抄録
To assess influences of light and substrate conditions on Hinoki cypress Chamaecyparis obtuse (Sieb. et Zucc.) Endl. establishment in warm-temperate mixed forest, size structures of canopy trees and tree species composition within a gap formed by uprooting of a canopy tree in 1997 were compared to those under the closed forest in Ichinomata Conservation Forest, Shikoku, Japan. In the study site, Hinoki cypress were dominant in the forest canopy; however, there were no seedings (H＜1.3m) and sapling (GBH＜15cm, H≧1.3ｍ) under the closed canopy. Within the uprooting gap, we found 13 and one individuals of seedlings and saplings, resepectively, The established seedlings, however, were found on stable bare ground but not found on unstable colluvial slope. The existence of seedling and saplings of Hinoki cypress within the gap may be due to the improvement of light condition by gap formation, and removal of litters that prevent seeding establishment. These results suggest that gap formation may contribute for Hinoki cypress establishment, but other factors, such as existence of litters and ground stability, are important as well.
