Researcher Profile and Settings

Master

Affiliation (Master)

• Research Faculty of Agriculture　Fundamental AgriScience Research　Forest Science

Affiliation (Master)

• Research Faculty of Agriculture　Fundamental AgriScience Research　Forest Science

researchmap

Profile and Settings

Degree

• (BLANK)
• (BLANK)

Profile and Settings

• Name (Japanese)

  Shibuya

• Name (Kana)

  Masato

• Name

  200901023863200090

Achievement

Research Interests

• 生態   林学   Ecology   Forestry   

Research Areas

• Life sciences / Forest science
• Life sciences / Ecology and environmental science

Education

•        - 1985  Hokkaido University
•        - 1985  Hokkaido University  Graduate School, Division of Agriculture
•        - 1982  Hokkaido University  Faculty of Agriculture
•        - 1982  Hokkaido University  Faculty of Agriculture

Published Papers

• Long‐term stand‐level resilience in natural secondary forest stands recovering from severe windthrow damage

  Masato Shibuya

  Ecosphere 12 (9) 2150-8925 2021/09 [Refereed][Not invited]
  
• 北海道の森林の風害と林分管理の考え方

  渋谷正人

  北方林業 71 41 - 44 2020/04 [Refereed][Invited]
  
• カラマツの枝条形成における長枝化と花芽分化の関係

  馬場俊希, 齋藤秀之, 宮本敏澄, 渋谷正人

  北方森林研究 68 53 - 56 2020/02 [Refereed][Not invited]
  
• Stand-level windthrow patterns and long-term dynamics of surviving trees in natural secondary stands after a stand-replacing windthrow event

  Masato Shibuya, Satoshi Ishibashi

  Forestry: An International Journal of Forest Research 92 (4) 473 - 480 0015-752X 2019/10/01 [Refereed][Not invited]
   

  We examined typhoon windthrow patterns in stand-scale permanent plots within three natural forests and the long-term dynamics of surviving trees in two of these plots. The aim was to verify whether pre-disturbance composition and structure affected windthrow damage and stand recovery. The stands, which were in Hokkaido, the northernmost main island of Japan, differed in pre-disturbance composition (coniferous, mixed and broadleaved stands) and structure, and the basal area losses by the windthrow event were 81–93 per cent. Tree mortality was significantly related to tree size (diameter at breast height) and species. The windthrow patterns differed among the three stands; and, windthrow severity was affected by the pre-disturbance composition and structure. The mortality of trees that survived the windthrow event was ~60 per cent in the two plots. The surviving trees comprised a majority of the canopy layer in the secondary stands. The relative basal area of surviving trees decreased rapidly with increasing tree density in the stand initiation stage but differed between plots. Consequently, the pre-disturbance composition and structure influenced windthrow severity, stand recovery and secondary succession in the recovered stands.
• Long-term effects of salvage logging after a catastrophic wind disturbance on forest structure in northern Japan

  Junko Morimoto, Toshihiro Umebayashi, Satoshi Suzuki, Toshiaki Owari, Naoyuki Nishimura, Satoshi Ishibashi, Masato Shibuya, Toshihiko Hara

  Landscape and Ecological Engineering 15 (2) 133 - 141 2019/04 [Refereed][Not invited]
  
• グイマツ雑種F₁苗木の成長に対する踏圧と窒素沈着の影響

  横山聡子, 菅井徹人, 江口則和, 佐藤冬樹, 斎藤秀之, 渋谷正人, 小池孝良

  北方森林研究 (67) 27‐28  2186-7526 2019/02 [Refereed][Not invited]
  
• Stand recovery of a temperate hardwood forest 60years after a stand-replacing windthrow based on a permanent plot study

  Mariko Toda, Masato Shibuya

  JOURNAL OF FOREST RESEARCH 22 (5) 303 - 308 1341-6979 2017 [Refereed][Not invited]
   

  We examined the dynamics of stand structure and composition over a 60-year period in two permanent plots in a deciduous hardwood forest in Hokkaido, Japan, which were severely disturbed by a stand-replacing windthrow, to reveal trends that could be valuable to the development of a model of forest recovery after a severe windthrow. We analyzed temporal trends in tree density, species richness and diversity, successional composition, and stand development stage in the plots. Both plots recovered as hardwood stands. Tree density and species richness increased, peaking 3540years after the windthrow, and then decreased in both plots. Based on these results, we concluded that both plots were in the stand-initiation stage for 3540years after the windthrow and then transitioned into the stem-exclusion stage. Species diversity increased with an increase in species richness during the stand-initiation stage and then decreased slightly in both plots. In both plots, successional composition did not fluctuate greatly in the 60years after the windthrow, and both returned to pre-disturbance composition during the stem-exclusion stage. The temporal trends observed in this study were remarkably similar to those in a previous study of permanent plots located near the plots used in this study. Therefore, this study provides valuable information that can be useful in the development of a stand recovery model in temperate forests after stand-replacing windthrows.
• Sixty-year post-windthrow study of stand dynamics in two natural forests differing in pre-disturbance composition

  Ryota Kosugi, Masato Shibuya, Satoshi Ishibashi

  ECOSPHERE 7 (11) 2150-8925 2016/11 [Refereed][Not invited]
   

  We examined the dynamics of stand structure and composition over 60 years in two natural secondary forest plots in central Hokkaido, Japan, that had been severely disturbed by a stand-replacing windthrow in 1954. We determined temporal trends in tree density, species richness, species diversity, successional composition, and stand developmental stage. One of the plots contained a coniferous stand prior to the disturbance; the second plot contained a mixed stand. Tree density and species richness increased after the windthrow, and peaked in both stands in 1991, 37 years after the windthrow. Based on the dynamics of tree density and species richness, the stand development phase of both plots remained within the stand initiation stage until 1991, and then progressed to the stem exclusion stage by 2014, 60 years after the windthrow. Based on patterns of increasing tree density by species in both plots, vegetative regeneration was presumed to have contributed abundantly to the recovery of the stand after the windthrow. Species diversity increased after the windthrow as species richness increased in both stands; diversities peaked 23 or 32 years after the windthrow and declined slightly thereafter. Although the successional composition of the pre-disturbance coniferous stand regressed to an early stage under the influence of the windthrow, the relative importance of late-successional species approached the pre-disturbance value as the plot recovered. In contrast, the successional composition of the mixed conifer/hardwood plot was unaffected by the windthrow, but gradually changed to an early stage over several decades following the windthrow. The difference in successional composition between plots was likely a result of differences in pre-disturbance stand conditions between stands. Our 60-year permanent plot study determined stand and population dynamics, the duration of the stand initiation stage, and the interrelationships between diversity and species richness. Long-term permanent plot studies contribute crucial data for the interpretation of forest dynamics following disturbance.
• ニホンカラマツとグイマツ雑種F1苗木の光合成能に対するオゾン暴露と硫酸アンモニウム付加の影響

  菅井徹人, 渡部敏裕, 来田和人, 齋藤秀之, 渋谷正人, 小池孝良

  北方森林研究 64 63 - 66 2016/02 [Refereed][Not invited]
  
• Effects of ozone and/or ammonium sulfate on the photosynthesis and growth of Japanese larch and hybrid larch F₁

  Sugai Tetsuto, Watanabe Toshihiro, Kita Kazuhito, Saito Hideyuki, Shibuya Masato, Koike Takayoshi

  The Japanese Forest Society Congress 日本森林学会 127 730 - 730 2016 

  [in Japanese]
• Epigenetic control of Fagus crenata flowering; the relationship between DNA methylation and nutrients

  Wada Hisayuki, Saito Hideyuki, Shibuya Masato, Koike Takayoshi

  The Japanese Forest Society Congress 日本森林学会 127 334 - 334 2016 

  [in Japanese]
• The effects of nitrogen depostion on fine root gowth of Hybrid larch F₁ : A comparison of phosphorus addition

  Fujita Saki, Kita Kazuhito, Saioto Hideyuki, Shibuya Masato, Koike Takayoshi

  The Japanese Forest Society Congress 日本森林学会 127 (0) 742 - 742 2016 [Refereed][Not invited]
   

  [in Japanese]
• Comparable benefits of land sparing and sharing indicated by bird responses to stand-level plantation intensity in Hokkaido, northern Japan

  Chiaki Yoshii, Yuichi Yamaura, Masashi Soga, Masato Shibuya, Futoshi Nakamura

  JOURNAL OF FOREST RESEARCH 20 (1) 167 - 174 1341-6979 2015/02 [Refereed][Not invited]
   

  We examined potentially contrasting conservation benefits of land sparing (land-use specialization) and land sharing (multiple-use forestry) strategies in forested landscapes by investigating relationships between bird functional group densities and basal areas of coniferous trees (an index of plantation intensity) in Sakhalin fir (Abies sachalinensis) and Sakhalin spruce (Picea glehnii) plantations. Densities of most bird functional groups increased with decreasing plantation intensity in both plantation types. In many cases, linear models were best for descriptors of bird density-plantation intensity relationships, but statistical support of linear and nonlinear (quadratic) models was similar. This outcome indicates that ecological benefits of land sparing and land sharing are potentially comparable in the plantations we studied. In real landscapes, land-use decision making depends on a variety of factors other than biodiversity conservation (e.g., social and biophysical factors). Furthermore, niche theory also predicts that population densities could linearly respond to environmental gradients. When density-intensity relationships are linear, as in this study, land-sparing and land-sharing strategies provide similar benefits in terms of biodiversity conservation, and contrasting land-use strategies could be flexibly chosen to enhance the accommodation of biodiversity conservation to resource production.
• Tropical peatland forestry: Toward forest restoration and sustainable use of wood resources in degraded peatland

  Hideyuki Saito, Akio Koizumi, Sampang Gaman, Prawira Yuda, Penyang, Masato Shibuya

  Tropical Peatland Ecosystems 513 - 549 2015/01/01 [Refereed][Not invited]
   

  Forestry is an important land-use type in tropical peatlands that provides socio-economic and environmental services. Currently, tropical peatland forestry has contributed to the timber industry, but timber harvest has unfortunately caused degradation and deforestation in massive areas of tropical peat swamp forests. Consequently, serious reductions of wood resources and environmental services occurred in peatland forests, with land managers being caught in a forest management dilemma between the needs for timber production, conservation and restoration of environmental services. The woody materials produced from peatland forests have various and unique characteristics these forests also provide commercially valuable timber. Given that degraded peatland can be restored to forest composed of indigenous trees of high ecological and commercial value, land managers feel confident that they can provide the benefits of both timber production and improved environmental services. First, during planting one must understand which tree species are best adapted to local site-conditions if successful reforestation techniques are to be developed. Cost-effectiveness must also be concerned, especially in degraded peatland, where considerable flooding may determine the survival and growth rates of seedlings and the operating cost. Second, as a management strategy, a reforestation program should be required to provide multiple benefits, not only timber production and environmental services, but these programs should also improve socio-economic conditions that ensure the ongoing livelihood of local people. In the future, tropical peatland forestry should play the roles of providing for both the restoration and sustainable use of wood resources in a way that benefits both the local community and the global market.
• Effect of charcoal and fallen-leaves of black locust on water relations of black pine seedlings

  Watanabe Hanami, Fujita Saki, Meng Fakeng, Tamai Yutaka, Saito Hideyuki, shibuya Masato, Koike Takayoshi

  The Japanese Forest Society Congress 日本森林学会 126 (0) 255 - 255 2015 [Refereed][Not invited]
   

  [in Japanese]
• 窒素沈着がダケカンバとシラカンバの成長と外生菌根の発達に与える影響

  木基二, 渡辺誠, 斎藤秀之, 渋谷正人, 玉井裕, 小池孝良

  北方森林研究 62 65 - 66 2014/02 [Refereed][Not invited]
  
• The effect of forest-thinning works on tree growth and forest environment

  Jeong-Seok Kang, Masato Shibuya, Chang-Seob Shin

  Forest Science and Technology 10 (1) 33 - 39 2158-0103 2014/01 [Refereed][Not invited]
   

  This research was conducted to provide effective forest management through forest tree production and forest land changes which took place after the forest-tending works in the plantation of Pinus koraiensis. It has been shown that the current annual diameter growth of trees in regions which implemented forest-tending projects in 2005 had increased by 142.9% compared to those which did not implement the forest-tending projects. In 2006, the current annual diameter growth of trees in implemented regions increased by 132.6% compared to those which did not implement forest-tending. Additionally, in the Pinus koraiensis plantation of II-III age classes where forest-tending projects works were implemented, the growth in diameter started to show a clear increase in the year following the implementation, and the maximum effects were displayed within 3-5 years. Thereafter, the growth gradually started to slow down. Therefore, implementing forest-tending works repetitively with a minimum period of 5 years would be considered appropriate. Soil moisture during the rainy season did not show significant differences as the soil moisture content remained at 40.4-43.0%. However, during the dry season, regions which did not implement forest-tending showed an average of 20.4%, and regions which implemented forest-tending showed an average of 26.6%, and the differences were greater when compared to the rainy season. Due to the control in the density of the number of forest trees due to forest-tending and forest thinning works, the number of understory woody plant species increased from 17 to 30 and the number of herbaceous plant species increased from 20to 44. Furthermore, as the density of standing trees was reduced to about 50% in places where forest-tending works were implemented, crown length ratios increased greatly from 46.1% to 62.1% and became a great help to the growth of forest trees. © 2014 © 2014 Korean Forest Society.
• Both stem and crown mass affect tree resistance to uprooting

  Tsutomu Urata, Masato Shibuya, Akio Koizumi, Hiroyuki Torita, JooYoung Cha

  JOURNAL OF FOREST RESEARCH 17 (1) 65 - 71 1341-6979 2012/02 [Refereed][Not invited]
   

  To examine the hypothesis that both stem and crown mass affect the resistance of a tree to uprooting and that tree resistance increases with increasing crown mass, we conducted tree-pulling experiments on three Picea glehnii plantations (stands A, B, and C: 27-32 years old) that differed in tree density and slenderness ratio. Allometries between crown and stem masses and between the critical uprooting moment and stem mass differed significantly among the three stands, with the crown mass and critical moment significantly larger in stand C than in stands A or B, despite the same stem mass. These results quantitatively verified our hypothesis. Allometries between crown and stem masses and between critical uprooting moment and stem mass were highly significant in each stand but were stand specific. Therefore, these allometries can be used to estimate tree resistance to uprooting in a given stand but not for data compiled from stands of various conditions and tree shapes. The allometry between critical moment and aboveground mass did not differ among the three Picea stands; thus, it is not stand specific and is generally appropriate to use for estimating tree resistance. To increase tree resistance to uprooting, we recommend light management for Picea glehnii plantations and probably other coniferous plantations as well.
• Site preference and occurrence patterns of Picea jezoensis and Abies sachalinensis on decayed logs in natural coniferous forests in Hokkaido, northern Japan

  Keisuke Yano, Masato Shibuya

  JOURNAL OF FOREST RESEARCH 15 (2) 108 - 114 1341-6979 2010/04 [Refereed][Not invited]
   

