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The two aims of this study were, firstly, to investigate the total number of trees, tree height, diameter at breast height (DBH), tree age, and tree distribution in a Fukugi (Garcinia subelliptica ) forest in Shiokawa-utaki, where the artificially planted Fukugi tree is dominant, and to investigate the history of this tree plantation. Secondly, we applied a phytosociological approach to compare the characteristics of a man-made Fukugi plantation in Shiokawa-utaki and an artificial forest and a natural forest in the Futenma-utaki on the coastline. In Shiokawa-utaki and along the entrance path leading to it, 2,457 woody trees were found, with approximately 70% being Fukugi trees. The oldest of these was estimated to be 248 years of age. The proportion of young Fukugi trees was high, with 85% of them being younger than100 years of age. The reason for this small proportion of 100 year-old trees may be the continuous natural regeneration during the course of establishing this plantation. In particular, the distribution chart of the tree age demonstrates that the somayama (government administered timber forest) governance reinforcement of 1742 during the reign of the Ryukyu Kingdom and damage from the Meiwa tsunami in 1771triggered the development of the Fukugi tree plantation. When examining the distribution chart of the Fukugi trees in Shiokawa-utaki, we found that old-growth trees occur at the outer periphery of the ground, with the spirit rock in the center. This indicates that the Fukugi forest was initially planted from the outer periphery of the utaki grove. Our phytosociological examination found that the Fukugi forest in Shiokawa-utaki can be classified as a Diospyros egbert-walkeri-Garcinia subelliptica community, consisting of differential species like Diospyros egbert-walkeri, Flagellaria indica and Paederia scandens. The Calophyllum inophyllum forest in Futenma-utaki can be classified as an Antidesma pentadrum-Calophyllum inophyllum community that consists of differential species like Calophyllum inophyllum, Antidesma pentandrum, Callicarpa japonica var. luxurians, and Ficus erecta. The natural Hernandia nymhaeaefolia forest in Futenma utakican be classified as an Allophylus timorensis-Hernandia nymhaeaefolia community, consisting of differential species like Hernanida nymhaeaefolia, Allophylus timorensis, Euonymus japonicus and Planchonella obovata. It can be assumed that the Fukugi forest in Shiokawa-utaki and the artificially planted Calophyllum inophyllum in Futenma-utaki have developed by replacing an original Psychotria manillensis-Diospyros maritima natural forest alliance., 紀要論文

天然林の成長動態の解析は、天然林資源を管理する上で不可欠である。 北海道有林北見経営区内に天然林を対象に設定した固定標準地を40年ぶりに調査を実行し、針広混交天然林の成長動態を解析した。解析の結果、樹木本数が大幅に減少している反面で蓄積が大幅に増加していることがわかった。本数が減少したのは主として広葉樹である。一方、林分の材積成長にはエゾマツ、トドマツが大きな影響を与えるため、本数が減少したにも係わらず、林分材積成長量は40年間で大きくなったことが分かった。材積の40年間の粗成長量は326.1m3/ha、純成長量は243.8m3/haである。, The analysis of growth dynamics in natural forest is indispensable for managing natural forest resources. Growth dynamics was analyzed for the permanent plot of natural forest for forty years in the Hokkaido Prefectural Forest of Kitami district. The result of analysis showed that stand volume was increasing sharply, while the total number of trees were decreasing for forty years. Main decreasing species were broadleaf trees. Volume of spruce and fir was shown a accounts for the big rate of total stand volume increments. Therefore, stand volume increments was increasing for forty years. Gross volume growths was 326.1m^3/ha for forty years and net volume growth was 243.8m^3/ha for forty years.

