Assessing and Understanding Environmental Impacts of Mountain Bike Technical Trail Features Christopher Kollar*, Yu-Fai LeungNorth Carolina State University

Department of Parks, Recreation and Tourism ManagementIntroductionResearch Purpose

A considerable amount of issues relating to mountain bike use impacts has surfaced in the last two decades. Social and environmental impacts of the estimated 50 million mountain bike users in the United States as of 2008, has elicited concern from resource managers and outdoor recreation resource researchers (Outdoor Foundation, 2009: Shimano & International Mountain Biking Association, 2008). In response, mountain bikers have united together in large associations such as the International Mountain Biking Association (IMBA), and Triangle Off-Road Cyclists (TORC). Mountain bike associations are advocating and funding mountain bike trail construction projects all over the world, based on research showing mountain bike impacts to be similar or less than traditional trail activities (Webber, 2007). Although literature confirms similar environmental impact levels associated with mountain biking, hiking and horseback riding, it also references the fact there are no assessment tools to measure mountain bike specific impacts. The purpose of this study was to develop a mountain bike specific, impact assessment tool (Cessford, 1995; Pickering, Newsome, Hill, & Leung, 2010). In order to understand specific mountain bike use impacts we developed an assessment tool that measures environmental impacts related to technical trail features that exist primarily for mountain bike use.

Specific Mountain Bike Impacts Difficulties understanding mountain bike related impacts stem from the variety of rider types within mountain biking itself. The International Mountain Biking Association (2006) references six different rider types: all-mountain, cross country, downhill, free ride, racing and urban, each having different preferences, motivations, attitudes and skills. With such a diverse user group the demand on resources and management have led to access and environmental impact issues. One specific rider type called free riding, a combination of all other rider types, has been associated with high levels of environmental impact and the use of technical trail features (TTFs). In this study we have defined TTFs as armoured, natural features or built structures that enhance mountain bike riding experiences through physical and mental challenges. These features are found predominately in areas where natural terrain does not provide the physical and mental challenges riders desire. TTFs have presented resource managers another challenge for protecting resources while providing desired outdoor recreation experiences.

Current State of Literature Previous studies have assessed mountain bike impacts through tools created for environmental assessment of traditional trail recreation activities. This limited approach has found significant mountain biking impacts associated trail design, user behavior and trail conditions but does not incorporate specific mountain bike elements. These studies have found high levels of environmental impact associated with steep slopes, curves, wet conditions, skidding and braking (Symmonds, Hammit, & Quisenberry, 2000; Marion & Wimpey 2007; Thurston & Reader, 2001). The consensus is that mountain bike impacts are similar or less than other permitted trail uses. However, only two studies (Newsome & Davies, 2009 and Pickering, In Press) have incorporated technical trail features in their assessments. In essence this study provides two purposes; one to continue the development of an assessment tool that measures mountain bike specific impacts and the attain a larger breadth of knowledge about mountain bike impactsMethods

Study Site Mountain biking in its short history has already become specialized and has its own terms that riders have constructed to describe their experiences and features. To properly assess the features and ensure accuracy we constructed a feature identification guide that had pictures and technical terms for all known mountain bike features. The field identification guide was used to survey several mountain biking sites within the Research Triangle Area of North Carolina to see what features were present here and to find an adequate research site. Potential study sites were found through a popular mountain biking website (www.trianglemtb.com) and talking to local mountain bike users. Legend park, a 24 acre heavy vegetated Urban park located in Clayton, North Carolina was selected as the study site for it's variety and total number of technical trail features (n=86). This site was also chosen for it's high visitation rate among Research Triangle Area mountain bike riders. Legend park was constructed by the Town of Clayton and local mountain biking advocates and is managed by the Town of Clayton. Legend park has nine different trails that combine to form over eight miles of trail with varying skill ratings. This site is known amongst Triangle Area riders for its' large hucks which are steep drop offs and technical built structures.