  The objectives of this study were to investigate differences in the site preferences of seedlings of Picea jezoensis and Abies sachalinensis on decayed logs, and to examine the occurrence patterns of seedlings and saplings of the two species and whether they occur together or separately on logs. We characterized the habitats of 1-2-year-old seedlings of the two species on logs and examined the relationship of the two species on logs by growth stages in two plots. One plot had been disturbed about 50 years ago whereas the other had not for a long time. Although the thickness of moss and the litter layer in the habitats of 1-2-year-old seedlings were significantly different between the two species, the two species could occur together. In one study plot, seedlings and saplings of the two species occurred together. The initial occurrence pattern of the seedlings affected the occurrence patterns of the saplings on logs. The occurrence patterns of the seedlings and saplings of the two species on logs seemed to be affected by the abundance of seed trees. In the other study plot saplings of the two species occurred separately, but one species was not always competitively superior to the other species. Disturbance history affected the occurrence patterns of the saplings of the two species on decayed logs at the two study plots. Consequently, it is concluded that seed dispersal and the abundance of available logs, which are usually affected by disturbance, are significant factors in the natural regeneration of conifers in Hokkaido.
• Evaluation of suitable conditions for natural regeneration of Picea jezoensis on fallen logs

  Hayato Iijima, Masato Shibuya

  JOURNAL OF FOREST RESEARCH 15 (1) 46 - 54 1341-6979 2010/02 [Refereed][Not invited]
   

  The abundance of Picea jezoensis, a major conifer tree species in Hokkaido, northern Japan, is currently decreasing due to the lack of suitable conditions for recruitment and intensive harvests. To contribute to the development of sustainable forest management in Hokkaido, suitable substrates for natural regeneration of P. jezoensis were evaluated during a 4-year experimental study using seed additions in a natural coniferous forest. The environmental conditions (moss height, log hardness, extent of the humus layer, and light conditions) of fallen logs were measured. Moss height was categorized into three groups: 0 mm, Bark; 0-20 mm, Mthin; and a parts per thousand yen20 mm, Mthick. The germination rates of P. jezoensis were highest on Mthin, intermediate on Bark, and lowest on Mthick. Survival rates were low on Mthick, did not differ between Bark and Mthin, and increased with enhanced light. Growth increased with light, but the root allocation of seedlings was not affected by any environmental conditions. From these results, we determined that fallen logs with no or thin moss cover under bright conditions were most suitable for P. jezoensis regeneration. We discuss the generality of our results in relation to a co-occurring tree species in Hokkaido and the results of other regions.
• Wind damage prediction in Japanese larch stands using a mechanistic model

  TORITA Hiroyuki, SHIBUYA Masato, KOIZUMI Akio

  Journal of the Japanese Forest Society 日本森林学会 92 (3) 127 - 133 1349-8509 2010 [Refereed][Not invited]
   

  It is important to be able to assess the risk of wind damage to stands in a long rotation forestry operation. In this study a mechanistic model was used to examine the effect of different planting densities and thinning frequencies on the resistance of Japanese larch stands to wind damage. Critical wind speeds at a height of 10 m above ground level required to cause uprooting or stem breakage was used as the index of resistance to wind damage. All wind damage to trees was uprooting. The resistance of stands at lower planting densities was higher than that of stands at higher planting densities. Differences in thinning frequency affected stand resistance: management for a low yield index (Ry=0.6∼0.7) increased the resistance of stands compared with management for a high yield index (Ry=0.7∼0.8). As stand age increased, resistance to wind damage decreased until a tree was 20∼30 years of age. Thereafter, resistance to wind damage increased as stand age increased. This 20- to 30-year period coincided with the period during which slenderness ratios (H/D) were the highest of all growing stages. Differences in a long rotation forestry operation at high site index had a strong effect on the resistance to wind damage.
• Analysis of windthrow factors in Windbreaks: In the central Bibai, Hokkaido by typhoon No. 18 in 2004

  SHIBUYA Masato

  Journal of the Japanese Forest Society 一般社団法人日本森林学会 91 (5) 307 - 312 1349-8509 2009 [Refereed][Not invited]
   

  Windthrow factors in windbreaks in Bibai, Hokkaido, which was damaged by typhoon No. 18 (max wind speed 21m/s) in 2004, were analyzed. The windbreaks investigated were plantations of Picea abies, Larix leptolepis, Betula platyphylla, or Fraxinus mandshurica. Diameter at breast height (DBH) and the type of damage (e.g., "uprooted", "snapped", or "undamaged") were determined for each tree in 21 quadrats. The vertical profile of soil hardness was also measured using a simplified dynamic cone penetrometer in each quadrat. The maximum moment of resistance against uprooting was measured by pulling the trunk of a standing tree laterally for each species to determine why the sensitivity to windthrow differed. The sensitivity to windthrow decreased in the order L. leptolepis>P. abies>B. platyphylla>F. mandshurica. The sensitivity to windthrow had a bell-shaped distribution with a peak at DBH=30cm. L. leptolepis and B. platyphylla were more likely to be "uprooted", while P. abies was more likely to be "snapped". Soil hardness was not closely related to the sensitivity to windthrow. The moment of resistance against uprooting was higher for F. mandshurica than for the other three species. The sensitivity to windthrow might be related to tree height and leaf mass, in addition to the moment of resistance against uprooting.
• Examination of the coexistence mechanism of two major conifers in Hokkaido, northern Japan, based on differences in suitable germination conditions and shade tolerance

  Hayato Iijima, Masato Shibuya, Hideyuki Saito

  ECOSCIENCE 16 (3) 352 - 360 1195-6860 2009 [Refereed][Not invited]
   

  The coexistence mechanism of Abies sachalinensis and Picea jezoensis, which usually regenerate on fallen logs, was examined with respect to differences in suitable conditions for germination and shade tolerance in Hokkaido, northern Japan. Germination conditions were evaluated through the effect of log hardness, moss height, light condition, and shading by taller seedlings on fallen logs, and shade tolerance was evaluated by physiological and morphological traits and survival dynamics in a natural coniferous forest. In contrast to P. jezoensis, the number of germinated seedlings of A. sachalinensis increased with moss height. The number of germinated seedlings decreased with shading only in P. jezoensis. Consequently, it is suggested that germination of P. jezoensis is limited to fresh, recently fallen logs. The survival rate of A. sachalinensis under low-light conditions (< 5% of relative photosynthetic photon flux density) was higher than that of P. jezoensis. Abies sachalinensis had a higher leaf mass ratio (total leaf mass/total mass) and leaf area ratio (total leaf area/total mass) than P. jezoensis. In conclusion, earlier establishment of P. jezoensis on fallen logs and higher shade tolerance of A. sachalinensis are suggested to contribute to the coexistence of these 2 species.
• Invasion and growth processes of natural broadleaved trees and influences of thinning on the processes in an Abies sachalinensis plantation

  NONODA Shuichi, SHIBUYA Masato, SAITO Hideyuki, ISHIBASHI Satoshi, TAKAHASHI Masayoshi

  Journal of the Japanese Forest Society 一般社団法人日本森林学会 90 (2) 103 - 110 1349-8509 2008 [Refereed][Not invited]
   

  To determine the invasion and growth processes of natural broadleaved trees in a conifer plantation, and to examine the influence of forest operations on these processes, we investigated the species composition, the number of annual rings at 0.3 m from the ground and annual diameter increments of natural broadleaved trees in an 80-year-old Abies sachalinensis plantation in Hokkaido, northern Japan. Species number and the density of broadleaved trees increased after thinning. The frequency of the number of annual rings at 0.3 m from the ground was apparently high in years following thinnings, except for the first thinning. Therefore, plantation thinning induced natural invasion of broadleaved trees. Furthermore, the diameter increments of many broadleaved trees apparently increased after thinning. Thinning positively influenced the growth of broadleaved trees in the plantation. Mean annual diameter increments differed between late-successional and gap-phase species. The mean diameter increment and increases in the increment after a thinning were larger in gap-phase species than in late-successional species. Additionally, the individual ratio and frequency of apparent increases in diameter increments after thinning were larger in older broadleaved trees. Consequently, we conclude that age and ecological characteristics of broadleaved trees in an Abies sachalinensis plantation influence their growth and the influence of thinning on growth.
• The stress responses and seasonal changes of gene expressions for photosynthesis, active oxygen scaving and senescence induction in leaves of Fagus crenata tree crown

  Yamada Tadayasu, Hayashi Toshiro, Saito Hideyuki, Shibuya Masato

  The Japanese Forest Society Congress 日本森林学会 118 109 - 109 2007
• Initial screening of fast-growing tree species that can tolerate dry tropical peatlands in Central Kalimantan, Indonesia.

  Saito H, Shibuya M, Tuah SJ, Turjaman M, Takahashi K, Jamal Y, Segah H, Putir PE, Limin SH

  Journal of Forestry Research 2 107 - 115 2005 [Refereed][Not invited]
  
• 北海道は森林国?

  渋谷 正人

  森林科学 : 日本林学会会報 日本森林学会 31 66 - 67 0917-1908 2001/02/01
• Chronosequential analysis of aboveground biomass and the carbon and nitrogen contents in natural Larix stands in eastern Siberia

  Shibuya M, Tsuno Y, Saito H, Takahashi K, Sawamoto T, Hatano R, Isaev AP, Maximov TC

  Bulletin of Research Center for North Eurasia and North Pacific Regions, Hokkaido, University 1 57 - 66 2001 [Not refereed][Not invited]
  
• Aboveground biomass, nitrogen and carbon contents in Larix stands in eastern Siberia

  Tsuno Y, Shibuya M, Saito H, Takahashi K, Sawamoto T, Hatano R, Isaev AP, Maximov TC

  Proceedings of the ninthe symposium on the joint Siberian permafrost studies between Japan and Russia in 2000 68 - 74 2001 [Not refereed][Not invited]
  
• Characteristics of Nitrogen cycling in permafrost regional ecosystems in Yakutsk, Russia

  Hatano R, Sawamoto T, Shibuya M, Saito H, Tuno Y, Takahashi K, Kobayashi Y, Iwahana G, Desyatkin RV, Isaev AP

  Proceedings of the ninthe symposium on the joint Siberian permafrost studies between Japan and Russia in 2000 99 - 103 2001 [Not refereed][Not invited]
  
• Effect of forest fire on NEP in Taiga soil ecosystems, near Yakutsk, Russia

  Sawamoto T, Hatano R, Shibuya M, Saito H, Tuno Y, Takahashi K, Isaev AP, Desyatkin RV, Maximov TC

  Proceedings of the ninthe symposium on the joint Siberian permafrost studies between Japan and Russia in 2000 120 - 127 2001 [Not refereed][Not invited]
  
• Characteristics of ground vegetation at Nelegar Alas

  Takahashi K, Hatano R, Shibuya M, Sawamoto T, Yamamoto G, Tsuno Y, Isaev AP, Maximov TC

  Proceedings of the eighth symposium on the joint Siberian permafrost studies between Japan and Russia in 1999 77 - 82 2000 [Not refereed][Not invited]
  
• Effect of forest fire on physico-chemical properties of Taiga permafrost soils, near Yakutsk

  Hatano R, Sawamoto T, Desyatkin RM, Isaev AP, Takahashi K, Shibuya M, Maximov TC

  Proceedings of the eighth symposium on the joint Siberian permafrost studies between Japan and Russia in 1999 111 - 120 2000 [Not refereed][Not invited]
  
• Effect of forest fire on carbon cycling in Taiga soil-plant system, near Yakutsk

  Sawamoto T, Hatano R, Shibuya M, Takahashi K, Isaev AP, Maximov TC

  Proceedings of the eighth symposium on the joint Siberian permafrost studies between Japan and Russia in 1999 230 - 236 2000 [Not refereed][Not invited]
  
• Allometry and biomass in a 22-year-old stand of Larix cajanderi in eastern Siberia

  Shibuya M, Sugiura T, Takahashi K, Sawamoto T, Hatano R, Cha JY, Fukuyama K, Isaev AP, Maximov TC

  Proceedings of the seventh symposium on the joint Siberian permafrost studies between Japan and Russia in 1998 25 - 32 1999 [Not refereed][Not invited]
  
• Soil respiration and fluxes of N2O and CH4 in Siberian-Taiga ecosystems with different histories of forest fire

  Sawamoto T, Hatano R, Takahashi K, Shibuya M, Isaev AP, Desyatkin RM, Maximov TC, Ivanov BI

  Proceedings of the seventh symposium on the joint Siberian permafrost studies between Japan and Russia in 1998 77 - 89 1999 [Not refereed][Not invited]
  
• Forest Recovery after Disturbance by the 1926 Mudflow at Mount Tokachi, Hokkaido, Japan

  Yajima Takashi, Nakamura Futoshi, Shimizu Osamu, Shibuya Masato

  Research bulletins of the College Experiment Forests, Hokkaido University 北海道大学 55 (1) 216 - 228 0367-6129 1998 [Refereed][Not invited]
  
• The possibility of revegetation based on the amount of dispersed and buried seeds in a site heavily used by sika deer

  YAMAGUCHI Shin-ichi, YAJIMA Takashi, SHIBUYA Masato, TAKAHASHI Kunihide

  Japanese Journal of Forest Environment 森林立地学会 39 (2) 94 - 100 0388-8673 1997 

  The survival of tree seedlings and the amount of dispersed and buried seeds were surveyed. Also, the possibility of plant recovery was discussed on the nearly bare site; which is the result of browsing and trampling by sika deer (Cervus nippon yezoensis) in the broad-leaved stands of Nakanoshima Island, Hokkaido. Tree seedlings disappeared by 70-90% in first twenty days of observation and by 90% within fifty days in all plots. Browsing was the most serious factor, causing more than 80% of seedling damage. The number of dispersed seeds was 238-5,820/m^2 and 21-394/m^2 in 1995 and 1996, respectively. The number of seed species was 11-22 and 7-19 in 1995 and 1996, respectively. A considerable number of viable buried seeds were found, 50-2,700/m^2, and they were composed of 8-20 plant species. Both dispersed and buried seeds contained a large percentage of woody plant species. The number of buried seeds, the number of species and the ratio of viable seeds varied among the study sites, and there were no clear differences between open sites and sites in which the deer were excluded by enclosures. Therefore, the trampling of the forest floor by sika deer did not greatly influence the survival of buried seeds. According to the results of this study, plant recovery is difficult under heavy use by sika deer, however, potential revegetation appears to be possible, for the present.