この研究は, 亜熱帯沖縄における森林植物の希少植物等の探索・収集・保存・増殖に関する研究の一環として, 石垣島於茂登岳山麓において自生が確認されたサキシマスオウノキ(Heitiera littoralis)林を対象に生育木の現状および生育地の植生を明らかにしたものである。調査の結果は次のとおりである。1. サキシマスオウノキは通常マングローブの後背湿地や海岸付近に分布する。しかし, 石垣島於茂登岳山麓の宮良川上流底原の沢沿い(標高50∿80m)にもサキシマスオウノキが分布することが明らかになった。2. 於茂登岳山麓のサキシマスオウノキは, 沢沿いでほとんどが礫の堆積地に分布していた。3. 現在, サキシマスオウノキは流域全体で174本の生育が確認され, そのうち5本は折損木であった。また, 10個の切り株が確認された。4. この流域で樹齢が最も古いものと推定されるサキシマスオウノキが3本確認された。しかし, 一本は健全に生育しているが, 他の2本は地上高1.70mで伐倒され, そのうち1本は枯死し, 残りの1本は萌芽していた。5. 本群落はサキシマスオウノキを優占種とし, 湿地∿湿潤地性の種と多くの山地性の種を構成種とする特異な植生であることが明らかになった。特異な立地に成立する要因についていくつかの考察を行ったが, これについては今後の課題である。6. 於茂登岳山麓のサキシマスオウノキは西表島の古見の群落に比べて, 標高の高い特異な立地に群落を形成することから, これらがどのように定着し, 林分を形成したのか非常に興味深く, これらの更新動態についてさらに研究を進めていきたい。7. 石垣島於茂登岳山麓のサキシマスオウノキは, 特異な例として内陸部に分布することから石垣市の天然記念物に指定すべきであろう。さらに将来は, 沖縄県あるいは西表島のサキシマスオウノキと同様に国指定の天然記念物に指定すべきであろう。, The state of growth of Heritera littoralis, natural colonies, which were discovered at the foot of Mt. Omoto on Ishigaki Island, and the vegetation at sites of its growth were studied as part of research concerning the exploration, collection, preservation, and proliferation of rare plants in subtropical forest of Okinawa. The following results were obtained. Heritiera littoralis is usually distributed in mangrove swamps and coastal areas. However, it was found to be distributed also along the streams in Sokobaru (altitude 50-80) upstream of the Miyara River at the foot of Mt. Omoto, Ishigaki Island. Heritiera littoralis at the foot of Mt. Omoto was distributed along the stream mostly in gravel deposits. To date, 174 growths of Heritera littoralis have been confirmed in the entire river basin, and 5 of them were damaged. Also, 10 stumps have been confirmed. Three growth of Heritera littoralis estimated to be the oldest in the river basin have been identified. One was growing intact, but the other two were cut at a high of 1.70m from the ground. One them were dead, and the other was budding. Heritiera littoralis was dominat in the tree layer of two stands, which was chracteristic vegetation consist of many species in the forest of back mangrove and inland. It showed some considerations on the cause where the stand had grown at the foot of Mt. Omoto, it should be studied in future. The colonies of Heritiera littoralis at the foot of Mt. Omoto grew at a higher attitude than the colonies in Komi, Iriomote Island. Therefore, the processes of their distribution and formation of forest stands are extremely interesting, and further studies on the dynamics of their changes are needed. Since Heritera littoralis at the foot of Mt. Omoto on Ishigaki Island shows unique inland distribution, it should be designated as a natural treasure of Ishigaki City. It should further be designated as a natural treasure of the nation similarly to Heritiera littoralis of Okinawa Prefecture or Iriomote Island., 紀要論文

この研究は, 亜熱帯沖縄における森林植物の希少植物等の探索・保存・増殖に関する研究の一環として, 石垣島平久保のヤエヤマシタン(Pterocarpus indicus)林を対象に生育木の現状および生育地の植生調査を行ったものである。調査の結果は, 次のとおりである。1. 平久保のヤエヤマシタンは, 1972年5月15日に国の天然記念物に指定された。2. 現在, ヤエヤマシタンは石垣島で自生木, 栽培木を合わせて78本の生育が確認された。3. 平久保では, 現在の天然記念物の2個体の他に, 1991年7月に胸高直径20cm, 樹高11.5mの1本, 今回新たに胸高直径13cm, 樹高8mの幼齢樹が確認された。4. これまで, 1莢当たりの種子数は1個とされているが, 1∿4個の種子が含まれていることことが明らかとなった。5. 376莢のうち1莢当たりの種子数の出現頻度は, 1粒莢が43%, 2粒莢が39%, 3粒莢が17%, 4粒莢が1%で, 1粒莢が最も多かった。6. 種子の発芽は, 1粒莢の種子では播種後2日目から7日目に発芽がみられ播種後4日目と6日目に3粒ずつの最大発芽がみられた。7. 天然記念物2個体のうち1個体は幹および根が, 他の個体は根がそれぞれ削り取られており, 傷跡は深く, いずれの切り口も腐朽しており, 早急に損傷部の回復をはかる必要がある。