Instrument The instrument chosen for this study was adapted from two Australian studies, Pickering (In Press) and Newsome (2009), to assess technical trail features found in the United States. A field test of Pickering (2010) and Newsome (2009) found the presence or absence of certain feature, safety and managerial components. The final instrument (Table 1) used examined technical trail features and its proximate areas for environmental, safety, social and managerial issues. In total there were 28 different elements that were used to assess the technical trail features. Comprehensive field procedure and data forms were field tested and finalized to ensure accuracy amongst the researchers. During the field tests it became apparent that a circular observation zone (COZ) would be the most efficient, systematic way to assess the features and their respective impact. The COZ consisted of a flagged circle around the feature that had a radius half the size of the technical trial feature. This observation method allowed for a more complete assessment that included all trail features and their proximate areas. Standard trial measurement tools were used for the assessment procedure including a metric wheel, metric rulers, a SUUNTO Tandem clinometer/compass combo, and a Garmin GPS Unit (Oregon 550 with digital camera). Research teams were organized into two teams of two where one member took measurements while the other entered data onto the field data form. The observation period lasted one month during the fall season of 2009.

Results A total of 86 technical trail features we identified and assessed at Legend Park. Of the 86 TTF's forty-two features were built technical features, 23 were natural trail features and 21 were built enhanced features. The experience grouping had 39 traverse features, 32 aerial features and 15 ground features. The frequency of features (feature per unit area) was one for every 149 meters. There were no significant differences for environmental, safety, social and managerial components found between the composition (BTF, BE, NTF) groups. However, there were significant differences found between the experience (aerial, ground, traverse) groupings and amongst the technical trail features within the experience groups. Results from the one-way ANOVA, shown in Table 2, found significant differences at the 0.05 level among the experience groups for the following variables: TTF length, TTF maximum height, trail incision, trail slope and landscape slope. Aerial groups (Figure 3) were associated with higher maximum height, trail incision and larger trail slope. Ground features ( Figure 2) were associated with longer feature length and larger landscape slope. Traverse features (Figures 1 & 4) had the smallest mean feature length, maximum height, trail incision, trail slope and landscape slope.

Group differences using the chi-square analysis found several trends in the data. Aerial features were more likely to be in cleared areas than traverse or ground features that were predominately on trail. Ground features were almost always found by heavy vegetation and a closed canopy while traverse and aerial groups were found near light vegetation and moderate canopy openness. The traverse groups had much less root exposure around features than either aerial or groups group features which were heavily associated with root exposure. The Chi-square analysis within experience groups found significant differences at the 0.05 level amongst the features within each group. The traverse group had the most variance among features with four significantly different variables while the ground group had the least variance with only one significantly different variable. Two variables, root exposure and canopy openness, were found to be significantly different amongst the aerial group. Drop-off features had one hundred percent of features showing root exposure while the other features had a mixture of presence and absence of root exposure. The drop-off features were also associated with open canopy more than the other features. The ground group had only one variable, native vegetation removed to construct feature, showing significant difference among its' features. Berms were heavily associated with the presence of removed native vegetation while rock gardens and whoop-de-doos were more naturally existing. The final group, traverse, had the most variance amongst the highest total number of features in any group. Trail feature condition, native vegetation removed to construct feature, trail type and root exposure differences were all significant at the 0.05 level. Bridge, boardwalk and skinny features had higher condition scores and were not associated with removal of native vegetation. Log ride and boardwalk features were associated with less root exposure than the other technical trail features within the traverse group.

Discussion The adapted framework based on experience categorization proved to be an efficient way to assess and understand technical trail features found on mountain bike sites. This conceptual model allows for the assessment of mountain bike specific impacts that can be added to the traditional trail assessments to gain an overall understanding of mountain bike impacts. The composition categorization does provide information about how features are built but it does not provide a clear image for the assessment of environmental, social and managerial elements. However, the categorization based on experience does provide useful insight on the environmental, social and managerial issues that are debated today. Using the experience group categorizations can provide specific mountain bike assessments, specific feature assessment and comparison, areas where certain features may not be suitable, and possible substitution of features. It is plausible that groups have differences among them since they have been constructed to provide different experiences. Previous research has shown that riders prefer variability among trails and experiences. That has been one of the major issues for managers as they struggle to provide all the experiences that several rider types prefer. This adapted model shows the f variability amongst features and groups and incorporates that into the assessment tool. The length and height of features vary between groups as does trail and landscape slopes. These variables have been heavily studied components of trail elements that are found on mountain bike sites but have not been examined in the form of technical trail features. Within the groups there is also variability amongst the features that provide similar experiences. The differences here are due to composition differences between features. More variability was found within the traverse group because it had the most features providing the same experience. These features are providing the same function but are made of different materials, natural and foreign, which have different levels of impact and construction needs. All of the groups had variability with levels of environmental impact which suggests that certain features may be more harmful to the environment than others. If there are multiple features providing the same experience and one has less environmental impact then management may substitute one feature for another.