MISC

• 開放系オゾン付加施設に生育させたハルニレ苗の生理応答:虫害に注目して

  岡本昇太, 齋藤秀之, 渋谷正人, 小池孝良  北方森林研究  (66)  63‐64  2018/02/28  [Not refereed][Not invited]
  
• カラマツコンテナ苗の成長に及ぼす水分環境の影響

  西井あす香, 菅井徹人, 玉井裕, 斎藤秀之, 澁谷正人, 小池孝良  北方森林研究  (66)  27‐30  2018/02/28  [Not refereed][Not invited]
  
• 塩類化土壌とオゾン暴露に対するカラマツ属3種苗木の生理応答~クロロフィル蛍光応答に着目して~

  坪奈津美, WANG Yannan, 菅井徹人, 渡部敏裕, 斎藤秀之, 澁谷正人, 小池孝良  北方森林研究  (66)  55‐57  2018/02/28  [Not refereed][Not invited]
  
• BVOC emissions from leaves of young Japanese white birch under high ozone concentration with special reference to feeding preference of the leaf beetle (Agelastica coerulea)

  増井 昇, 望月 智貴, 谷 晃, 斎藤 秀之, 渋谷 正人, 小池 孝良  北方森林研究 = Boreal forest research  (65)  23  -25  2017/02
• International Journalから 前生林の樹種構成が異なる天然林の風害後60年間の林分動態

  渋谷 正人, 石橋 聰  北方林業 = Northern forestry, Japan  68-  (2)  76  -79  2017
• 異なるO3濃度及び土壌条件下で生育した落葉広葉樹稚樹の虫害．

  井上航, Vanderstock A, 崎川哲一, 中村誠宏, 齊藤秀之, 渋谷正人, 小池孝良  北方森林研究  64-  41  -43  2016  [Not refereed][Not invited]
  
• Stand conditions of middle-aged Larix kaempferi plantations in Tokachi region and a management guideline for long rotation management

  岩﨑 ちひろ, 渋谷 正人, 石橋 聰, 高橋 正義  北海道大学演習林研究報告 = Research bulletin of the Hokkaido University Forests  70-  (1)  21  -30  2015/03  

  カラマツ人工林の長伐期施業に必要な条件を検討するため、北海道十勝地方の54～80年生のカラマツ人工林20林分で林相の特徴を把握した。また、長伐期化する林分に重要な風害抵抗性に着目し、耐風性の指標としてよく用いられる形状比と樹冠長率を検討した。その結果、密度や蓄積、収量比数が小さく、疎仕立て状の林分が多かった。平均形状比は68～90、平均樹冠長率は0.42～0.62であった。既存研究で風害抵抗性が高いカラマツ人工林は、平均形状比が70未満、平均樹冠長率が0.45以上とされているが、本研究の結果では、樹冠長率は既往の値と一致したが、形状比は一致しなかった。このことから、樹冠長率は風害抵抗性を指標する樹形要素として汎用性が高い可能性があると考えられ、その場合平均樹冠長率が0.45以上であることがカラマツの長伐期林に必要な条件と仮定された。そこで、この仮定に基づいて平均樹冠長率0.45以上を維持する密度管理方法を検討した。その結果、I等地では、収量比数を25年生時に0.8以下、30年生以上では0.6未満で管理する必要があり、また林齢にともなって、さらに収量比数を小さく疎な状態に維持しなければならないことが明らかとなった。
• Thinning effect on tree growth in secondary Betula ermanii stands on scarified sites

  SANO Yuuki, SHIBUYA Masato  Journal of the Japanese Forest Society  97-  25  -29  2015  [Refereed][Not invited]
  
• トドマツ人工林における林業機械による根系の損傷と腐朽

  戸田 真理子, 渋谷 正人  北方林業 = Northern forestry, Japan  66-  (8)  229  -232  2014/08
• 大規模風害後の針広混交林の林分動態

  小杉 陵太, 渋谷 正人  北方林業 = Northern forestry, Japan  66-  (8)  225  -228  2014/08
• 開放系オゾン暴露施設で生育したシラカンバ幼木の葉の動態と被食防衛能

  SAKIKAWA TETSUICHI, OIKAWA MONTA, WATANABE MAKOTO, SAITO HIDEYUKI, SHIBUYA MASATO, KOIKE TAKAYOSHI  日本森林学会大会学術講演集(CD-ROM)  125th-  172  2014/03/26  [Not refereed][Not invited]
  
• Tree Shape and Resistance to Uprooting : A Simple Model Analysis

  Shibuya Masato, Koizumi Akio, Torita Hiroyuki  Eurasian Journal of Forest Research  17-  (1)  11  -17  2014  

  We examined tree resistance to uprooting in relation to tree shape using a simple, qualitative model forthe ratio of the resistive moment to the overturning moment. For this analysis, we used model trees andvaried the crown size for a fixed stem size for a ratio of crown mass to stem mass that varied from 0.1to 1. The results predicted the phase transition in the resistance trend in relation to the crownmass/stem mass ratio. Resistance increased on both sides of the crown mass/stem mass ratio, and wasminimized at intermediate ratios. This indicates that crown expansion contributes to resistance to theright side of minimum, and vice versa. The same trend was recognized for actual Sitka spruce tree data.These results were consistent with previous observations of tree resistance to uprooting: trees with asmall slenderness ratio (ratio of height to diameter at breast height) are resistant to uprooting, andtrees/stands are vulnerable to uprooting after thinning, especially after belated thinning. Werecommend sparse tree densities in plantations to manage the risk of physical tree damage such asoverturning and stem failure. However, quantitative analyses of wind damage to trees and stands arenecessary to improve risk management of plantations. The results of this study can be incorporated intosuch quantitative analyses.
• 針葉樹人工林の資源の保続のために (人工林特集)

  渋谷 正人  北方林業 = Northern forestry, Japan  65-  (11)  327  -330  2013/11
• Management guidelines for reducing windthrow damage in Abies sachalinensis and Larix kaempferi plantations

  浦田 格, 渋谷 正人, 鳥田 宏行  北海道大学演習林研究報告  69-  (1)  1  -10  2013/01  

  北海道中央部の支笏湖周辺の平坦地に位置するトドマツ人工林とカラマツ人工林を対象に、林分の平均形状比を用いて、風倒被害を軽減するための林分管理指針を検討した。林分調査データと、各樹種の林分密度管理図を利用して、平均形状比－平均樹高関係を収量比数(Ry)ごとに求め、それらと調査林分の平均形状比を比較した。その結果、両樹種で、風倒被害林分と無被害林分でRy値に差があり、被害林分でRy値が大きかった。境界値はトドマツでRy=0.7で、カラマツでRy=0.4であった。この結果と林分密度管理図によって、風倒被害を軽減するための林分管理指針を、樹種ごとに検討した。その管理指針によれば、風倒被害を軽減するためには若齢時からの密度管理が重要であり、またトドマツ、カラマツ人工林の一般的な疎仕立て管理よりさらに低密度での管理が必要であることが明らかとなった。さらに調査対象地域は風害を受けやすい地域であるため、本研究で検討した管理指針は、北海道の他地域の平坦地にも適用可能であろうと考えられた。
• ブナにおける花芽形成の日長誘導経路に関わる遺伝子群の発現特性

  小倉俊治, 斎藤秀之, 門松昌彦, 渋谷正人, 小池孝良  日本森林学会大会学術講演集(CD−ROM)  123rd-  ROMBUNNO.PB195  -Pb195  2012/03/26  [Not refereed][Not invited]
  
• 摩周湖外輪山におけるダケカンバの衰退現象と立地の関係

  佐久間彬, 渡辺誠, 渡邊忠, 若松歩, 斎藤秀之, 澁谷正人, 小池孝良  日本森林学会大会学術講演集(CD−ROM)  123rd-  ROMBUNNO.J09  2012/03/26  [Not refereed][Not invited]
  
• Capability necessary to Japanese foresters and forest management planners

  SHIBUYA Masato  Boreal forest research  (60)  1  -2  2012/02/18
• Dynamics of shoots of 3 kinds of birch species grown under free air CO_2 enrichment (FACE) system : The results of second year

  HARA Yuko, ITO Hirotaka, MAO Quao-zhi, WATANABE Makoto, HOSHIKA Yasutomo, TAKAGI Kentaro, SAITO Hideyuki, SHIBUYA Masato, KOIKE Takayoshi  Boreal forest research  60-  (60)  39  -40  2012/02/18  [Not refereed][Not invited]
  
• Effects of soil conditions and/or terrain conditions on the forest decline of Betula ermanii at Lake Mashu somma

  SAKUMA Akira, YAMAGUCHI Takashi, NOGUCHI Izumi, WATANABE Tadashi, WAKAMATSU Ayumu, WATANABE Makoto, SAITO Hideyuki, SHIBUYA Masato, KOIKE Takayoshi  Boreal forest research  60-  (60)  43  -44  2012/02/18  [Not refereed][Not invited]
  
• Survivorships of insect herbivores with different food habit on deciduous broad-leaved trees

  OIKAWA Monta, MATSUKI Sawako, SAITO Hideyuki, SHIBUYA Masato, KOIKE Takayoshi  Boreal forest research  60-  (60)  111  -112  2012/02/18  [Not refereed][Not invited]
  
• インドネシア熱帯泥炭湿地の造林樹種Dyera lowiiの育苗における適切な被陰と灌水条件

  稲田友弥, 斎藤秀之, 渋谷正人, 小池孝良, 井上京, HARSANTO Fransiskus A, GAMAN Sampang, PRAWIRA Yuda, LIMIN Suwido H  日本森林学会大会学術講演集(CD−ROM)  122nd-  ROMBUNNO.PA1-13  2011/03/25  [Not refereed][Not invited]
  
• 落葉広葉樹を餌とした食性の異なる植食性昆虫の生残と成長

  及川聞多, 斎藤秀之, 澁谷正人, 小池孝良  日本森林学会大会学術講演集(CD−ROM)  122nd-  ROMBUNNO.PA2-111  2011/03/25  [Not refereed][Not invited]
  
• FACE(開放系大気CO₂増加)施設で育成中のカバノキ属3種の葉の生物季節

  伊藤寛剛, 渡辺誠, 渡辺誠, 毛巧芝, 中路達郎, 笹賀一郎, 斎藤秀之, 渋谷正人, 小池孝良  日本森林学会大会学術講演集(CD−ROM)  122nd-  ROMBUNNO.PB2-73  2011/03/25  [Not refereed][Not invited]
  
• 熱帯泥炭湿地における造林樹種Shorea balangeranの野火耐性

  小出智也, 斎藤秀之, 井上京, 小池孝良, 渋谷正人, GAMAN Sampang, YUDA Prawira, LIMIN Suwido  日本森林学会大会学術講演集(CD−ROM)  122nd-  ROMBUNNO.PA1-33  2011/03/25  [Not refereed][Not invited]
  
• 開放系大気CO2増加(FACE)施設に生育するカンバ類3種の葉のフェノロジー

  伊藤寛剛, 渡辺誠, 渡辺誠, 毛巧芝, 斎藤秀之, 渋谷正人, 笹賀一郎, 小池孝良  日本生態学会大会講演要旨集  58th-  466  2011/03/08  [Not refereed][Not invited]
  
• 高CO2および高O3がカンバ類3種の成長と光合成に与える影響

  稲田直輝, 渡辺誠, 渡辺誠, 澁谷正人, 斎藤秀之, 小池孝良  日本生態学会大会講演要旨集  58th-  464  2011/03/08  [Not refereed][Not invited]
  
• Shoot dynamics of 3 birch seedlings grown under a Free Air CO_2 Enrichment system

  ITO Hirotaka, WATANABE Makoto, MAO Qiao-zhi, NOVRIYANTI Eka, UEDA Tatsushiro, TAKAGI Kentaro, SASA Kaichiro, SAITO Hideyuki, SHIBUYA Masato, KOIKE Takayoshi  日本森林学会北海道支部論文集  59-  (59)  35  -38  2011/02/19  [Not refereed][Not invited]
  
• The growth of three kinds of Betula species grown under elevated CO_2 and/or O_3

  INADA Naoki, WATANABE Makoto, SAITO Hideyuki, SHIBUYA Masato, KOIKE Takayoshi  日本森林学会北海道支部論文集  59-  (59)  41  -44  2011/02/19  [Not refereed][Not invited]
  
• Windthrow damage and tree shape in coniferous plantations in central Hokkaido, northern Japan

  SHIBUYA Masato, URATA Tsutomu, TORITA Hiroyuki, IIJIMA Hayato  Japanese Journal of Forest Environment  53-  (2)  53  -59  2011  [Refereed][Not invited]
   

  We investigated the relationship between windthrow damage and tree shape in coniferous plantations that had suffered windthrow in 2004 in central Hokkaido, northern Japan, to examine the effect of tree shape on the resistance of trees and stands to windthrow. We investigated the following tree-shape parameters in damaged and undamaged plantations of Larix kaempferi, Abies sachalinensis, and Picea jezoensis, major plantation species in Hokkaido, 2-4 years after the windthrow: slenderness ratio (H/D ratio), crown length/tree height ratio (C_L ratio), and the height of the center of gravity of the wind load/tree height ratio (H_W ratio). In L. kaempferi and A. sachalinensis plantations, mean H/D ratios were distinct between damaged and undamaged plantations; the mean H/D ratio was lower in undamaged plantations than in damaged plantations. Based on differences in C_L and H_W ratios, the crown size of L. kaempferi and A. sachalinensis trees was larger in undamaged plantations than in damaged plantations. In P. jezoensis plantations, similar tendencies in H/D, C_L, and H_W ratios were observed. These data suggest a definite relationship between tree shape and resistance to windthrow, whereby trees with small slenderness ratios and large crowns are more resistant to windthrow. It is also suggested that vulnerability of coniferous plantations to windthrow changes drastically at thresholds in H/D and C_L ratios. Therefore, coniferous plantations should be managed to reduce windthrow risk. Because tree shape is heavily influenced by stand density, risk management on plantations should include density control initiatives.
• 黒ボク土に立地するカラマツ林の養分制限 in‐growth bag法による養分制限の決定

  中原治, 石倉究, 花田健太郎, 竹内史子, 高橋正通, 永田修, 杉戸智子, 信濃卓郎, 渋谷正人, 波多野隆介  日本土壌肥料学会講演要旨集  56-  6  2010/09/07  [Not refereed][Not invited]
  
• 落葉広葉樹林での山火事後の高木類実生の更新に樹冠とササが及ぼす影響

  佐藤香織, 小林真, 斎藤秀之, 澁谷正人, 小池孝良  日本森林学会大会学術講演集(CD−ROM)  121st-  ROMBUNNO.PA2-16  2010/04/02  [Not refereed][Not invited]
  
• アカエゾマツ林とカラマツ林における中型土壌動物群集の比較

  末次直樹, 小池孝良, 澁谷正人, 斎藤秀之  日本森林学会北海道支部論文集  (58)  35-36  2010/02/19  [Not refereed][Not invited]
  
• 34 黒ボク土の森林の養分制限 : N制限か?P制限か?(北海道支部講演会,2008年度各支部会)

  花田 健太郎, 竹内 史子, 北村 さやか, 中原 治, 永田 修, 杉戸 智子, 高橋 正通, 澁谷 正人, 波多野 隆介  日本土壌肥料学会講演要旨集  55-  254  -254  2009/09/15
• シラカンバ林における火入れが土壌養分と生残木の葉内養分の動態に与える影響

  長谷川由布子, 小林真, 柴田英昭, 高橋廣行, 佐藤冬樹, 斎藤秀之, 渋谷正人, 小池孝良  日本森林学会大会学術講演集(CD−ROM)  120th-  ROMBUNNO.PA3-05  2009/03/25  [Not refereed][Not invited]
  
• 熱帯泥炭湿地に自生するトゥミ実生の湛水応答〜根の通気組織の発達〜

  丸上裕史, 斎藤秀之, 井上京, 渋谷正人, 小池孝良, SUWIDO Limin  日本森林学会大会学術講演集(CD−ROM)  120th-  ROMBUNNO.PB3-19  2009/03/25  [Not refereed][Not invited]
  
• Long term changes in size structure and in aboveground biomass of Larix cajanderi forests in eastern Siberia

  SHIROTA Tetsuoh, SAITO Hideyuki, SHIBUYA Masato, TAKAHASHI Kunihide, Maximov Trofim C.  Transactions of the Meeting in Hokkaido Branch of the Japanese Forest Society  (57)  65  -67  2009/02/21
• 東シベリアにおけるカラマツ林のサイズ構造と地上部現存量の推移

  城田徹央, 斎藤秀之, 渋谷正人, 高橋邦秀, MAXIMOV Trofim C  日本森林学会北海道支部論文集  (57)  65-67  2009/02/21  [Not refereed][Not invited]
  
