Imprudent hiking activities raise concerns regarding preservation and management of national parks due to their damaging effects on national parks' surrounding ecosystems and natural·cultural resources. Trail deterioration, especially with its progression, destroys vegetation, and causes damages such as soil erosion and tree roots exposure. Moreover, these damages are currently expanding to surrounding habitats. To settle these concerns, Korean government revised the law related to trails and examined the conditions of trails to establish management programs. However, the examinations and researches are not objective therefore not dependable because they were based on researchers' subjective conclusions, not to mention their limitation to classify detailed standards in evaluating different types of trail deterioration.
Hence, this study selected main trails of each districts in Gyeongju National Park to establish evaluation indicator in order to conduct systemized evaluation standards and evaluated trail deterioration types in Gyeongju National Park. With the results of evaluation, this study aims to identify deteriorated areas and suggest reasonable trail management programs.
Brief explanations of study results are below.
First of all, this study carefully chose 7 research districts from 39 legal trails using purposive selection. Main districts of trail activity, districts with relatively diverse cultural·historical resources and natural landscape components, districts with severe pressure due to easier accessibility, and districts priorly considered for trail restoration were used as deciding factors.
While establishing trail naturalness evaluation, 6 most frequently used standards-trail deepen, trail width expansion, tree roots exposure, divergence, rock exposure, and trail surrounding deterioration-were selected from 17 deterioration types based on analyzation of domestic·international documents. Rating standards-valuation unit of each districts as 50 to 100 meters, and 5 point rating scale-were established based on domestic·international trail evaluation method and preceding studies.
Research results of each districts' trail and naturalness evaluation are as follows:
29 areas were selected from Yongjanggol to Namsan access road (2.3 kilometers) in Namsan district to investigate physical environmental characteristics, and the results showed 1.3 meters of trail width, 1.0 meters of bared trail width, 20.2 centimeters of maximum erosion depth, 11.5 degrees of trail slope, and 31.3 millimeters of soil hardness. 14 types of trail deterioration occurred 87 times and the most frequent deterioration type was rock exposure, which could be observed 24 times (82.8 percent of total deteriorations). This district was rated level Ⅱ in trail naturalness evaluation, indicating relatively well preserved environment of this district. However, several deterioration types appeared in most areas including repaired sections, due to excessive usage pressure of hikers. Rock exposure and trail deepen in particular were rated level Ⅳ, negatively affecting forest environment. For that reason, for sections rated higher than level Ⅳ in trail naturalness evaluation, sections with rock exposure, and trail deepen, comprehensive management program establishment, timely repair of damaged areas, and prevention of further deterioration are a necessity to preserve natural environment.
37 areas were selected from Chooryeong to Tohamsan (2.7 kilometers) in Tohamsan district to investigate physical environmental characteristics, and the results showed 1.1 meters of trail width, 0.9 meters of bared trail width, 13.1 centimeters of maximum erosion depth, 10.8 degrees of trail slope, and 25.7 millimeters of soil hardness. 10 types of trail deterioration occurred 69 times and the most frequent deterioration type was tree roots exposure, which could be observed 17 times (45.9 percent of total deteriorations). This district was rated level Ⅱ in trail naturalness evaluation, and was ranked the second in best preserved districts after Gumisan district. However, area 13 to 30 were rated level Ⅲ in trail naturalness evaluation, indicating relatively severe deterioration within Tohamsan district. Trail deepen, tree roots exposure, and rock exposure types were also highly rated. Consequently, for level Ⅳ areas, establishment of reasonable trail repair program with consistent monitoring is a necessity to repair deteriorated areas and maintain restored trails while preventing further deterioration.
16 areas were selected from Shinseoksa to Danseoksan (2.3 kilometers) in Danseoksan district to investigate physical environmental characteristics, and the results showed 1.9 meters of trail width, 1.9 meters of bared trail width, 33.8 centimeters of maximum erosion depth, 16.35 degrees of trail slope, and 28.9 millimeters of soil hardness. 11 types of trail deterioration occurred 67 times and the most frequent deterioration type was tree roots exposure, which could be observed 14 times (87.5 percent of total deteriorations). This district was rated level Ⅲ in trail naturalness evaluation, and was ranked the second in most damaged districts after Sogeumgangsan district. Areas adjacent to Shinseonsa were rated level Ⅳ to Ⅴ with severe degree of trail deepen, tree roots exposure, and trail width expansion. Trail deepen was rated the highest with level Ⅳ which would negatively affect trail environment by increasing damages in the course of time. Therefore, for areas with level higher than Ⅳ, with the risks of accelerated and extended damages, comprehensive management establishment and trail repair to create pleasant trail environment are a necessity.