8. 林分は自然林に人為干渉を受けて変質しているが,低地帯森林植生のリュウキュウガキーナガミボチョウジ群団に属するヤエヤマシタン群落と考えられる。, As a part of studies on the research for preservation, reproduction of rare forest plants in subtropical Okinawa, we examined the present status of growth trees and vegetation in the habitat in a Yaeyamashitan (Pterocarpus indicus) forest in Hirakubo on Ishigaki Island. The following results were obtaind. 1. Yaeyamashitan in Hirakubo was designated as a national treasure in May 15,1972. 2. Growth of 78 spontaneous trees and cultivars was confirmed on Ishigaki Island. 3. In Hirakubo, in addition to 2 trees as a national treasure, 1 tree (diameter at breast height, 20cm; tree height, 11.5m) and 1 young growth (diameter at breast height, 13cm; tree height, 8m) were confirmed in July, 1991 and December 1994,respectively. 4. Though the number of seeds per legume had been considered to be 1,1∿4 seeds per legume were observed. 5. One seed/legume was observed in 43% of 365 legumes, 2 seeds/legume in 39%, 3 in 17%, and 4 in 1% the incidence of 1 seed/legume was the highest. 6. Germination of seeds occurred 2∿7 days after seedling in 1 seed legumes, and maximum germination of 3 seeds each was observed 4 days and 6 days after seedling. 7. Of the trees as a national treasure, 1 showed cuts in the trunk and root, and the other showed cuts in the root. This damage was deep, and each cut surface was decayed. Restoration of the damage parts is urgently necessary. 8. The forest stand is considered a Pterocarpus indicus community of Diospyros maritima-Psychouia manilensis alliance in the lowland vegetation. Though the vegetation has been changed by the human disturbance., 紀要論文

京都大学北海道演習林白糠区固定プロット14箇所計2.8haについて、1976年の設定時から1997年の第5回測定時にかけての21年間の成長率の平均と分布を検討した。その結果、haあたり平均蓄積は261.4m[3]から299.2m[3]へと増加しており、プレスラー式による成長率は0.6%であった。これは、京都大学北海道演習林長期施業計画第一次計画において白糠区天然林成長率の暫定値として採用されている1.0%よりも低い数値である。針広別の成長率は、トドマツ成長率のプロット平均が1.5%に対し、広葉樹成長率は0.0%であった。つまり、広葉樹については成長が観察されず、トドマツの成長度合いに全体の成長率が左右されていることがわかった。広葉樹については、成長率に関するファジィメンバシップ関数の検討を行った。広葉樹の成長率を林班別に検討した結果、6林班については「ほとんどゼロである」(平均0.0%)、4林班については「ある程度の成長が見込まれる」(平均0.4%)、8林班は「変化の幅が大きく、全体にマイナス成長が見込まれる」(平均-0.6%)との総合評価を行い、それぞれのメンバシップ関数を例示した。, The average and distribution of annual growth rate of natural forests of Kyoto University Forests in Hokkaido (Shiranuka District) were analyzed using the continuous inventory on 14 permanent plots with a total area of 2.8ha. Average volume per ha changed from 261.4m[3] in 1976 to 299.2m[3] in 1997 and the annual growth of 0.6% rate was calculated by Presssler Method. The rate was less than 1.0% which was temporally used as the annual growth rate for natural forests in the Long-Term Forest Management Plan of Kyoto University Forests in Hokkaido (1987-1996). The annual growth rate classified by forest type was 1.5% for coniferous trees (Abies sachalinensis) and 0.0% for broad-leaved trees, respectively. Namely, the total growth rate mainly depends on the presence of Abies sachalinensis. For broad-leaved trees, the characteristics of the growth rate were analyzed. As an overall estimation, it was shown that the growth rate is approximately zero in Compartment 6 (average=0.0%), some degree of growth will be probable in Compartment 4 (average=0.4%), and minus growth will be probable with a large bias in Compartment 8 (average=-0.6%). In these estimations, fuzzy membership functions are exemplified.