• 火山灰土壌に立地するカラマツ林の養分制限

  花田健太郎, 竹内史子, 北村さやか, 中原治, 永田修, 杉戸智子, 高橋正通, 澁谷正人, 波多野隆介  日本土壌肥料学会講演要旨集  54-  10  2008/09/09  [Not refereed][Not invited]
  
• 異なる強度の土壌乾燥ストレスを受けたブナ苗木の灌水後の光合成と遺伝子発現

  石堂光, 斎藤秀之, 渋谷正人, 小池孝良  日本森林学会大会学術講演集(CD−ROM)  119th-  I16  2008/03/26  [Not refereed][Not invited]
  
• 熱帯泥炭湿地樹木4種の当年生時における土壌の湛水と乾燥ストレスに対する耐性評価〜器官量配分と根の形態ならびに光合成速度の反応から〜

  丸上裕史, 斎藤秀之, SAMPANG Gaman, LIMIN Suwido, 渋谷正人, 小池孝良  日本森林学会大会学術講演集(CD−ROM)  119th-  P3G06  2008/03/26  [Not refereed][Not invited]
  
• ニセアカシア種子の種皮の不透水性とその変化

  唐木貴行, 近藤哲也, 渡邉陽子, 門松昌彦, 秋林幸男, 笹賀一郎, 斉藤秀之, 渋谷正人, 小池孝良  日本生態学会大会講演要旨集  55th-  420  2008/03/14  [Not refereed][Not invited]
  
• The suitable condition for germination of Picea jezoensis in natural forests

  飯島 勇人, 渋谷 正人  Forest tree breeding of Hokkaido.  51-  (1)  20  -23  2008
• Development of water impermeability and germination characteristics in seeds of black locust (Robinia pseudoacacia)

  KARAKI Takayuki, KONDO Tetsuya, WATANABE Yoko, KADOMATSU Masahiko, AKIBAYASHI Yukio, SASA Kaichiro, SAITO Hideyuki, SHIBUYA Masato, KOIKE Takayoshi  Transactions of the Meeting in Hokkaido Branch of the Japanese Forest Society  56-  (0)  21  -23  2008  [Not refereed][Not invited]
  
• Stand Density Control Diagrams for Scots pine and Austrian black pine plantations in Bulgaria

  Tatiana Vassileva Stankova, Masato Shibuya  NEW FORESTS  34-  (2)  123  -141  2007/09  [Not refereed][Not invited]
   

  Stand Density Control Diagram (SDCD) is a stand-level mathematical model, which describes the relationships between yield, density and mortality throughout all stages of stand development. The SDCD is primarily used to derive density control schedules by management objectives. The main objectives of the present study are to define a modified model of SDCD for application to Scots pine (Pinus sylvestris L.) and Austrian black pine (Pinus nigra Arn.) plantations in Bulgaria, to examine the fitness of the model with representative experimental data sets from plantations of both species and to present a way of direct application of the SDCDs for practical purposes. The constructed SDCDs characterize the spatial-temporal dynamics of the pine plantations in a broad range of densities, forest sites and growth stages from 4 to 26 (28) m of dominant height class. The full density lines were fixed with self-thinning exponents alpha = 1.69 and alpha = 1.75 for Scots pine and Austrian black pine, respectively, and the trajectories of natural thinning for 23 initial densities (444-40000/ha) were determined. A direct way for application of the SDCDs to the plantation management was designed to estimate the optimal initial densities for the maximum attainable final yield and large-size wood production by self-thinning stands.
• Effects of surface and light conditions of fallen logs on the emergence and survival of coniferous seedlings and saplings

  Hayato Iijima, Masato Shibuya, Hideyuki Saito  JOURNAL OF FOREST RESEARCH  12-  (4)  262  -269  2007/08  [Not refereed][Not invited]
   

  We surveyed the germination number (Ncs) of 2-year and a 1-year survival of Abies sachalinensis and Picea jezoensis seedlings and saplings on 29 fallen logs from 2004 to 2005 in a natural coniferous forest in Hokkaido, northern Japan, in relation to the surface and light conditions of fallen logs. Moss height ( H-moss), log hardness (Hardness), and the area of fallen log (Area) were measured as the surface conditions by each 1-m block from bottom to top of all fallen logs. The relative photosynthetic photon flux density (rPPFD) 10 cm above the tallest seedling in each block was measured as the light condition. In addition, the height of the tallest seedling or sapling in each block (H-max), the difference between a height of each seedling and sapling and the Hmax (Shading), and a height of seedlings and saplings in 2004 (H-ini) were considered. Ncs of A. sachalinensis was affected by Hardness and Area, whereas Ncs of P. jezoensis was affected by Hmoss, Hardness, Area, Hmax, and rPPFD. The survival of seedlings (height < 5 cm) and saplings (5 cm <= height < 50 cm) were affected by Hini, rPPFD, and shading for both species. However, the survival of P. jezoensis saplings was more sensitive to decrease in rPPFD and increase of shading than that of A. sachalinensis. Therefore, seedling emergence was influenced by surface conditions, whereas survival was affected by light conditions. Furthermore, P. jezoensis emergence and survival were more sensitive to surface and light conditions than that of A. sachalinensis.
• 樹勢により落葉時期が異なるブナの葉の光合成と遺伝子発現—光合成と老化誘導に関連する遺伝子に着目して—

  林登志郎, 山田宰靖, 斎藤秀之, 澁谷正人  日本森林学会大会学術講演集(CD−ROM)  118th-  D14  2007/04/01  [Not refereed][Not invited]
  
• ブナ樹冠の葉におけるストレス状態を指標する遺伝子の発現特性〜季節変化とストレス応答〜

  山田宰靖, 林登志郎, 斎藤秀之, 澁谷正人  日本森林学会大会学術講演集(CD−ROM)  118th-  D13  2007/04/01  [Not refereed][Not invited]
  
• 倒木上のエゾマツおよびトドマツ実生の生残・成長に環境条件が与える影響

  飯島勇人, 渋谷正人, 斎藤秀之  日本森林学会大会学術講演集(CD−ROM)  118th-  K09  -288  2007/04/01  [Not refereed][Not invited]
  
• ポプラ葉の細胞分裂に関連する遺伝子群の発現と植物ホルモンの関わり合い

  高橋信行, 斎藤秀之, 榊原均, 小嶋美紀子, 澁谷正人  日本森林学会大会学術講演集(CD−ROM)  118th-  D15  2007/04/01  [Not refereed][Not invited]
  
• Spatial variation in tree seedling density after the site preparation for planting in a cleared coniferous plantation in Hokkaido, northern Japan

  ChangSeob Shin, Masato Shibuya  JOURNAL OF FOREST RESEARCH  12-  (1)  57  -62  2007/02  [Not refereed][Not invited]
   

  To study spatial variation in natural tree seedling density and the relationship between variation in seedling density and seed dispersal mode at a cleared site, we surveyed natural tree seedlings after the site preparation for planting in a coniferous plantation cleared by a typhoon disturbance in 2004. The site was located near Sikotsuko Lake, Hokkaido, northern Japan. Twenty-five tree seedling species were found and the mean seedling density was 9.8 seedlings/m(2). Seedlings of non-animal-dispersed species (7.2 seedlings/m(2)) were approximately five times more abundant than those of animal-dispersed species (1.4 seedlings/m(2)), and 87% of all seedlings were current. The seedling density of non-animal-dispersed species (almost all wind-dispersed) decreased with distance from a natural forest; however, this trend did not hold for animal-dispersed species (almost all bird-dispersed). The spatial variation in seedling density was lower in animal-dispersed species than in non-animal-dispersed species. Seed dispersal patterns and the viability duration of buried seeds likely affected the variation in seedling density by seed dispersal mode.
• Different biomass-allocation patterns among four tree species in heavily disturbed sites on a volcanic mountain in Hokkaido, northern Japan

  Masato Shibuya, Takashi Yajima, Mihoko Yoshida, Eiji Sasaoka  ECOLOGICAL RESEARCH  22-  (1)  177  -182  2007/01  [Not refereed][Not invited]
   

  We have compared biomass-allocation patterns and frequency of sprouting among saplings of four tree species (Larix kaempferi, Betula platyphylla var. japonica, Populus maximowiczii, and Populus sieboldii) growing on a volcanic mountain in Hokkaido, northern Japan. Growing conditions were very harsh on the mountainside. Leaf mass and fine root mass relative to root mass were larger in L. kaempferi, and L. kaempferi root mass was less than for the other species. Sprouting ratios were high for the broadleaved species. Different allometries and sprouting ratios among species suggest that survival strategies for L. kaempferi were different from those for the broadleaved species. L. kaempferi has greater ability to increase leaf mass under harsh growing conditions; this probably results in large photosynthetic production by L. kaempferi on the volcano. In contrast, the two Populus species and Betula platyphylla seem to maintain populations through their ability to produce sprouts from large root systems.
• ポプラの開芽・開葉期における個葉の細胞分裂と細胞分裂に関連する遺伝子群の発現特性

  高橋信行, 斎藤秀之, 渋谷正人, 高橋邦秀  日本森林学会大会学術講演集(CD−ROM)  117th-  B23  2006/04/03  [Not refereed][Not invited]
  
• エゾマツ・トドマツ稚樹群の動態に環境条件が与える影響

  飯島勇人, 渋谷正人, 斎藤秀之, 高橋邦秀  日本森林学会大会学術講演集(CD−ROM)  117th-  PC48  2006/04/03  [Not refereed][Not invited]
  
• 東シベリアにおけるカラマツ成熟林の林分構造の林分間変動

  城田徹央, 斎藤秀之, アヤル マキシモフ, アレキサンダー コノノフ, アレキサンダー イサエフ, トロフィン マキシモフ, 渋谷正人, 高橋邦秀  日本生態学会大会講演要旨集  53rd-  173  2006/03/24  [Not refereed][Not invited]
  
• The water relation of seedlings of Picea jezoensis on fallen logs

  H Iijima, M Shibuya, H Saito, K Takahashi  CANADIAN JOURNAL OF FOREST RESEARCH-REVUE CANADIENNE DE RECHERCHE FORESTIERE  36-  (3)  664  -670  2006/03  [Not refereed][Not invited]
   

  We examined whether fallen logs without moss (FLB) are more drought-stressful sites for Picea jezoensis Carr. seedlings than are logs with moss (FLM) and whether drought affects the mortality of seedlings on logs. We measured the water potential of the log humus layer (Psi(H)) and needles of seedlings on the logs (Psi(N)) in a natural forest and a greenhouse under various drought conditions. We also determined the critical Psi(N) from the relationship between seedling mortality, Psi(N), and chlorophyll fluorescence, Fv/Fm. The Psi(H) on both moss-covered and bare logs in the forest was 0 MPa, regardless of the number of days without precipitation. In the forest, the mean predawn Psi(N) of FLB and FLM measured 11 days after a rainfall was -0.8 and -0.7 MPa, respectively, in the driest season. The Psi(N) for P. jezoensis seedlings of FLB reached the critical value earlier than those of FLM in the greenhouse, but this occurred after a long period (> 30 days) with no irrigation. We conclude that drought does not cause mortality of P. jezoensis seedlings on fallen logs in natural forests.
• 東シベリアのカラマツ「Larix gmelinii」と「L.cajanderi」について

  城田徹央, 城田徹央, 斎藤秀之, 飯村佳代, 渋谷正人, 高橋邦秀  北海道の林木育種  48-  (2)  9-12  2006/01/25  [Not refereed][Not invited]
  
• Mean-dominant height relationships for Scotch pine and Austrian black pine plantations in Bulgaria

  Stankova, T, Stankov, H, Shibuya, M  Ecological Engineering and Environmental Protection  2-  59  -66  2006  [Not refereed][Not invited]
  
• Regeneration Process of Broadleaved Trees in Planted Larix kaempferi Forests

  Hanada N., Shibuya H., Saito H., Takahashi K.  JOURNAL OF THE JAPANESE FORESTRY SOCIETY  88-  (1)  1  -7  2006  [Not refereed][Not invited]
   

  To examine the regeneration process of broadleaved trees in planted larch (Larix kaempferi) forests, we investigated stand structures, species compositions and age distributions of broadleaved trees related to thinning histories, and species compositions of buried viable seeds in six planted larch forests located in the southern part of the Ishikari lowlands in Hokkaido, northern Japan. Density of broadleaved trees was lower in planted larch forests with dense sasa (Sasa spp.), and it was assumed that sasa inhibited the regeneration of broadleaved trees in planted larch forests. It was also assumed that thinning positively influenced the regeneration of broadleaved trees in the plantations, because the density of the trees increased after thinning. The number of species of broadleaved trees stepwise with thinning, and especially, the number of gap-dependent species markedly increased after the first thinning in the planted larch forests. Species composition of buried viable seeds was not similar to species composition of broadleaved trees. It was guessed that the seeds contributed little to the regeneration of broadleaved trees in planted larch forests, and yet more detailed examination of buried viable seeds in will be needed. Consequently, it was concluded that sasa negatively influenced the regeneration of broadleaved trees, and that thinning increased both density and species diversity of the trees in planted larch forests. Furthermore, it was suggested that the timing of the regeneration and species composition of broadleaved trees in planted larch forests are closely related to regeneration habits of the trees.
• 倒木上に播種したエゾマツの初期動態(2) 発芽や生残および成長に適した倒木

  飯島隼人, 渋谷正人, 斉藤秀之, 高橋邦秀  北方林業  57-  (10)  230-232  2005/10/01  [Not refereed][Not invited]
  
• 倒木上に播種したエゾマツの更新初期動態(1)発芽および生残に適した播種時期

  飯島 勇人, 渋谷 正人, 斎藤 秀之  北方林業  57-  (9)  201  -203  2005/09
• 風害後50年間の落葉広葉樹林の林分回復過程

  大沼直樹, 渋谷正人, 矢島崇, 斉藤秀之, 高橋邦秀  日本森林学会大会講演要旨集(CD−ROM)  116th-  PA044  2005/03/20  [Not refereed][Not invited]
  
• 北海道の主要な広葉樹の花粉制限と自家不和合性—その1—開花フェノロジーと結果結実—

  稲垣郁, 渋谷正人, 高橋邦秀, 斎藤秀之  日本森林学会大会講演要旨集(CD−ROM)  116th-  PA087  2005/03/20  [Not refereed][Not invited]
  
• 倒木上におけるエゾマツとトドマツの個体群構造と周囲環境の関係

  飯島勇人, 渋谷正人, 斎藤秀之, 高橋邦秀  日本森林学会大会講演要旨集(CD−ROM)  116th-  PA103  2005/03/20  [Not refereed][Not invited]
  
• イタヤカエデの開花と結実

  関根加奈子, 渋谷正人, 夏目俊二, 高橋邦秀, 斎藤秀之  日本森林学会大会講演要旨集(CD−ROM)  116th-  PA089  2005/03/20  [Not refereed][Not invited]
  
• 東シベリアのカラマツ成熟林における樹冠の光合成速度を制限する環境要因の評価—日中低下における葉温・葉面飽差・土壌水分の影響—

  小森弘基, 斎藤秀之, 城田徹央, 渋谷正人, マキシモフ TC, 高橋邦秀  日本森林学会大会講演要旨集(CD−ROM)  116th-  PA131  2005/03/20  [Not refereed][Not invited]
  
• ブナの葉のサイズ決定機構に関する研究—細胞分裂か?細胞肥大か?産地の異なるブナの葉の解剖学的解析から—

  斎藤秀之, 今のりえ, 船田良, 渋谷正人, 高橋邦秀  日本森林学会大会講演要旨集(CD−ROM)  116th-  3A28  2005/03/20  [Not refereed][Not invited]
  
