Changes of Spatio-temporal Distribution of Korean fir Forest in Mt. Hallasan over the Past 100 Years

Changes in the distribution of Korean fir(Abies koreana) forest in Mt. Hallasan from the early 1900s to the present were analyzed using old maps and aerial photographs. In 1918, the area of Korean fir forest was analyzed as 1,168.4ha, and it has continued to decrease since then. The forest area in 2021 was analyzed as 606.0ha, a decrease of 562.4ha compared to 1918, which is a 48.1% decrease over 100 years. The growth decline of Korean fir forest showed differences depending on the times. From the early 1900s to the early 2000s, the average annual decreasing rate was 0.24% to 0.50%, but it rapidly increased to 1.37% to 1.99% after 2006. Forest changes in Mt. Hallasan showed different trends depending on the region. Over the past 100 years, the forest has expanded in the Bangaeoreum area, while it has decreased in the Jindallaeba, Yeongsil, and Keundurewat areas. In particular, the Jindallaeba area has decreased by 60.1% over the past 100 years, showing the largest reduction in distribution. As shown in these results, over the past 100 years, the Korean fir forest in Mt. Hallasan has shown a continuous overall decline, confirming a clear difference in decreasing trend between the 1900s and 2000s, and showing different trends depending on the region. This difference is interpreted as the fact that various growth decline factors cause different artificial or natural intensity of damage depending on the environment of Korean fir forest distribution area.