40 areas were selected from Yongdamjeong parking lot to Gumisan (2.3 kilometers) in Gumisan district to investigate physical environmental characteristics, and the results showed 0.8 meters of trail width, 0.7 meters of bared trail width, 5.8 centimeters of maximum erosion depth, 12.7 degrees of trail slope, and 25.3 millimeters of soil hardness. 9 types of trail deterioration occurred 71 times and the most frequent deterioration type was trail deepen, which could be observed 15 times (37.5 percent of total deteriorations). This district was rated level Ⅱ in trail naturalness evaluation, which placed this district as the most well preserved. Hence, ecological and environmental conditions of this district were well preserved. However, trail naturalness evaluation results were highly rated in slopes, which would negatively affect trail safety, causing inconvenience for hikers. Therefore, establishment of nature conservation program for level Ⅰ areas is a must, and detailed management program should be arranged to maintain well reserved nature while protecting it from natural·artificial deteriorations.
12 areas were selected from Goolboolsaji to Sogeumgangsan (0.65 kilometers) in Sogeumgangsan district to investigate physical environmental characteristics, and the results showed 5.9 meters of trail width, 3.9 meters of bared trail width, 37.1 centimeters of maximum erosion depth, 16.8 degrees of trail slope, and 34.7 millimeters of soil hardness. 10 types of trail deterioration occurred 65 times and the most frequent deterioration types were trail deepen and divergence, which could be observed 10 times (83.3 percent of total deteriorations). This district was rated level Ⅳ in trail naturalness evaluation, indicating the most damaged trail environment of this district with higher usage pressure compared to other districts. Areas adjacent to Baekryulsa displayed severe deterioration caused by usage pressure from hikers. All types of deterioration in this area were rated level Ⅴ, indicating harshly damaged environment of trail. Trail deepen and tree roots exposure were rated the highest with level Ⅴ, and as a result, growing environment along the ridgeline was unhealthy for pine tree forest. Therefore, establishing comprehensive trail management program for areas with level Ⅳ and higher is a must. Furthermore, to conserve nature and pleasant trail environment, systematic and reasonable management program must be established. For areas with level Ⅴ with the concerns of serious damages, the rest-year sabbatical system must be enforced to regulate hiking for a certain period of time.
18 areas were selected from Gyeongdaegyo to Songhwasan 12.3 kilometers) in Hwarang district to investigate physical environmental characteristics, and the results showed 1.1 meters of trail width, 0.9 meters of bared trail width, 14.2 centimeters of maximum erosion depth, 13.1 degrees of trail slope, and 35.0 millimeters of soil hardness. 11 types of trail deterioration occurred 55 times and the most frequent deterioration type was tree roots exposure, which could be observed 14 times (77.8 percent of total deteriorations). This district was rated level Ⅱ in trail naturalness evaluation with a good rating on trail width expansion, meaning this district was fairly preserved. However, unauthorized arable land and graveyard on the entrance of trail disturbed surrounding ecosystem and greatly damaged forest environment and natural landscape. Trail deepen and tree roots exposure were rated the highest with level Ⅳ, and these deterioration types prevailed in most areas of this district. Therefore, for areas with level Ⅳ and higher with trail deepen, and tree roots exposure, establishment of comprehensive trail management program, timely repair, and prevention of further deterioration are a necessity.
23 areas were selected from Muyeolwangleung to Seondosan (1.6 kilometers) in Seoak district to investigate physical environmental characteristics, and the results showed 1.8 meters of trail width, 1.7 meters of bared trail width, 14.2 centimeters of maximum erosion depth, 12.2 degrees of trail slope, and 30.8 millimeters of soil hardness. 9 types of trail deterioration occurred 74 times and the most frequent deterioration type was trail deepen, which could be observed 18 times (78.3 percent of total deteriorations). This district was rated level Ⅱ in trail naturalness evaluation, which indicted comparatively well preserved trail environment of this district. However, this district was ranked after Sogeumgangsan district and Danseoksan district. Trail width expansion, trail deepen, and trail surrounding deterioration especially were highly rated, meaning relatively damaged trail environment. Furthermore, rock exposure and trail deepen were rated level Ⅳ in trail naturalness evaluation for most of the areas. Therefore, for areas with level Ⅳ and higher, and for rock exposure and trail deepen, establishment of comprehensive trail management program, timely repair of trail, and prevention of further deterioration are a necessity.
Finally, this study can be practically used as basic, all-inclusive database of major trails in Gyeongju National Park when establishing trail management program and comprehensive management program to repair deteriorated trails in time while preventing further deterioration to raise efficiency of natural resources reservation. Additionally, this study can be applied in prioritization of damaged districts using trail naturalness evaluation results as a reference to suggest guidelines for systematic and reasonable management programs classified by each deterioration types.