• 東シベリアのカラマツ成熟林における樹冠の光合成速度を制限する環境要因の評価—降水の影響について—

  高池太二, 斎藤秀之, 小森弘基, 城田徹央, 渋谷正人, 高橋邦秀  日本森林学会大会講演要旨集(CD−ROM)  116th-  PA132  2005/03/20  [Not refereed][Not invited]
  
• 北海道の主要な広葉樹の花粉制限と自家不和合性—その2—花粉制限と自家不和合性—

  渋谷正人, 稲垣郁, 高橋邦秀, 斎藤秀之  日本森林学会大会講演要旨集(CD−ROM)  116th-  PA088  2005/03/20  [Not refereed][Not invited]
  
• 立地条件がサイシウモミの更新に与える影響

  ちょう慧卿, 高橋邦秀, 渋谷正人, 斎藤秀之, 金鍾真, 洪性かく, 金東遠  日本森林学会大会講演要旨集(CD−ROM)  116th-  PA032  2005/03/20  [Not refereed][Not invited]
  
• Effect of thinning on allometry and needle-age distribution of trees in natural Abies stands of northern Japan

  M Shibuya, H Hasaba, T Yajima, K Takahashi  JOURNAL OF FOREST RESEARCH  10-  (1)  15  -20  2005/02  [Not refereed][Not invited]
   

  We tested the effects of thinning on allometry and needle-age distribution in natural stands of Abies sachalinensis Masters by comparing a thinned stand to an unthinned, control stand. Specifically, we attempted to clarify how allometry was altered after a thinning. We assumed that the needle-age distribution of trees in the thinned stand would show a younger composition than in the control stand, given the effect of improved light conditions on needle dynamics following a thinning. These investigations were conducted in dense Abies stands located in central Hokkaido, northern Japan, 19 years post-thinning. In the thinned stand, the ratio of individual needle mass to stem mass increased significantly, as compared to the control. A difference in the H-DBH relationship between the stands was probably related to this tendency. Mean needle age of trees differed significantly between the two stands, and the thinned stand showed a younger needle age than the control. Within each stand, dominant trees showed older mean needle age than codominant or suppressed trees. These tendencies may have been caused by differential needle dynamics affected by light conditions in the stands, and by different crown positions among the trees within a stand. In summary, trees in the thinned stand showed increased growth rates after thinning, which were caused by increased needle mass, younger composition of needles, and improved light conditions.
• 低温湿層処理、温度、乾燥がサイシウモミとトドマツの発芽特性に与える影響

  趙 慧卿, 高橋邦秀, 渋谷正人, 斎藤秀之, 金 鍾眞, 洪 性珏  日本森林学会誌  87-  (6)  465  -470  2005  [Not refereed][Not invited]
   

  韓国の固有樹種で絶滅が危惧されているサイシウモミ(Abieskoreana)の天然更新にとって重要な種子の発芽特性を調べるため,発芽に対する低温湿層,温度,乾燥の影響について検討し,天然更新が比較的容易とされるトドマツ(Abies sachalinensis)と比較した。2樹種の種子は30~150日低温湿層処理によって発芽速度,発芽率が上昇した。150日間の低温湿層処理では,10~30°Cの各温度条件における最終発芽率は,無処理種子に比べ,サイシウモミで1.7~8.5倍(42.9~87.8%),トドマツで2.1~9.2倍(72.1~89.8%)まで増加した。しかし,サイシウモミの発芽速度はトドマツに比べ遅く,最終発芽率に達するのに各発芽温度で40日前後を要した。低温湿層処理後の発芽率の増加率は処理日数と温度によって異なっていた。低温湿層処理は,低温での発芽率を著しく増大させたが,サイシウモミではトドマツより長期間の低温湿層処理が必要であった。低温湿層処理後6日間までの無給水処理は発芽率に影響しなかった。しかし,PEG(Polyethylene glycol)6000溶液による乾燥処理によってサイシウモミの発芽率は有意に低下し,-0.4MPaでも無処理種子の50%まで低下した。一方,トドマツでは-0.8MPaでも無処理種子の80%を維持した。サイシウモミ種子はトドマツ種子に比べ,乾燥ストレスに影響されやすいが,発芽期間がトドマツより長く,晩霜害などによる被害を回避しやすいと推察された。
• Stand and self-thinning dynamics in natural Abies stands in northern Hokkaido, Japan

  M Shibuya, N Haga, T Sasaki, S Kikuchi, M Haruki, M Noda, K Takahashi, K Matsuda  ECOLOGICAL RESEARCH  19-  (3)  301  -309  2004/05  [Not refereed][Not invited]
   

  Stand dynamics and self-thinning were analyzed in relation to the dynamics of above-ground biomass in natural Abies sachalinensis stands growing on sand dunes in northern Hokkaido, Japan. This was done in order to examine wave-type regeneration in the stands. Fifty-two plots were established in almost pure Abies stands that ranged from saplings to the mature and collapsing growth stages. Above-ground biomass and tree height reached asymptotic levels prior to the collapsing phase, unlike wave-regeneration Abies stands in central Japan and North America. Stand density was high in the young growth stages, but the self-thinning rate, that is, the density decrease per biomass growth in the study stands was greater than in wave-regeneration stands in central Japan, as indicated by a large self-thinning exponent (-1.26 by reduced major axis regression). The range of tree height distribution was very narrow, and the stands' vertical structure was typically single-layered. The slenderness ratio of trees was large, except in young stands. In mature and collapsing stands, advanced seedling density increased markedly. These stand and tree characteristics were considered to be correlated with the wave-type regeneration in the study stands, and it is assumed that prevailing winds affect tree mortality.
• 新考・森林学—これからの森づくり(3) 種多様性を増進するカラマツ人工林

  渋谷正人, 花田尚子, 斉藤秀之, 高橋邦秀  北方林業  56-  (5)  113-116  2004/05/01  [Not refereed][Not invited]
  
• 低温湿層処理期間の違いによるサイシウモミとトドマツ種子の発芽反応

  ちょう慧卿, 高橋邦秀, 渋谷正人, 斎藤秀之, 金鍾真, 洪性かく  日本林学会大会学術講演集  115th-  667  2004/03/20  [Not refereed][Not invited]
  
• 異なるコケの厚さの倒木における土壌水分およびエゾマツ実生の葉の水ポテンシャルの関係

  飯島勇人, 斎藤秀之, 渋谷正人, 高橋邦秀  日本林学会大会学術講演集  115th-  406  2004/03/20  [Not refereed][Not invited]
  
• 異なる温度と明暗処理下でのサイシウモミ種子の吸水経過と発芽率

  CHO H K, 高橋邦秀, 渋谷正人, 斎藤秀之, KIM J J, HONG S G  日本林学会北海道支部論文集  (52)  90-92  2004/02/01  [Not refereed][Not invited]
  
• The Effect of Moss Height on Survival and Growth of Picea jezoensis Seedlings on Fallen Logs

  飯島勇人, 渋谷正人, 斎藤秀之, 高橋邦秀  日本林学会誌  86-  (4)  358  -364  2004  [Not refereed][Not invited]
   

  抄録：倒木上のコケの高さがエゾマツ実生の生残と成長に与える影響を明らかにするため、 コケがない倒木 (FLB)、 コケが低い倒木 (FLS)、 コケが高い倒木 (FLT) を対象に播種実験を行い、 エゾマツ実生の発芽率と生残率、形態ならびに根の分布、 各器官重を調査した。発芽率はFLTで有意に小さく、 生残率は倒木間で差がみられなかった。コケの高さや実生の生残・枯死によらず、 実生の主根の大部分は腐植層や材部に分布していた。当年生実生の個体重はFLT上で最も小さかったが、 FLT上の実生は他の倒木の実生より幹が長く、 幹へ多くの器官量配分を行っており、 高いコケによる被陰に対し形態および器官量配分による順応を行っていたと考えられた。1年生実生の個体重はFLSよりFLB上の実生が小さかった。FLB上の1年生実生の根長が有意に短く、 T/Rが高かったことから、 FLBでは1年生時の根の伸長が制限され、 個体の成長が抑制されたと考えられた。エゾマツの発芽および定着にはFLSが適していると考えられた。Abstract:We surveyed the germination and survival rates, morphological characteristics, spatial pattern of root extension, and the mass distribution into each organ of current and 1-year-old Picea jezoensis seedlings growing on fallen logs with no moss (FLB), short moss (FLS), and tall moss (FLT) in a natural coniferous forest in central Hokkaido, northern Japan, in order to estimate the in FLUence of moss height on the establishment of P. jezoensis seedlings on fallen logs. The germination rate was significantly lower on FLT than on the others. The survival rate of seedlings did not differ among the logs. Almost all parts of the tap roots of living and dead seedlings were distributed in the humus and wood layers of the logs, irrespective of moss height. Seedlings on FLT had longer stems and greater stem masses than seedlings on the other logs, which indicated their morphologic and allometric acclimation to shading from the tall moss. The masses of individual current-year seedlings were lower on FLT than on the others. The masses of individual 1-year-old seedlings were lower on FLB than on FLS. The root extension of 1-year-old seedlings on FLB was inhibited and resulted in shorter roots and a higher T/R ratio. Consequently, the growth of 1-year-old seedlings on FLB was inhibited. Therefore, FLS is the most suitable for the establishment of P. jezoensis seedlings.
• Time Trend in Aboveground Biomass, Net Primary Production, and Carbon Storage of Natural Larix gmelinii Stands in Eastern Siberia

  SHIBUYA Masato, SAITO Hideyuki, SAWAMOTO Takuji, HATANO Ryusuke, YAJIMA Takashi, TAKAHASHI Kunihide, CHA Joo Young, ISAEV Alexander P., MAXIMOV Trofim C.  Eurasian Journal of Forest Research  7-  (2)  67  -74  2004  [Not refereed][Not invited]
   

  Article
• Adaptation of Hagihara's competition-density theory for practical application to natural birch stands

  T Stankova, M Shibuya  FOREST ECOLOGY AND MANAGEMENT  186-  (1-3)  7  -20  2003/12  [Not refereed][Not invited]
   

  This study developed adaptation for practical application of Hagihara's competition-density (C-D) theory and examined the derived model with data of natural birch (Betula platyphylla var. japonica and Betula ermanii) stands in northeastern Japan. Stand mean height was introduced into the theory as an indicator of stand growth stage instead of stand age, and the theory adaptation started from expressing the coefficients A, and B of the reciprocal equation of the C-D effect in self-thinning stands (i.e. 1/w = A(t)rho + B, where w and p represent mean plant mass and density, respectively) through the mean height class. Parameter B was approximated closely by a power function of stand mean height class over all growth stages examined. Parameter A, in the equation decreased rapidly with increasing mean height, approaching a constant value, and was approximated by a function of mean height class, which was the difference between two power functions involving several hidden growth parameters of C-D theory. Our results approximated well the relationship between mean tree weight and density of stands grouped into 2 m mean height classes for both birch species. The parameters in the regressions of A, and B were used to express and to evaluate the principal growth parameters of the stands, such as mortality rate, self-thinning exponent, biological time, and asymptotic stand density, and their changes with stand growth are discussed for the birch stands. Furthermore, self-thinning lines for both species were determined theoretically, not empirically, using some of the parameters in the regression of A, and estimates of the asymptotic stand density. The evaluated lines fitted the upper boundaries of the mean tree weight-density relationship of each species well. (C) 2003 Elsevier B.V. All rights reserved.
• Changes in net ecosystem production associated with forest fire in Taiga ecosystems, near Yakutsk, Russia

  T Sawamoto, R Hatano, M Shibuya, K Takahashi, AP Isaev, RV Desyatkin, TC Maximov  SOIL SCIENCE AND PLANT NUTRITION  49-  (4)  493  -501  2003/08  [Not refereed][Not invited]
   

  Boreal and Taiga forests in Russia play an important role in carbon storage in terrestrial ecosystems. In this region, forest fires often occur, which affect considerably carbon cycling in the Taiga ecosystems. We estimated the net ecosystem production (NEP) in five ecosystems with different histories of forest fire in Yakutsk, Russia. The NEP was calculated as the difference between the net primary production (NPP) and annual soil organic matter decomposition (OMD). Severe burning and forest regeneration strongly affected OMD, NPP, and NEP. The NEP values were +1.24 and +1.40 Mg C ha(-1) year(-1) in two intact larch forests. But, the NEP values decreased to -0.89 and +0.07 Mg C ha(-1) year(-1) at two sites burned 5 years before. However, NEP showed the highest value, +2.39 Mg C ha(-1) year(-1), in a young larch forest burned 25 years before. The changes in NPP were considered to be a predominant factor for the changes in NEP in this region. Further studies should be carried out to analyze and/or estimate the changes in NPP after forest fire in relation to NEP in this region.
• 樹木の伐採が森林の物質循環と温暖化ガス動態にあたえる影響

  渋谷正人, 斎藤秀之, 波多野隆介, 森下智陽, 永田修, 高橋邦秀  食生活科学・文化及び地球環境科学に関する研究助成研究紀要  16-  95  -102  2003/05  [Not refereed][Not invited]
  
• 倒木上に生育するエゾマツ実生の枯死過程におけるクロロフィル蛍光反応

  飯島勇人, 斎藤秀之, 渋谷正人, 田内裕之, 高橋邦秀  日本林学会大会学術講演集  114th-  74  2003/03/20  [Not refereed][Not invited]
  
• PCR‐RFLPによるエゾマツ葉緑体DNAの地理的変異

  沢栗浩明, 斎藤秀之, 渋谷正人, 高橋邦秀, 河原孝行  日本林学会大会学術講演集  114th-  740  2003/03/20  [Not refereed][Not invited]
  
• ミズナラとミズナラ×カシワ雑種の光合成速度の日変化

  小森弘基, 斎藤秀之, 渋谷正人, 高橋邦秀, 門松昌彦, 生方正俊, 星比呂志  日本林学会大会学術講演集  114th-  736  2003/03/20  [Not refereed][Not invited]
  
• エゾマツ・トドマツ高齢造林地におけるアテ,水食い,腐朽材の発生実態

  松井崇史, 田保史明, 斎藤秀之, 渋谷正人, 高橋邦秀  日本林学会大会学術講演集  114th-  664  2003/03/20  [Not refereed][Not invited]
  
• カラマツ人工林のリターフォール量及び窒素還元量

  鈴木雅博, 渋谷正人, 斎藤秀之, 高橋邦秀  日本林学会北海道支部論文集  (51)  70-72  2003/02/01  [Not refereed][Not invited]
  
• 腐朽倒木上におけるエゾマツ,トドマツ実生および稚樹の生育ハビタットの違い

  矢野慶介, 高橋邦秀, 渋谷正人, 斎藤秀之  日本生態学会大会講演要旨集  49th-  151  2002/03/25  [Not refereed][Not invited]
  
• アブラムシの吸汁がブナ葉の光合成特性とRuBisCO量の季節変化に与える影響

  山室晃司, 斎藤秀之, 渋谷正人, 高橋邦秀, 尾崎研一  日本生態学会大会講演要旨集  49th-  227  2002/03/25  [Not refereed][Not invited]
  
• 東シベリアのカラマツ林の地上部現存量および堆積有機物層中の炭素・窒素貯留量

  渋谷正人, 斎藤秀之, 波多野隆介, 高橋邦秀  日本林学会大会学術講演集  113th-  48  2002/03/20  [Not refereed][Not invited]
  