Implications This assessment tool has many management implications including site design, social rules and feature management. Proposed mountain bike sites can be designed with trail features that have known environmental, social, safety and managerial components that will increase resource sustainability and user satisfaction. The GPS tool allows management to monitor the safety, condition and number of technical trail features under their control. The geo-tagged photos can also be used to make paper maps or online maps that users can view before riding the trail for the first time (Figure 5).

ReferencesCessford, G. R. (1995). Off-road mountain biking: A profile of riders and their recreation setting and experience preferences. SCIENCE & RESEARCH, (92). Chiu, L., & Kriwoken, L. (2003). Managing recreational mountain biking in wellington park, tasmania, australia. Annals of Leisure Research, 6(4), 339-361.  Davies, C., & Newsome, D. (2009). Mountain bike activity in natural areas: impacts, assessment and implications for management: a case study from John Forrest National Park, Western Australia. Austrailia: Sustainable Tourism. Hollenhorst, S., Schuett, M., Olson, D., & Chavez, D. (1995). An examination of the characteristics, preferences, and attitudes of mountain bike users of the national forests. Journal of park and recreation administration, 13(3), 41-51.  Marion, J., & Wimpey, J. (2007). Environmental impacts of mountain biking: Science review and best practices. In Managing mountain biking: IMBA's guide to providing great riding (pp. 94-111). Boulder, CO: International Mountain Biking Association.Outdoor Foundation. (2009). Outdoor recreation participation report (pp. 1-48). Boulder, CO: Outdoor Foundation. Retrieved from outdoorfoundation.orgPickering, C. (In Press). Environmental, Social and Management Issues of Unauthorised Mountain Bicycling Trail Technical Features in an Australian Peri- urban Forest. Pickering, C. M., Newsome, D., Hill, W., & Leung, Y. (2010). Comparing hiking, mountain biking and horse riding impacts on vegetation and soils in Australia and the United States of America. Journal of environmental management, 91(3), 551-562.  Shimano, & International Mountain Bicycling Association. (2008). Outdoor freedom: As natural as riding a bike. The economic benefits of mountain biking (pp. 1-6).Symmonds, M., Hammit, W., & Quisenberry, V. (2000). Managing Recreational Trial Environments for Mountain Bike User Preferences. Journal of Environmental Management, 25(5), 549-564.  Thurston, E., & Reader, R. (2001). Impacts of experimentally applied mountain biking and hiking on vegetation and soil of a deciduous forest. Environmental management, 27(3), 397.  Webber, P., & International Mountain Bicycling Association. (2007). Managing mountain biking : IMBA's guide to providing great riding. Boulder, COMountain bike picture: www. www.pinedaleonline.com/scr-bikeronlogramp2.jpg

Figure 4: SkinnyFigure 3: Drop-off

Figure 2: Rock Garden

Figure 1: A-frame

Figure 5: Geo-tagged Trail Features

Figure 2

In an effort to understand mountain biking and its' impacts the technical trail features were initially categorized into natural, enhanced and built features. Natural features are technical terrain that provides challenge to the riders but has not been changed by humans. Built enhanced features are features that are comprised of natural, native material but have been moved or changed by humans to provide challenge. Built features are predominately structures that are made of foreign materials that have brought to the site and constructed by humans to provide an element of challenge. Although this categorization has implications for management it was not found to be an effective way to assess technical trail features. Instead a categorization of features based on the experiences they provided was more effective for assessment and future application. Three categories (aerial, ground and traverse) were designed to encompass the physical and mental experiences provided by all technical trail features. Aerial features allow riders to challenge themselves through the air and gravity. Ground features allow riders to manuever technical terrain on the ground. Traverse features allow riders to go from point a to point b on a structure that takes the rider off the natural trail of surface. The challenge presented and skill required can change based on the dimension of the feature but the provided type of experience remains constant.

Statistical Analysis SPSS 18 was used for the statistical analysis of features and categories for the 28 different assessment components. Data trends showed a skew to the right hand side which required data transformations (inverse and log) on several variables. A one-way ANOVA was used to determine variance at the .05 level between the three different experience groups. Due to the low sample size a non-parametric Chi-square analysis was used to examine variance among technical trail features within the experience group.

Table 2: One-way ANOVA for Experience Groups

Table 1: Assessment Variables

Aerial

Ground

Traverse