Forest Recovery Process and Restoration After Large-Scale Disturbances
摘要
In Hokkaido, windstorms including typhoons are major disturbances, notably Typhoon Marie in 1954 and Typhoon Thad in 1981, which caused extensive damage to the University of Tokyo Hokkaido Forest (UTHF). Conifers are more susceptible to wind damage than broadleaves. Post disturbance, the UTHF employed salvage logging and reforestation. Conifer planted stands generally successfully grew up although invaded broadleaves often outcompete planted conifers. Naturally regenerated stands after soil scarification were characterized as Betula species with too high of a density. Naturally regenerated stands without any postdisturbance practices were dominated by mixed conifer-broadleaf forests. Salvage logging also impacts ecosystems by reducing the habitat available for saproxylic organisms and altering carbon stocks. Large-scale human-caused wildfires in the 1910s created a vast area of secondary forests, which are currently dominated by Betula maximowicziana. Some of the Norway spruce plantations established after these fires have also matured into old-growth stands. Snow damage, particularly in young forests, further stress the forest, with wet snow bending or breaking tree stems. Due to climate change, the frequency and severity of these disturbances are expected to increase, prompting the UTHF focus on developing forests that are more robust and resilient to such disturbances.