本研究は, 西表島における天然林の樹種の分布, 資源量および資源植物学的分類を明らかにしたものである。その結果を要約すると次のとおりである。1 森林資源調査における出現樹種は90種であった。樹種別の本数分布率はイタジイ13%, タブノキ6%, リュウキュウマツ6%, エゴノキ5%, シャリンバイ3%, モクタチバナ 3%, リュウキュウモチノキ3%, エゴノキ3%, ハゼノキ3%, リュウキュウガキ3%, オキナワウラジロガシ3%の順であった。ha当たり100本以上のこれら8種で全本数の約28%を占め, 残りの約72%は82種で占められている。2 このように, 構成樹種の多様性が西表島における天然林の特徴である。3 森林資源調査の推定誤差率は, ha当たり本数9.8%, ha当たり材積9.1%であった。ha当たりの本数および材積は, それぞれ約3,730本, 約114m^3であった。4 資源植物学的分類は, 経済植物88種, 未経済植物2種であった。5 用途の民族植物学的分類は, I類では用材88種, 燃料47種, 食用19種, 薬用11種, 肥料11種, 染料11種, 飼料8種, 油脂6種, 繊維5種で, II類では観賞45種, 防風32種, 防風18種, 街路18種であった。III類の構成樹種は35種であった。6 林木の遺伝子資源はすべてB_2タイプの潜在的遺伝子資源であった。Cタイプの特定植物群落は15件であった。, The present study clarified the distribution, productivity and classification of economically important forest trees of natural forest in the lriomote Island. The results of the study are summarized as follows : 1. The number of species found out from the forest resources inventory was 90. The percentages of the number of trees by species were 13% of Castanopsis siebldii, 6% of Persea thunbergii, 6% of Pinus luchuensis, 5% of Styrax japonicus, 3% of Raphiolepis indica, 3% of Ardisia sieboldii, 3% of Ilea likuiuensis and 3% of Quercus miyagi. These 8 species which counted over 100 trees per hectare were about 28% of the whole of number of trees, and the remaining 72% was the other 82 species. 2. Therefore, the important charactristrics of the natural forest in the lriomote Island are the diversity of tree species. 3. The estimated rates of error in the forest resources inventory were 9.4% of number tree per hectare and 9.1% of volume per hectare. The number of tree and volume per hectare were 3,727 and 114m^3,respectively. 4. The classification of economically important forest trees were 88 species of exploited plant and 2 species of underexploited plant. 5. The ethnobotanical classification of forest trees by use were 88 species of lumber, 47 species of fuel, 19 species of food, 11 species of dye, 11 species of fertilizer, 11 species of drug, 8 species of forage, 6 species of oil and 5 species of fiber in the first group, and 45 species of yard, 32 species of wind, 18 species of street and 18 species tide in the second group. 6. The classification of genetic resources of forest trees were all the unutilized genetic resources of B_2 type. The number of special plant community of C type was 15., 紀要論文

本研究は, 亜熱帯沖縄における天然林の資源植物学的研究の一環として, 宮古島を対象に森林植物を中心とした資源植物の分布および用途別の分類を行い, 今後の資源植物の収集・保存・増殖および開発・利用を進めていく上での基礎的な資料を得るために行ったものである。調査の結果は次のとおりである。1. 森林資源調査における出現樹種は28種, 樹種別の分布率はCasuarina equisetifoliaモクマオウ38%, Cinnamomum pseudo-pedunculatumヤブニッケイ17%, Pinus luchuensisリュウキュウマツ11%, Acacia confusaソウシジュ6%, Eurya emarginataハマヒサカキ5%, Pongamia Pinnataクロヨナ4%, Diospyros maritimaリュウキュウガキ3%, Hibiscus tiliaceusオオハマボウ3%, Melanolepis multiglandulosaヤンバルアカメガシワ3%の順であった。樹種構成は, 主要島嶼の沖縄島, 石垣島, 西表島に比べて少なく, 単調であった。2. 森林資源調査の推定誤差率は, 平均胸高直径16.4%, 平均樹高11.7%, ha当たり本数26.1%, ha当たり胸高断面積19.1%, ha当たり材積25.3%であった。平均胸高直径および平均樹高は, それぞれ11.0cm, 6.4mであった。ha当たりの本数, 胸高断面積および材積は, それぞれ2,077本, 19.4m^2,76.7m^3であった。3. 宮古島の分布植物は, 在来植物が131科, 405属, 603種で, 外来植物が25科, 64属, 81種であった。そのうち在来植物は広く海外の熱帯地域に分布する植物が120科, 360属, 518種, 国内に限定されて分布する植物が50科, 80属, 85種であった。4. 宮古島と周辺近隣地との在来植物の共通種は, 石垣島563種(93.4%), 西表島559種(92.7%), 沖縄島555種(92.0%)で, 宮古島の約93%の植物が近隣地域に分布している。5. すでに開発・利用されている経済植物は121種で, 全体20%, 未利用・未開発の未経済植物は482種で全体の約80%を占め, 未経済植物は経済植物の約4倍も豊富に自生している。, 6. 経済植物は, I類, II類, III類の3グループに分類され, それぞれI類32科, 56属, 60種, II類22科, 25属26種, III類24科, 30属, 35種を構成した。7. 用途の民族植物学的分類は, I類とII類で, それぞれ17,7のカテゴリーに分類された。そのうち, I類の主なカテゴリーは用材26種, 薬用14種, 飼料9種, 食用9種, 肥料3種であった。8. 