• A method for density control of forest plantations

  Stankova, T, Shibuya, M, Hagihara, A  Hayka Зa Гopata  2-  27  -38  2002  [Not refereed][Not invited]
  
• Maintenance and Rehabilitation of the Mixed Conifer-Broadleaf Forests in Hokkaido, Northern Japan

  Matsuda Kyo, Shibuya Masato, Koike Takayoshi  Eurasian Journal of Forest Research  5-  (2)  119  -130  2002  [Not refereed][Not invited]
   

  Article
• 東シベリアのカラマツ林の地上部現存量と炭素貯留量（2）地上部現存量中およびA0層の炭素・窒素貯留量

  渋谷正人, 津野雄一, 斎藤秀之, 矢島崇, 高橋邦秀, 澤本卓治, 波多野隆介, 車柱栄, Isaev AP, Maximov TC  北方林業  53-  (10)  232  -234  2001/10  [Not refereed][Not invited]
  
• 東シベリアのカラマツ林の地上部現存量と炭素貯留量（1）林況と地上部現存量

  渋谷正人, 津野雄一, 斎藤秀之, 矢島崇, 高橋邦秀, 澤本卓治, 波多野隆介, 車柱栄, Isaev AP, Maximov TC  北方林業  53-  (9)  193  -196  2001/09  [Not refereed][Not invited]
  
• ロシアハバロフスク森林生態系における物質循環

  永田修, 波多野隆介, 渋谷正人, 斎藤秀之, 高橋邦秀, KONDRASHOV L  日本土壌肥料学会講演要旨集  47-  302  2001/03/25  [Not refereed][Not invited]
  
• 東シベリアカラマツ林における地上部現存量と窒素・炭素量

  津野雄一, 高橋邦秀, 渋谷正人, 斎藤秀之  日本林学会大会学術講演集  112th-  583  2001/03/20  [Not refereed][Not invited]
  
• 石狩海岸林におけるカシワの遺伝的変異

  日比野梓織, 門松昌彦, 斎藤秀之, 渋谷正人, 玉井裕, 高橋邦秀  日本林学会大会学術講演集  112th-  622  2001/03/20  [Not refereed][Not invited]
  
• ミズナラとミズナラ×カシワ雑種の光合成特性

  馬場久美子, 斎藤秀之, 高橋邦秀, 渋谷正人, 生方正俊, 河野耕蔵  日本林学会大会学術講演集  112th-  666  2001/03/20  [Not refereed][Not invited]
  
• アブラムシの吸汁を受けたブナの葉の光合成特性とRuBisCO・クロロフィル量

  山室晃司, 斎藤秀之, 渋谷正人, 高橋邦秀, 尾崎研一  日本林学会大会学術講演集  112th-  473  2001/03/20  [Not refereed][Not invited]
  
• Shoot Formation and Growth of Saplings afKalopanax septemlobus under Contrasting Light Conditions

  MICHIHIRO Jun, SHIBUYA Masato, YAJIMA Takashi, TAKAHASHI Kunihide  Transactions of the Meeting in Hokkaido Branch of the Japanese Forestry Society  (49)  12  -14  2001/02/22
• CO2, N2O, CH4 fluxes from soil in Siberian-taiga larch forests with different histories of forest fire

  Sawamoto, T, Hatano, R, Shibuya, M, Takahashi, K, Isaev, A.P, Desyatkin, R.M  Tôhoku Geophysical Journal  36-  77  -89  2001  [Not refereed][Not invited]
  
• Comparision of Needle Mass Density in The Tree Crowns of Larix gmelinii and Larix kaempferi Trees

  SIBUYA Masato, SUGIURA Tetsuya, TAKAHASHI KUnihide, SAWAMOTO Takuji, HATANO Ryusuke, CHA Joo Young, FUKUYAMA Kenji, ISAEV AlexanderP, MAXIMOV TrofimCithozone Russian Academy of Science  Eurasian journal of forest research  2-  39  -44  2001  [Not refereed][Not invited]
   

  Article
• ハリギリのアロザイム分析に用いる酵素種について

  野口千絵子, 門松昌彦, 玉井裕, 渋谷正人, 斎藤秀之, 高橋邦秀  日本林学会大会学術講演集  111th-  248  2000/03/30  [Not refereed][Not invited]
  
• Soil Moisture and Xylem Water Potential of Tree Saplings on Mt.Komagatake,Hokkaido

  SASAOKA Eiji, YOSHIDA Mihoko, YAJIMA Takashi, SHIBUYA Masato, TAKAHASHI Kunihide  Research bulletins of the College Experiment Forests, Hokkaido University  57-  (2)  105  -112  2000  [Not refereed][Not invited]
  
• Regeneration Pattern of Tree Species and Light Regime on Scarified sites with Sparse Canopy Trees in Northern Japan

  KURAHASHI Yoshiyuki, SHIBUYA Masato, YAJIMA Takashi, MATSUDA Kyo  Research bulletins of the College Experiment Forests, Hokkaido University  56-  (1)  55  -69  1999/02/26
• Reforestation on snow avalanche site in northern Hokkaido

  MATSUDA Kyo, YAJIMA Takashi, SHIBUYA Masato  Journal of the Japanese Association of Snow and Ice  61-  (2)  139  -147  1999  [Not refereed][Not invited]
   

  Tree saplings were planted in 1977 on a slope covered by Sasa bamboo in the Teshio Experiment Forest of Hokkaido University to prevent snow avalanches occuring every year and to restore the natural landscape of the slope. Before the planting, Sasa densely covering the slope was pruned away and short wood stakes were rammed in the upper part of the slope, and saplings of Abies, Picea and two species of Larix were planted in the slope. Then the slope was protected from snow avalanches in the following years, probably by effects of sasa-clearing and wood stakes, and the growth of saplings resulted in the reestablishment of a forest stand. After 19 years of the planting, mean heights of Larix, Abies and Picea attained 12, 7 and 4 m, respectively. Avalanches on the slope never occurred from 1978 to the present. Natural broad-leaved trees such as Quercus and Tilia species, which were inhibited their growth by the avalanche, also regained vigorous growth and attained their maximum height over 7 m. Present small patches on the slope are mixed stands of conifers and braodleaved trees. An overall discussion is given on the introduction method of trees to the slope with deep snow, especially from aspects of landscape restoration and expected costs.
• 北海道駒ケ岳における天然生カラマツ林の林分構造と成立過程

  日本林学会誌  81-  (1)  22  -28  1999  [Not refereed][Not invited]
  
• Reforestation on snow avalanche site in northern Hokkaido

  Kyo MATSUDA, Takashi YAJIMA, Masato SHIBUYA  Seppyo  61-  (2)  139  -147  1999  [Not refereed][Not invited]
  
• Stand structure and regeneration process of a natural Larix kaempferi stand on Mt. Komagatake, Hokkido

  E. Sasaoka, T. Yajima, M. Shibuya, K. Takahashi, F. Nakamura, O. Shimizu  Journal of the Japanese Forestry Society  81-  (1)  22  -28  1999  [Not refereed][Not invited]
   

  We studied distribution, stand structure and transition of stand structure by altitude of a naturally regenerated Larix kaempferi stand on Mt. Komagatake, a volcano on the island of Hokkaido. L. kaempferi dominated at altitudes from 200 to 1,000 m above sea level, although broadleaved trees dominated at the foot of the mountain. The stands on the mountain were composed of L. kaempferi, Betula spp., and Populus maximowiczii, and asortment of others. At 500 m a. s l., the stand dominant height was 2.0 to 6.1 m and basal area at ground level was 0.1 to 7.8 m2/ ha. These values indicate that the stand had intensively restricted growth. The stands at higher altitudes were less developed than at lower altitudes in dominant height and basal area at ground level. The present L. kaempferi gradually started being established in the area between 500 to 700 m a. s. l. during 20 to 50 years after the eruption in 1929. Thereafter the number of the established L. kaempferi increased remarkably. We believed that seed dispersal from artificial forests of L. kaempferi that have been planted since 20 years after the eruption, and from the individuals that had invaded the stands in the very early period, contributed to the increase of naturally regenerated L. kaempferi trees.
• The occurrence and diversity of ectomycorrhizas of Larix kaempferi seedlings on a volcanic mountain in Japan

  GT Yang, JY Cha, M Shibuya, T Yajima, K Takahashi  MYCOLOGICAL RESEARCH  102-  (12)  1503  -1508  1998/12  [Not refereed][Not invited]
   

  Larix kaempferi seedlings, in the process of becoming established during the revegetation process following a volcanic eruption, were assessed far the types, occurrence patterns and diversity of their ectomycorrhizas along an elevation gradient. On the basis of macro- and microscopic characteristics, 12 types of ectomycorrhizas were classified. In general, ectomycorrhizal types differed more by site than by seedling age. The majority of root systems of seedlings with an age ranging from 1 to 5 years were colonized by I or 2 types of mycorrhizal fungi at low and intermediate elevations, 2 or 3 types at a higher elevation. Under the more stressed environments of high and intermediate elevations, the mean D.W, of I yr old seedlings, 40% of which were colonized by 3 or 4 mycorrhizal fungi, was double the weight of the same aged seedlings at lower elevation sites, only 10% of which were colonized by 3 or 4 mycorrhizal fungi. The correspondence between the type and frequency of mycorrhizas, the elevation gradient and litter accumulation suggests that change in litter accumulation along gradient may influence not only mycorrhizal types and their occurrence, but also the diversity of mycorrhizas on one seedling. Diversity of mycorrhizas on the same seedling is assumed to be critical for the establishment of seedlings from the very beginning on stressed sites, and may also be influenced by the availability of nutrients. The more intensive competition between mycorrhizas that occurs due to a reduction in the food source (tip roots) shared by the mycorrhizal fungi with similar resource requirements, results in frequent co-occurrence of mycorrhizas in the same root system or even the same root tip. As a result, the diversity of mycorrhizal types seems to become simplified as the seedlings age.
• Tree damage by sika deer in a wintering area in the Iwaobetu disstrict on the Siretoko peninsula

  Sakabe Tomoko, Yabe Tuneaki, Yajima Takashi, Shibuya Masato, Takahashi Kunihide  Research bulletins of the College Experiment Forests, Hokkaido University  55-  (1)  113  -122  1998/02
• Cultural characteristics of Biological Species of Armillaria from Hokkaido, Japan

  Cha Joo Young, Shibuya Masato, Yajima Takashi, Takahashi Kunihide, Igarashi Tsuneo  Research bulletins of the College Experiment Forests, Hokkaido University  54-  (2)  212  -222  1997/09
• Changes in biomass of above- and under-ground parts in Sasa kurilensis and Sasa senanensis stands with culm height

  矢島 崇, 渡辺 訓男, 渋谷 正人  日本林学会誌  79-  (4)  234  -238  1997  [Not refereed][Not invited]
   

  抄録：ササ群落の稈高が連続的に変化する場所において、稈基繁殖型であるチシマザサと地下茎繁殖型であるクマイザサを対象とし、稈枝•葉•地下茎•稈基などの器官量の稈高にともなう変化について明らかにした。また器官量間の関係を両種で比較して、稈高が制限されるような場所での両種の形態の可塑性を検討した。調査区の平均稈高はチシマザサでは59～261cmでクマイザサでは30～107cmであり、斜面上部ほど低かった。両種とも、稈高が制限されると稈枝と葉が小型化することによって地上部現存量が減少したが、稈密度や分枝特性、稈寿命、単位面積当りの葉枚数はあまり変化しなかった。クマイザサは稈高が低下してもC/F比とT/R比に大きな変化がなく、各器官がほぼ同じ比率で小型化していた。チシマザサは稈高の低下にともなって特に稈枝量の減少が大きく、C/F比が小さくなった。地下部では稈高の低下にともなって稈基量が減少したが地下茎は長くなり節数が増えて地下茎量は相対的に増加しT/R比が低下していた。稈高が制限されるような場所での両種の形態変化には明らかな差異が認められた。Abstract:The biomass of above- and under-ground parts were studied in stands of bamboo grass, Sasa kurilensis and Sasa senanensis, with different stand heights to compare their plastic variation of mass allocation between organs depending on the culm height. The mean stand heights were 59261 cm in S. kurilensis plots, and 30107 cm in S. senanensis plots. Mean stand height reduced distinctly toward the upper part of hillside. The stand height of bamboo grass might be affected by stress such as high wind or thin snow. The above-ground biomass decreased, and culms, branches and leaves became smaller where mean culm height was limited. Whereas culm density, branching pattern, mean life span of culm and the number of leaves per m2 did not change as much in both species. S. senanensis showed small changes in the C/F ratio and T/R ratio with culm height, and its mass allocation between organs was rather stable irrespective of culm height. S. kurilensis showed obvious changes in organ allocation with a reduction of culm height. In S. kurilensis, the mass of culm and branch decreased significantly and rhizome mass increased relatively in under-ground parts because the culm base mass had reduced with decreased culm height.
• 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  日本林学会誌  79-  (4)  195  -201  1997  [Not refereed][Not invited]
   

  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.
• シラカンバ林の密度管理図-成長にともなう平均材積-密度関係の推移にもとづく密度管理図の修正-

  北海道大学農学部演習林研究報告  54-  (2)  202  -211  1997  [Not refereed][Not invited]
  
• Changes in biomass of abeve-and under-ground parts in Sasa kurilensis and Sasa senanensis with culm height

  矢島 崇, 渡辺 訓男, 渋谷 正人  Journal of the Japanese Forestry Society  79-  (4)  234  -238  1997  [Not refereed][Not invited]
   

  抄録：ササ群落の稈高が連続的に変化する場所において、稈基繁殖型であるチシマザサと地下茎繁殖型であるクマイザサを対象とし、稈枝•葉•地下茎•稈基などの器官量の稈高にともなう変化について明らかにした。また器官量間の関係を両種で比較して、稈高が制限されるような場所での両種の形態の可塑性を検討した。調査区の平均稈高はチシマザサでは59～261cmでクマイザサでは30～107cmであり、斜面上部ほど低かった。両種とも、稈高が制限されると稈枝と葉が小型化することによって地上部現存量が減少したが、稈密度や分枝特性、稈寿命、単位面積当りの葉枚数はあまり変化しなかった。クマイザサは稈高が低下してもC/F比とT/R比に大きな変化がなく、各器官がほぼ同じ比率で小型化していた。チシマザサは稈高の低下にともなって特に稈枝量の減少が大きく、C/F比が小さくなった。地下部では稈高の低下にともなって稈基量が減少したが地下茎は長くなり節数が増えて地下茎量は相対的に増加しT/R比が低下していた。稈高が制限されるような場所での両種の形態変化には明らかな差異が認められた。Abstract:The biomass of above- and under-ground parts were studied in stands of bamboo grass, Sasa kurilensis and Sasa senanensis, with different stand heights to compare their plastic variation of mass allocation between organs depending on the culm height. The mean stand heights were 59261 cm in S. kurilensis plots, and 30107 cm in S. senanensis plots. Mean stand height reduced distinctly toward the upper part of hillside. The stand height of bamboo grass might be affected by stress such as high wind or thin snow. The above-ground biomass decreased, and culms, branches and leaves became smaller where mean culm height was limited. Whereas culm density, branching pattern, mean life span of culm and the number of leaves per m2 did not change as much in both species. S. senanensis showed small changes in the C/F ratio and T/R ratio with culm height, and its mass allocation between organs was rather stable irrespective of culm height. S. kurilensis showed obvious changes in organ allocation with a reduction of culm height. In S. kurilensis, the mass of culm and branch decreased significantly and rhizome mass increased relatively in under-ground parts because the culm base mass had reduced with decreased culm height.
• Recovering process and dynamics of the number of stems of major 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  Journal of the Japanese Forestry Society  79-  (4)  195  -201  1997  [Not refereed][Not invited]
   

