There are studies on bobcats, coyotes, moose and mule deer that show that they avoid mountain bikers at times when there are no bikers on the road. Another research study found no change in the daily routine of moose.

What will change with e-mountain bikes?There are hardly any specific studies on e-mountain bikers or comparisons between motorized and non-motorized female bikers. What is clear is that e-mountain bikers cover greater distances and, at least in theory, reach more remote (and therefore less congested) areas. This means they affect a larger area, more soil, more plants and more animals.

The 35 studies that Audorff and his colleagues have brought together say little to nothing about how biking affects the ecosystem of a region. Most studies focus on individual factors that can be observed. That alone is complicated enough. For example, when it comes to recording the behavior of wild animals and dividing them into comparable categories. The paper states: "Current debates among stakeholders are often based on individual, observable effects, while this review article has identified a lack of knowledge about how individual effects of (e-)mountain biking on soil, vegetation or wildlife can be extrapolated from the individual level to entire species, populations or ecosystems." (Translation Stefan Michel)

In other words, the impact of an individual mountain biker on soil, plants or animals can be determined. However, it is unclear what this means for the big picture, for a forest or an area. Nature reacts to us, but the extent to which it suffers from us has not been scientifically clarified. This is where the overview study calls for further research and uniform measurement rules.

In issue 84, author Stefan Michel asked researchers this question. They did not answer it conclusively either. But they came a little closer to the answer than this study.