最近, 森林資源の新しい利用法として, 森林バイオマスの活用, 低利用・未利用広葉樹および林床植生の利用について検討が始められている。未利用植物の多い宮古島においても新しい活用・利用法の開発が望まれる。, Within the frame work of a series of plant resource studies on the natural forests in the subtropical Okinawa Islands, the present study was undertaken to investigate the distribution of resource plants (focusing primarily on the forest plants in Miyako Island), and to classify the plants by their application and use, with the goal of collecting basic data to be used in collection, preservation, cultivation, development and utilization of plant resources for the future. The following results were obtained. Twenty-eight plant species were confirmed in the forest inventory survey. The most frequent species found in the total forest area were distributed as follows : Casuarina equisetifolia 38%, Cinnamomum pseudo-pedunculatum 17%, Pinus luchuensis 11%, Acacia confusa 6%, Eurya emargionata 5%, Pongamia pinnata 4%, Diospyros maritima 3%, Hibiscus tiliaceus 3%, and Melanolepis multiglandulosa 3%. The number of tree species in Miyako Island was smaller than that on other majors islands constituting the Okinawa Islands (Okinawa Island, Ishigaki Island, Iriomote Island). Thus, the tree species were relatively mono tonous on Miyako Island. In this forest inventory survey, the sampling error is estimated to be 16.4% for the mean diameter at breast height, 11.7% for the mean tree height, 26.1% for the number of trees per hectare, 19.1% for the basal area per hectare, and 25.3% for the volume per hectare. The mean diameter at breast height was 11.0cm. The mean tree height was 6.4m. The number of trees per hectare was 2,077. The basal area per hectare was 19.4m^2 and the volume per hectare was 76.6m^3. In Miyako Island, 603 indigenous plant species, belonging to 405 genuses of 131 families, and 81 introduced plant species, belonging to 64 genuses of 25 families, were confirmed. Of the indigenous plants, 518 species (360 genuses of 120 families) are known to be dis tributed widely in foreign tropical areas, and 85 species (80 genuses of families) occur only in Japan. The indigenous species commonly found in Miyako Island and the neighboring islands were investigated. Of all species found on Miyako Island, 563 (93.4%) also occurred on Ishigaki Island, 559 (92.7%) on Iriomote Island and 555 (92.0%) on Okinawa Island. Thus, about 93% of the species found Miyako Island were also found in the neighboring island. Of all species found in Miyako Island, 121 (about 20%) are plants that have already been exploited, and 482 (about 80%) are unexploited plant.\n Thus the number of unexploited plant species was about 4 times that of the exploited ones on this island. The exploited plant were divided into three groups (I, II and III) according to their uses. Group I contained 60 species (56 genuses of 32 families), Group II 26 species (25 genuses of 22 families) and Group III 35 species (30 genuses, of 24 families). The plant were divided into Group I and II, according to their ethnobotanical classification. Group I and II were subdivided into 17 and 7 categories, respectively. The major categories in Group I were timber (26 species), medicine (14 species), forage (9 species), food (9 species), and fertilizers (3 species). In recent yeas, new ways of utilizing forest resources such as utilization of forest biomass, hitherto poorly utilized or unutilizedbroad-leaf tree and ground plant have been studied. It is desirable that new methods of making use of the previously unutilized plant abundantly found on this island be developed., 紀要論文