  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.
• A modified stand density control diagram for Japanese white birch based on a trend of mean volume-density relationships with stand growth

  SHIBUYA M.  Research Bulletin of the Hokkaido University Forests  54-  (2)  202  -211  1997  [Not refereed][Not invited]
  
• Distributional interrelationship between tree species in natural mixed-species forests : Birches rarely appear under oak crowns in scarified sites

  SHIBUYA Masato, KOJIMA Yasuo, MATSUDA Kyo  Transactions of the Meeting in Hokkaido Branch of the Japanese Forestry Society  (44)  70  -72  1996/02/28
• Formational change of lateral branch leaders and skewed foliage mass distribution in lateral branches observed in Thujopusis dolabrata var. hondae saplings

  内海 洋太, 渋谷 正人, 矢島 崇  日本林学会誌  78-  (4)  457  -460  1996  [Not refereed][Not invited]
   

  抄録：ヒノキアスナロの稚樹や伏条枝で頻度高く観察される側枝の先端部における枝条展開パタンの変化(芯形成)について、芯を形成する側枝のサイズ、芯形成の頻度、および側枝内における同化器官、非同化器官量の分布の特徴について検討し、芯形成の意味について考察した。調査した全側枝のうち29%で芯形成が生じていた。芯形成は、枝長が長くC/F比が高い低位置の側枝で多くみられた。また上位の側枝の葉量の多い箇所よりさらに樹冠の外側で芯形成が生じ、芯を形成した側枝では、葉量は芯から枝先端部分に集中し偏った分布をする傾向が認められた。これらのことから、芯形成は葉量を確保するという働きがあり、低照度下において個体あるいは側枝の生残に大きな役割を果たしているのではないかと推察された。さらに観察した伏条枝のうち95%で芯形成がみられたが、これは芯形成が着生位置の低い長い枝で生じることが多いためであると考えられた。Abstract:Branch length distribution, frequency of formational change in lateral branches, and foliage mass distribution in individual branches were examined for Thujopusis dolabrata var. hondae saplings to examine the ecological causes of the formational change in branches. Formational changes were observed in 29% of all lateral branches studied, and were more frequent in branches ramified at lower height. Lateral branches showing formational change were characterized by their longer length and high C/F ratio compared with branches with no formational changes. Foliage mass on branches having formational change showed a skewed distribution and were concentrated in peripheral shoots extending from the outer crown of the formational change. We hypothesize that the formational change provided the sufficient foliage mass for the survival of saplings and lateral branches in extremely low light. Most of the observed layerings (95%) showed formational change. However, this tendency is probably to be attributable to the fact that branches with formational changes tend to be longer and ramify at lower heights than those with no formational changes.
• Formational change of lateral branch leaders and skewed foliage mass distribution in lateral branches observed in ┣DBThujopusis(/)-┫DB ┣DBdolabrata(/)-┫DB var. ┣DBhondae(/)-┫DB saplings

  内海 洋太, 渋谷 正人, 矢島 崇  Journal of Japanese forestry Society  78-  (4)  457  -460  1996  [Not refereed][Not invited]
   

  抄録：ヒノキアスナロの稚樹や伏条枝で頻度高く観察される側枝の先端部における枝条展開パタンの変化(芯形成)について、芯を形成する側枝のサイズ、芯形成の頻度、および側枝内における同化器官、非同化器官量の分布の特徴について検討し、芯形成の意味について考察した。調査した全側枝のうち29%で芯形成が生じていた。芯形成は、枝長が長くC/F比が高い低位置の側枝で多くみられた。また上位の側枝の葉量の多い箇所よりさらに樹冠の外側で芯形成が生じ、芯を形成した側枝では、葉量は芯から枝先端部分に集中し偏った分布をする傾向が認められた。これらのことから、芯形成は葉量を確保するという働きがあり、低照度下において個体あるいは側枝の生残に大きな役割を果たしているのではないかと推察された。さらに観察した伏条枝のうち95%で芯形成がみられたが、これは芯形成が着生位置の低い長い枝で生じることが多いためであると考えられた。Abstract:Branch length distribution, frequency of formational change in lateral branches, and foliage mass distribution in individual branches were examined for Thujopusis dolabrata var. hondae saplings to examine the ecological causes of the formational change in branches. Formational changes were observed in 29% of all lateral branches studied, and were more frequent in branches ramified at lower height. Lateral branches showing formational change were characterized by their longer length and high C/F ratio compared with branches with no formational changes. Foliage mass on branches having formational change showed a skewed distribution and were concentrated in peripheral shoots extending from the outer crown of the formational change. We hypothesize that the formational change provided the sufficient foliage mass for the survival of saplings and lateral branches in extremely low light. Most of the observed layerings (95%) showed formational change. However, this tendency is probably to be attributable to the fact that branches with formational changes tend to be longer and ramify at lower heights than those with no formational changes.
• Stand structures and species compositions of mixed stands of Sasa kurilensis and Sasa senanensis

  WATANABE Norio, YAJIMA Takashi, SHIBUYA Masato  Transactions of the Meeting in Hokkaido Branch of the Japanese Forestry Society  (43)  198  -199  1995/02/28
• 林分の平均サイズ-密度トラジェクトリーの単純で実用的なモデル

  日本林学会誌  77-  (3)  247  -253  1995  [Not refereed][Not invited]
  
• Occurrence and types of ectomycorrhizae present in seedlings of Picea glehnii in a natural forest in Hokkaido

  Maria Catarina Megumi Kasuya, Tsuneo Igarashi, Masato Shibuya  Mycoscience  36-  (3)  335  -339  1995  [Not refereed][Not invited]
   

  Picea glehnii seedlings whose ages ranged from 2 to 5 years and which were growing in a P. glehnii-Abies sachalinensis natural forest where the surface had been scarified 6 years before, were assessed for the occurrence and types of ectomycorrhizae. Based on the macro- and microscopic characteristics, 34 types of ectomycorrhizae were classified. The basidiomycetes were clearly dominant and it was common to observe more than one type of mycorrhiza occurring in the same root tip. The diversity of mycorrhizal types and the presence of at least one type of ectomycorrhiza in a single seedling, observed in this work, indicate a very dynamic system of mycorrhizal formation in P. glehnii seedlings, which allows them to survive and grow in a forest surface subjected to soil scarification. © 1995, Mycological Society of Japan. All rights reserved.
• A simple and practical model for mean size-density trajectories of tree stands

  SHIBUYA M.  Journal of the Japanese Forestry Society.  77-  (3)  247  -253  1995  [Not refereed][Not invited]
  
• Maximum yield and the C-D effects in natural white birch stands

  M Shibuya  ECOLOGICAL RESEARCH  9-  (3)  325  -332  1994/12  [Not refereed][Not invited]
   

  The competition-density effect for natural Japanese white birch (Betula platyphylla var. japonica) stands, located in the northern part of Hokkaido Island, was examined for various growth stages to establish mean tree weight-density relationships over a considerable extent of stand growth of white birch. Aboveground yields of investigated stands ranged from 16.0 to 161.7 t.ha(-1), and it was recognized that maximum aboveground yield of this species was about 160 t.ha(-1). Constants A and B of the reciprocal equation of the C-D effect, 1/w = AN + B (w, mean tree weight; N, tree density), were related to mean height classes of birch stands. Constant B was related to the entire mean height classes as the allometric relationship. On the other hand, constant A had an allometric relationship to mean height classes under 16 m, but became fixed over the 16 m class. White birch stands can come up to the maximum yield approximately at the stage of the 16 in class. The asymptotic tendency seemed to be appropriate for constant A-mean height class relationship. The maximum yield of white birch stands was predicted by the asymptotic value of A. The trend of mean tree weight-density relationships with stand growth also changed with constant A. It was considered that maximum yield was an important characteristic for practical applications of the C-D effect to agriculture and forestry.
• シラカンバ天然林の最大収量とC-D効果

  SHIBUYA M  9-  (3)  325  -332  1994  [Not refereed][Not invited]
  
• Biomass Estimations of Aerial Organs of Natural White Birch Trees

  渋谷 正人, 松田 彊  Research bulletin of the Hokkaido University Forests  50-  (2)  p207  -218  1993
• Crown Component Biomass Estimations for Natural White Birch Trees and Stands

  SHIBUYA Masato  Journal of the Japanese Forestry Society  74-  (6)  509  -513  1992/11/01
• Surgical Treatment of Middle Cerebral Aneurysms( Surgical Treatment for Cerebral Aneurysms)

  Shibuya Masato  Japanese journal of neurosurgery  1-  (4)  313  -321  1992/10/20  

  Middle cerebral aneurysms can develop from a variety of locations but most aneurysms occur at M_1 bifurcation, although the origin of the anterior temporal artery, the lenticulostriate artery, and the area distal to the M_2 segments are also likely sites. There are two major surgical approaches to consider for an aneurysm at the M1 bifurcation : the proximal approach, which proceeds from the internal carotid, the M_1, and the bifurcation : and the distal approach, which proceeds from the M_2 directly to the M_1 bifurcation and the aneurysm. We use both approaches interchangeably, even in one patient, whichever was considered safer and less traumatic to the brain. Body clipping is a major surgical requirement for a wide-necked aneurysm, and a combination of the most suited multiple clips should be used on aneurysms with arterial branching. Temporary clips should be limited to cases of a premature aneurysmal rupture, or if an aneurysm appears imminent, or when puncturing the aneurysm to reduce its mass. In all instances, however, the brain must be protected before applying any temporary clip. Although early removal of the blood clot is the best way to prevent the occurrence of a vasospasm, it is impossible to surgically remove a clot sited deeply in the insular cistern. The intrathecal use of thrombolytic agents seems to be promising procedure, provided that their side effect (bleeding) can be controlled. However, no single drug treatment has been found successful. Thus, a combination of several drugs with different mechanisms of action may have to be used to abolish the vasospasm.
• Stand dynamics in a young birch (Betula ermanii) stand and its competition process inferred from the frequency distribution of above-ground organ weight

  SHIBUYA Masato, IGARASHI Tsuneo  Jounrnal of the Japanese Forestry Society  74-  (2)  102  -108  1992  [Not refereed][Not invited]
  
• ミズナラ二次林における間伐.枝打ちおよび地表処理の効果

  北海道農学部演習林報告  48-  (1)  1991  [Not refereed][Not invited]
  
• 樹下植栽されたトドマツ人工林の成長と現存量

  北海道大学農学部演習林報告  48-  (2)  1991  [Not refereed][Not invited]
  
• Tending effects of thinning, pruning and soil-exposure of the forest floor in natural secondary oak (Quercus mongolica var. grosseserrata) stands in Hokkaido

  The Research Bulletins of the College Experiment Forests  48-  (1)  1991  [Not refereed][Not invited]
  
• Growth and biomass of an artificial todo-fir (Abies sachalinensis) stand planted in the natural broad-leaved forest

  The Research Bulletins of the College Experiment Forests  48-  (2)  1991  [Not refereed][Not invited]
  
• ドマツ巣植え造林地における個体成長と根系について

  北海道大学農学部演習林報告  46-  (3)  1989  [Not refereed][Not invited]
  
• Individual growth and roots distiribution in a todo-fir (Abies sachalinensis)stand planted in clumps

  The Research Bulletius of the College Experiment Forests.  46-  (3)  1989  [Not refereed][Not invited]
  
• A yield-density diagram of natural birch stands

  SHIBUYA Masato, KIKUZAWA Kihachiro  Transactions of the Meeting in Hokkaido Branch of the Japanese Forestry Society  (36)  124  -126  1988/03/01
• トドマツ林分の齢構成と個体の生長経過について

  北海道大学農学部演習林報告  44-  (1)  1987  [Not refereed][Not invited]
  
• Age distribution and individual growth pattern in todo fir (Abies sachalinensis)stands

  The Research Bulletins of the College Experiment Forests  44-  (1)  1987  [Not refereed][Not invited]
  

Association Memberships

• 日本植物学会   森林計画学会   日本生態学会   日本林学会   

Works

• 北方森林圏の火災によって引き起こされる陸域-大気相互作用の検出と予測

  1999
• Detection and Prediction of Land-Atmosphere interaction Changes Induced by Boreal Forest Fire

  1999
• 温暖化ガスにかかわる永久凍土撹乱の制御技術

  1997
• Control technology of permafrost disturbance affecting the greenhouse-gas dynamics

  1997

Research Projects

• Effects of P limitation on nutrient cycling intemperate forests

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research

  Date (from‐to) : 2009 -2011 

  Author : NAKAHARA Osamu, SHIBUYA Masato

   

  We examined nutrient limitation in 26 stands of larch forest onvolcanic parent material deposited 300-20,000 y BP at Mt. Shirahata, Sapporo, Japan.Root-ingrowth bioassay showed that of the 26 stands examined 13were N limited,3were Plimited, and 10 were N and P colimited. Nitrogen limitation was common in stands with afoliar N:P ratio<16. In stands with foliar N:P ratio>16, colimitation by N and P dominated,but P limitation was observed at three stands.
• Effect of nitrogen deposition on fluxes of green house gases in a forest ecosystem

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research

  Date (from‐to) : 2003 -2005 

  Author : HATANO Ryusuke, NAKAHARA Osamu, HATA Hiroshi, SHIBUYA Masato

   

  Nitrogen deposition has been known to affect emission and absorption of green house gases in forest ecosystems. Nitrogen deposition enhances nitrous oxide emission from forest soils and inhibits methane emission into forest soils. Nitrogen deposition might enhance or diminish forest growth and CO_2 sequestration. Most researches, however, focus on nitrogen-saturated forests receiving high deposition of nitrogen (DIN > 10 kgN ha^<-1> y^<-1>), and we need more information on the effect of nitrogen deposition on green house gases fluxes in forests receiving low nitrogen deposition (DIN < 10 kgN ha^<-1> y^<-1>). IPCC proposed the concept of 'Global Warming Potential' (GWP) as a comprehensive measure of effect of ecosystem biogeochemical processes on global warming. Previous studies mainly focused on one of these green house gases, e.g., carbon dioxide, nitrous oxide and methane. Very few studies reported total effect of these gases or GWP of forest ecosystems. The purpose of this study is to reveal the effect of very low nitrogen deposition on GWP in a larch forest. We studied at five sites in larch forest in Mt. Shirahata, Sapporo city, northern Japan. N_2O emission and CH_4 absorption at the surface of soil/snowpack were measured with closed chamber method. CO_2 sequestration was estimated with measurement of tree heights and diameters at breath height, allometric equation, and microbial respiration measured by incubation of moist soils in laboratory. Nitrogen deposition during no-snow season ranged 0.8 〜 1.8 kgN ha^<-1> y^<-1>. Annual CH_4 absorption ranged 5 〜 7 kgC ha^<-1> y^<-1> and showed no correlation with nitrogen deposition. But comparison of our result with literature data suggested that high CH_4 absorption in this study site was caused by very low nitrogen deposition that is known to inhibit CH_4 absorption. Nitrous oxide emission in this study was classified as background type emission because N_2O emission showed no correlation with soil temperature and soil moisture. Background type N_2O emission has been believed not to affected by nitrogen deposition. Annual N_2O emission ranged 0.02 〜 0.09 kgN ha^<-1> y^<-1>. Accumulated N_2O emission during no-snow season showed positive correlation to nitrogen deposition during now-snow season. Comparison of our results with literature data on background type N_2O emission suggested that even background type N_2O emission is affected by nitrogen deposition. Net ecosystem productivity (NEP) ranged 0.2 〜 2.1 tC ha^<-1> y^<-1>. NEP showed positive correlation to nitrogen deposition during no-snow season. Calculation of GWP revealed that CO_2 sequestration by forest vegetation was largest component in GWP in this study site ; contribution of N_2O emission and CH_4 absorption to GWP was negligible. In summary, nitrogen deposition has a negative effect on global warming and tree growth enhancement by nitrogen deposition has much larger role than enhanced N_2O emission and reduced CH_4 absorption by nitrogen deposition.
• Effect of surface fires on the fixation of carbon dioxide by eastern Siberian taiga

