Distribution characteristics and regeneration opportunities predicted by annual ring analysis of Abies homolepis Sieb. et Zucc. in Oku-Nikko area, Tochigi Pref., central Japan

DOI Web Site 4 Citations 21 References

Bibliographic Information

Other Title
  • 奥日光地域におけるウラジロモミ林の分布特性および年輪解析による更新パターンの予測
  • オクニッコウ チイキ ニ オケル ウラジロモミリン ノ ブンプ トクセイ オヨビ ネンリン カイセキ ニ ヨル コウシン パターン ノ ヨソク

Search this article

Abstract

We investigated distribution characteristics of Abies homolepis forests with aerial photograph analysis and field exploration in the mountainous areas of Oku-Nikko, in central Japan. Abies homolepis was distributed widely in pure stands with high population density, in patch stands and/or mixed stands with low density in the investigated area. They were widely distributed on the southern slope of Mt. Nantai with high density. Its density gradually rose with increasing gradient of the slope. Patch stands of A. homolepis occurred noticeably in the sites of the natural levee and of the flood plain. We analyzed the annual rings to locate the regenerated years of A. homolepis forests and to explain the growth progress made after the regeneration. The analysis presented three types of the annual rings as being normal, with suppressed growth and gaps waiting for growth. All the types showed strong dependency on the light factor of the forest floor. Established ages of seedlings and diameter growth ascertained corresponded with the occurrences of the heavy typhoon attacks in each stand. This phenomenon was remarkable in the event of the typhoons occurred in the middle of 1800's, and in the early and the middle of the 1900's. A. homolepis which might have appeared before the 1800's did not show at investigated years. The age of old-growth forests of A. homolepis in the mountainous areas of Oku-Nikko was estimated as being in the range of 130-160 years old. It might be needed to regenerate for their species existence because of their relatively short life span. The forest decline and canopy release evidenced to have occurred in 1959 caused by Isewan-typhoon was followed by marked acceleration in its regeneration after the typhoon. The general patterns of regeneration in Oku-Nikko area were, therefore, explained from the perspective of canopy release that occurred due to the natural death of A. homolepis and the large-scale collapse of canopy with the events of typhoon, and by their seedling bank on the forest floor. Another and yet critical problem, discovered during the investigation, threatening the survival of the forests, was of the bark tripping done by Sika deer living in Oku-Nikko area We came to be convinced of the need of investigation on the influence of Sika deer exerted on the life of A. homolepis.

Journal

Citations (4)*help

See more

References(21)*help

See more

Details 詳細情報について

Report a problem

Back to top