2024-03-29T05:19:13Zhttps://eprints.lib.hokudai.ac.jp/dspace-oai/requestoai:eprints.lib.hokudai.ac.jp:2115/678112022-11-17T02:08:08Zhdl_2115_20046hdl_2115_138風害後40年間の落葉広葉樹林の林分回復過程と主要樹種の幹数動態Recovering process and dynamics of the number of stems of maior tree species in a deciduous broadleaved forest in 40 years after a large-scale disturbance by a typhoon渋谷, 正人矢島, 崇川合, 由香渡辺, 訓男西川, 功幹数動態固定調査区大規模撹乱落葉広葉樹林林分回復過程deciduous broadleaved standlarge-scale disturbancepermanent plotstand recovering processstemdensity dynamics470抄録:1954年の15号台風により大規模な攪乱を受けた林分に設定された固定調査区(0.25ha)において、風害後40年間の林分の回復過程と、主要樹種の幹数動態について検討した。胸高断面積合計値は風害前の推定値の86%となり、林分レベルでの量的な回復は風害後40年間で進んでいるが、樹種構成やサイズ分布などの質的な面での回復にはまだ長期間が必要と考えられた。風害後に樹種数は増加したが、現在幹数が多い樹種は風害以前と類似していて、林分の回復は風害以前に分布していた樹種が中心となっていた。おもな樹種の風害前後および風害後の幹数動態は樹種によって異なる傾向があり、3タイプに区分された。しかし、それぞれのタイプには、種子による更新特性や耐陰性が異なる樹種が含まれ、このことは大規模攪乱の場合の特徴と考えられた。さらに本調査地では、樹種による萠芽性の違いが幹数動態に影響していると推察され、種子更新以外の更新特性も考慮する必要性が指摘された。Abstract:Stand recovering process and dynamics of the number of stems of major tree species in 40 years after a large-scale disturbance by a typhoon in 1954 were monitored in a permanent plot (0.25 ha) in a deciduous broadleaved stand. The basal area in 1994 was restored to up to 86 % of the estimated basal area before the disturbance, but tree species composition and DBH distribution in 1994 differed from those before the disturbance. Forty years is not considered to be sufficient to reconstruct stand structure and species composition. The number of tree species increased after the disturbance, however, the predominant tree species in 1994 were similar to those before the disturbance and they contributed significantly to stand recovery. Major tree species in 1994 were classified into 3 types, depending on their dynamics of the number of stems through and after the disturbance. It seemed to be a characteristic of stand recovery after a large-scale disturbance that tree species with various behaviors of seed germination and shade tolerance were put together in a given species group in the classification. Since vegetative regeneration, such as sprouting, is assumed to be important in this stand's recovery from the disturbance, regeneration behaviors other than seeding need to be taken into account as regeneration sources of tree species.日本森林学会Journal Articleapplication/pdfhttp://hdl.handle.net/2115/67811https://eprints.lib.hokudai.ac.jp/dspace/bitstream/2115/67811/1/79_195.pdf0021-485X2185-8195日本林学会誌7941952011997jpninfo:doi/10.11519/jjfs1953.79.4_195publisher