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research

  Date (from‐to) : 2003 -2005 

  Author : TAKAHASHI Kunihide, HASEGAWA Shuuich, SHIBUY Masato, SAITO Hideyuki

   

  The object of this project is to estimate the effects of surface fires on the fixation of carbon dioxide by eastern Siberian taiga and vegetation recovery after a fire. Artificial surface fire was carried out at a mature larch forest near Yakutsk, the capital city of Sakha Republic. Vegetation recovery was observed in two larch forests which burned severely in 2002. The total amount of organic matters burned by the artificial surface fire was 48% of a control site and was estimated low or middle intensity of surface fire. Maximum soil surface temperature was 485℃. Soil temperature at 5cm depth reached 116℃ and kept more than 50℃ for 3 hours. Depression of photosynthesis rate of larch crown in the afternoon decreased significantly compared with the control site just after fire. This phenomenon is assumed that soil water which is used by burned forest floor vegetation by the surface fire could be used by larch trees. Vegetation recovery was influenced by the intensity of fire and soil moisture conditions. Vegetation cover developed faster in a wet site than in a dry site, but 2.2 seedlings/m^2 of larch grew in the dry site. Larch seedlings hardly grew but many birch seedlings grew in wet site. Carbon release of these young and dense larch forests was estimated 34〜37tC/ha. The estimation of the effects of this artificial surface fire needs several years because dieback of larch trees after surface fire was reported to occur for several years.
• Ecophysiological Study on Maintenance Mechanism of Boreal Coniferous Forests on Coastal Dunes and Evaluation on Conservant Function of Front Dune

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research

  Date (from‐to) : 1997 -2000 

  Author : TAKAHASHI Kunihide, KIKUCHI Shunichi, SHIBUYA Masato, YAJIMA Takashi, HARUKI Masahiro, NODA Makoto

   

  The purpose of this study is to investigate the maintenance mechanism of Abies sachlinensis natural forests on coastal dunes and to evaluate the conservant function of a front dune line at Wakasakanai coastal forests, northern part of Hokkaido. The spatial patterns of regeneration, the relationship between tree shapes and coastal wind, the soil properties of dunes, the physiological characteristics of Abies, the crown structures and their utilization of light, tree ring analysis, above-ground biomass and a collapse model were investigated. The stand density of Abies is 160,000/ha in 26-years-old to 600/ha in over 77-years-old. A regeneration area of Abies forests is 1,000〜4,0O0m^2 and the size on coast side is larger than that on inland side. Collapse of forests had begun from coast side. South to east wind (land wind) prevails in summer and north to west wind (sea wind) in winter. Average wind velocity is stronger in winter than in summer. Strong wind during winter caused a clustered to leeward. Cut of the front dune line has caused the collapse of forest and high chloric ion of soil. Tree ring analysis showed that the cut of front dune had affected on the growth and collapse of forests. Leaf mass less than 4-years-old of Abies is 70〜100% of all leaf mass. Limit of tree height is 12 m and collapse will start around 80 years. It is clear that a front dune line protects Abies forest.
• Exudation Mechanism of Tree Sap

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research

  Date (from‐to) : 1998 -1999 

  Author : TERAZAWA Minoru, SHIBUYA Masao, FUNADA Ryo, TAKAHASHI Kunihide, SANO Yuzou, TAMAI Yukata

   

  Sap exudation : The period of the starting point of the sap exudation of birch trees coinsides with that the earth temperatures become above 0℃. The amount of the sap exudated in the one season corelates with the atomospheric temperatures and the change in the amount of sap exudated within a day corelates with the changes in atomospheric temperatures. Production in the leaves in a summer influences the amount of sap exudation in the following spring. Water distribution : The sap in the tracheids disappears gradually towards winter and disappear completely in the period just before the sap exudation starts by the repetition of freezing of the xylem and its re-freezing. The recovery of the cavitation seems to be derived by the pressures in the roots. Actually, the swelling of the roots during the sap exudation process was observed. The process of the refilling of the sap in the tracheids of the xylem was photographically recorded by Cryo-SEM techniques. The osmotic pressures in the sap of xylem tracheids and the function of the water pumping proteins in roots and trunks are the next targets to be investigated.
• Effects of Forest Fire on Biosphere and Cryosphere -Biodiversity and Carbon Droxide Cycle of in Northern Eurasia-

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research

  Date (from‐to) : 1997 -1999 

  Author : TAKAHASHI Kunihide, YAJIMA Takashi, SHIBUYA Masato, HATANO Ryusuke, FUKUYAMA Kenji, FUKUDA Masami

   

  The results of the present project are summarized as follows: 1. Biomass: Larch forests in permafrost area near Yakutsk show pure and uniform forest types. Tree height and stand density of a 22-year-old, a 120-year-old, and a more than 200-year-old forests are about 5 m and 10,000 trees/ha, 10 m and 6,000 trees/ha, and 9〜13 m and 2,000 trees/ha respectively. The biomass above ground increased straight from 16.2 t/ha to 149.6 t/ha with increasing the age until around 120 years old. The maximum biomass estimated from 31 stands reported previously around Yakutsk was about 150 t/ha. The biomass and the leaf mass positively correlated with diameter at 1.3 m. 2. Biodiversity : 106 plant species which included 16 tree species and 90 herbaceous plants were recorded in our research sites during the investigation periods. Vaccinum, Arctous and lichens were dominant on the forest floor of old growths. Specific plant species corresponded to high pH or soil moisture appeared at alas meadow. Collembola and Cryptostigmata decreased their density to the lowest value at 6 years after forest fire and increased them with being recovered by larch forest. The density of both Collembola and Cryptostigmata positively correlated with the nitrogen content of soil and that of Cryptostigmata negatively correlated with the high soil pH. 3. Carbon cycle and methon flux: Net ecosystem production(NEP) of larch old growth was estimated at 129 gC/mィイD12ィエD1/yr from soil respiration and net primary production, however that of the forest fired strongly was -88 gC/mィイD12ィエD1/yr, namely a source of COィイD22ィエD2. Forest soil fired or not was absorbing NHィイD24ィエD2 but the edge of marsh in alas was emitting NHィイD24ィエD2.
• Forest recovery after intense disturbance by volcanic activity

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research

  Date (from‐to) : 1996 -1998 

  Author : YAJIMA Takashi, CHA Joo Young, SHIMIZU Osamu, NAKAMURA Futoshi, SHIBUYA Masato, TAKAHASHI Kunihide

   

  We studied distribution and stand structure of a naturally regenerated Larix kaempferi stand on Mt. Komagatake, a volcano on the island of Hokkaido. Further, biomass allocation, dynamics of shoots, and seasonal changes of water potential were examined in saplings of L.kaempferi and some broadleaved trees. The stands on the mountain were composed of L.kaempferi, Betula spp. and Populus maximowiczii, and assortments of others. At 500m a. s. 1., the stand dominant height was 2.0 to 6.1m and basal area at ground level was 0.1 to 7.8 m^2/ha. These values indicate that the stand intensively restricted growth. The stands at higher altitudes were less developed than at lower altitudes in dominant height and basal area. The present L.kaempferi gradually started being established in the area between 500 and 700m a. s. 1. during 20 to 50 years after the eruption in 1929. Thereafter the number of the established L.kaempferi increased remarkably. We believed that seed dispersal from artificial forests of L.kaempferi that have been planted since 20 years after the eruption, and from the individuals that had invaded in the very early period, contributed to the increase of L.kaempferi trees. L.kaempferi allocated more biomass to leaves than broadleaved trees and less to roots which, however, had a larger ratio of fine roots. Although almost all of the shoots of L.kaempferi survived the growing season, broadleaved trees showed considerably high mortality ratios of shoots. These traits enable L.kaempferi seedlings to establish and to growth favorably. We considered that broadleaved trees could have persisted their population by sprouting. From the results of examining water potential of trees, we regarded L.kaempferi as a drought-tolerant tree, which can maintain physiological ability even under the low water potential, however, P.maximowiczii can be regarded as a drought-avoiding tree which tend to retain high water potential to sustain favorable physiological activity
• Light regime and tree regeneration in scarified sites in forest stands

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research

  Date (from‐to) : 1996 -1997 

  Author : SHIBUYA Masato, MATSUDA Kyo, TAKAHASHI Kunihide

   

  Light regime and stand strucuture of 4 natural stands regenerating on scarified sites in mixed forest stands with various canopy closures were invsetigated in the Uryu and Nakagawa Experimental Forests of Hokkaido University. Light regime was affected by shading from canopy and was spatially heterogeneous, ranging from less than 10% to approximately 100% in RLI,in each site. Light conditon under the canopy was estimated roughly as 15-30% in RLI,and it around the canopy edge as about 40%. RLI on the center of a canopy gap reached to more than 80%. Species composition and structure of a regenerating stand were also affected by canopy distribution. In a canopy gap, pioneer trees such as birches dominated, though late-successional trees such as oak and conifers were mixed with birches or were dominant on occasion under and around the canopy.Therefore, a regenerating stand was composed of small patches of various species composition and structure. Trees with seed dispersed by birds occurred frequently. Height growth decreased with reduced light condition. This tendency was extremely obvious in birch. It is possible that a mixed stand regerates on a scarified site with the canopy of overstory trees.
• サイズ分布を考慮した林分の収穫予測について

  日本学術振興会：科学研究費助成事業

  Date (from‐to) : 1993 -1993 

  Author : 渋谷 正人

   

  天然生のシラカンバ林の林分調査を行い、今年度を含め、合計で73林分の林分データをえることができた。シラカンバは同齢単純林を形成する樹種であるので、林分密度管理は、競争-密度効果則に基づく解析が有効であると考えられ、樹高を因子とし、成長段階を規定し、林分成長にともなうC-D効果線のトレンドについて、現存量と蓄積の両方で検討した。その結果、C-D効果の逆数式のパラメータのうちAは、成長後期に一定となる傾向が、現存量と蓄積の両方でみられた。従来密度管理図では、逆数式のパラメータA、Bともに、樹高階に対し単純な相対成長式的関係で推定されており、本研究でえられた結果は、密度管理手法の再検討の必要性を示す結果と考えられる。またAが一定になることにより、密度管理図では無視されていた最終収量一定の法則が保証され、従来の生態学理論に照らし合わせても、この傾向は妥当であると考えられた。 サイズ分布は、個体材積分布について検討した。その結果、シラカンバ林における材積分布は、多くの林分で穂積のMNY法によって導かれた特殊ベータ型分布で近似できることがわかった。この分布型は、ひとつのパラメータ(A)で分布型が規定されるので、このパラメータと林分の成長段階や込み合い方との関係について検討し、込み合い方との関係からこのパラメータを推定できることが明かとなった。その結果、林分の成長段階と込み合い方から、平均材積、密度、材積分布を予測できるモデルが構築でき、実際の材積分布のデータにも比較的よく適合するようであった。さらに林分毎の樹高-胸高直径関係について検討し、その結果と予測される材積分布から、樹高と胸高直径分布を逆に構築し、これらのサイズの分布についても、予測モデルを構築した。
• 天然生カンバ林の樹冠層内の照度の変化と枝の枯れ上がり

  日本学術振興会：科学研究費助成事業

  Date (from‐to) : 1992 -1992 

  Author : 渋谷 正人
• FOREST DISTURBANCE BY THE 1926 MUDFLOW AND REVEGETATION PROCESSES AT MT.TOKACHI VOLCANO

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research

  Date (from‐to) : 1991 -1992 

  Author : YAJIMA Takashi, NAKAMURA Futoshi, SHIMIZU Osamu, SHIBUYA Masato

   

  The 1926 mudflow at Mt.Tokachi Volcano created a vast, bare land mass with heterogeneous and edaphic conditions. Forests were regenerated mainly by seedings supplied from remaining vagetation islands and surrounding areas. Vagetative regrowth was possible in downstream and boundary areas of the mudflow where forests suffered light damage. Revegetated forests display a mosaic structure, consisting of small or large elongated patches. Atands can be classified by dominant soecies, such as Picea glehnii, P.jezoensis, Abies sachalinensis, and betula spp. Pure Betula stands are found at the boundary areas of the mudflow where fine sediment was deposited. Picea glehnii stands were established in the central areas of bounder-rich soil deposits. Dwarf bamboo(Sasa spp.) dominated the floor of Betula stands, and it is likely that its rapid recovery playd an important role in forming Betula stands. Soil analysis clearly indicated the strong linkage between edaphic conditions and stand types. We concluded that differences in atand structures of revegetated forests could be attributed the heterogeneous site conditions created by the mudflow.
• Clarification of Factors Inhibiting Regeneration of Glehn's spruce (Picea glehnii) at the Initial Stage of Natural Regeneration

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research

  Date (from‐to) : 1990 -1992 

  Author : IGARASHI Tsuneo, SHIBUYA Masato, HAYASHIDA Mitsuhiro, NATSUME Shunji, FUNAKOSHI Saburo

   

  Research was conducted on factors preventing natural regeneration of the Glehn's spruce (Picea glehnii) at early stages of growth, such as fungi, field mouse, moisture in forest floor and photoenvironment. Analysis of the environment where natural seedlings grow was also conducted. Six species of filamentous fungi were separated from Glehn's spruce seeds which had passed the winter under the forest floor. Among those, Racodium therryanum, which rotted the seeds, and Rhizoctonia solani and Fusarium rosume, which dumping-off the seedlings, are the significant types of fungi. While seeds are often eaten by fiels mouse in forest thicks with Sasa, the number of seeds eaten decreased on bare land where the ground had become exposed due to surface scraping. By removing Sasa by surface scraping, the activity of field mouse was limited and the survival rate of seeds was jmproved. Regarding the seasonal changes of water content in the soil, it changed sharply in the L layer, from 10 to 70%. It was found that seeds above the L layer were prone to dehydrate and die. As for photoenvironment, it was found that more than 30% relative illumination was necessary for sufficient growth of seedlings and planted Glehn's spruce trees. Natural seedlings of the Glehn's spruce grow on mossy forest floors, fallen trees, mounds, stumps and bare land. Surface scraping of small areas in the forest is thought to be effective for hastening natural regeneration.
• 天然生カンバ林における密度の変化と保育技術に関して

  日本学術振興会：科学研究費助成事業

  Date (from‐to) : 1991 -1991 

  Author : 渋谷 正人
• シベリアタイガ林の林分動態と山火事の影響
• 林分内の個体間競争
• Stand dyhamics of larch stands in Siberian taiga and effect of forest fire on their dynamics
• Competition effect in forest stands.