Natural Resource Impacts of Mountain Biking

Mountain Biking is still a new sport. It's about 30 years old. The General public doesn't really know what Mountain Biking is and how it affects the property that Mountain Bike trails are on. Here is some info. Please pass it along.

  recent years, hiking and environmental groups have lobbied to ban mountain bikers from trails on the grounds that mountain bikes damage the environment. Some land managers have closed trails to bicycling because of alleged, excessive resource damage.


Do mountain bikers truly cause more impact on natural resources than other trail users?


Very little research has been in done in an attempt to answer this question, but the empirical studies that have been conducted do not support the notion that bikes cause more natural-resource impact. What studies do demonstrate is that all forms of outdoor recreation - including bicycling, hiking, running, horseback riding, fishing, hunting, bird watching, and off-highway-vehicle travel - cause impacts to the environment. 1


Social scientists have conducted surveys to study the feelings, perceptions, and attitudes of cyclists, hikers, equestrians and motorized trail users toward one another. This information, along with anecdotal evidence and media reports, shows that trail users don't always get along. User conflict, as a concept, is fairly well understood and demonstrably real.


In a democracy, the allocation of trails based on users' differing interests is a normal, appropriate course of action. Land managers must consider the opinions and concerns of the people who use their trails. But when individuals make unsubstantiated allegations regarding natural resource damage to justify the prioritization of their type of trail use, land managers should be wary.


Objective information, independent of conflicting human desires, must be the basis for sound policy decisions. The results of scientific studies can provide land managers and recreationists with a better understanding of user impacts, and should guide political debate and public policy.


This document examines three main categories: physical impacts to trails or facilities, vegetation damage, and effects on wildlife.


In each case, several studies have examined the topic, but only a handful have compared the effects of bicyclists with other trail users.


No scientific studies show that mountain bikers cause more wear to trails than other users.


Trails deteriorate over time. To what extent do bicyclists cause this deterioration, and how does the impact of bicyclists compare with that of other trail users? Many people have hypothesized about impact, basing their theories on ideas involving the characteristics of tires versus shoes, skidding, area and pressure of impact, and other factors. But as of 2003, only two empirical studies have scientifically compared the erosion impacts of bicycling with other forms of trail travel. (editor: For a more recent and complete review of scientific studies, see Environmental Impacts of Mountain Biking: Science Review and Best Practices by Jeff Marion and Jeremy Wimpey published in Managing Mountain Biking: IMBA's Guide to Providing Great Riding (2007).


Wilson and Seney: Hooves and feet erode more than wheels
In 1994, John Wilson and Joseph Seney of Montana State University published "Erosional Impacts of Hikers, Horses, Motorcycles and Off-Road Bicycles on Mountain Trails in Montana" (12). The study tracked 100 passages by each of the four groups over control plots on two trails in national forests. For some of the passages, the researchers prewet the trail with a fixed quantity of water using a rainfall simulator. The researchers measured sediment runoff, which correlates with erosion.


Wilson and Seney found no statistically significant difference between measured bicycling and hiking effects. They did find that horses caused the most erosion of the trails, and that motorcycles traveling up wetted trails caused significant impact. They also concluded, "Horses and hikers (hooves and feet) make more sediment available than wheels (motorcycles and off-road bicycles) on prewet trails, and that horses make more sediment available on dry plots as well" (p.74). Wilson and Seney suggested that precipitation will cause erosion even without human travel, and this factor may significantly outweigh the effects of travel. Trail design, construction, and maintenance may be much more important factors in controlling erosion than excluding specific user groups.


Conclusion


Mountain biking, like other recreation activities, does impact the environment. On this point, there is little argument. But people often debate whether or not mountain bikes cause more damage to trails, vegetation, and wildlife than other forms of recreation such as hiking and horseback riding.


A body of empirical, scientific evidence now indicates that mountain biking is no more damaging than other forms of recreation, including hiking. Thus, managers who prohibit bicycle use (while allowing hiking or equestrian use) based on impacts to trails, soils, wildlife, or vegetation are acting without sound, scientific backing.


A land manager's decision to prohibit one user group on the basis of providing a particular type of experience for another group may or may not be justified by evidence provided by social studies, as the wisdom of prohibiting a particular user group in order to satisfy the desires of another is a matter for politics rather than science.