著者

杉田 久志

出版者

日本生態学会

雑誌

日本生態学会誌 (ISSN:00215007)

巻号頁・発行日

vol.38, no.3, pp.217-227, 1988-12-31

被引用文献数

10

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At higher elevations on Mt. Asakusa, one of the mountains characterized by deep snow accumulation in Japan, the relationship between snow depth and the distribution pattern of plant communities was studied in connection with topographical conditions. Dwarfed Fagus crenata forests in the northwestern〜western part (N〜W slope), and scrubs and meadows in the southern〜eastern part(S〜E slope). The snow depth in meadows was the deepest among the four plant communities, and that in scrubs was deeper than those in Fagus crenata forests and dwarfed Fagus crenata communities. However, little difference in snow depth was found between Fagus crenata forests and dwarfed Fagus crenata communities. Therefore, it is difficult to explain the distribution of plant communities only by the snow depth. It is presumed that topographical conditions affect not only the distribution of snow depth but also the effects of the snow on plants, and that consequently the distribution pattern of plant communities is determined through the influence of the topography.

著者

塚田 松雄

出版者

日本生態学会

雑誌

日本生態学会誌 (ISSN:00215007)

巻号頁・発行日

vol.31, no.4, pp.371-383, 1981-12-30

被引用文献数

1

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A theoretical examination of pollen dispersal suggests that : (1) in a forested region containing about 40% Cryptomeria japonica trees, 5.0% Cryptomeria pollen is found ca. 10 km away from the source forest ; and (2) an increase to 5.0% from a lower percentage indicates the actual arrival of trees sparsely distributed in the forest within 500 m. After its initial arrival, the Cryptomeria forest shows a logistic increase under climatically near optimal growing conditions. The standard empirical equation for this increase is expressed by p=50.0/(1+14.16 e^<-0.0014t>), where p is Cryptomeria pollen percentage at time t (yr). Combined pollen frequencies against time that are obtained from six bogs become scattered at higher levels, since the carrying capacity for the population is variablea among these sites. However, sigmoid curves of the Cryptomeria increase toward respective asymptotes are essentially identical from the initial rise up to the 25% level. It normally takes about 1,000 years for pollen percentages to increase from 5% to 10%, and an additional 1,500 years to reach ca. 35%. The fact that Cryptomeria increases logistically implies indeed that even when its pollen percentage is low at the beginning of the rise, climatic conditions must already be favorable for maximum growth of the species.

著者

三好 教夫 波田 善夫

出版者

日本生態学会

雑誌

日本生態学会誌 (ISSN:00215007)

巻号頁・発行日

vol.27, no.4, pp.285-290, 1977-12-30

被引用文献数

1

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Makura moor is situated at the place of 720 m above sea level at Geihoku-cho within the Chugoku Mountains, in the northern part of Hiroshima Prefecture. From the results of pollen analysis, four major vegetational changes for approximately the last 10,000 years were recognized in the pollen diagram from the bottom to the surface. 1. Tsuga, Pinus (Haploxylon type), Picea, Betula stage (190-170 cm, 10,000-9,000yr B.P.) (R-I zone). 2. Cyclobalanopsis, Lepidobalanus, Alnus stage (170-80 cm, 9,000-4,000yr B.P.) (R-II zone) 3. Lepidobalanus, Cyclobalanopsis, Alnus stage (80-60cm, 4,000-1,500yr B.P.) (R-IIIa zone) 4. Pinus (Diploxylon type), Cryptomeria, Lepidobalanus stage (60-0 cm, after 1,500yr B.P.) (R-IIIb zone) The vegetational history can be regarded as the common one for the period from the postglacial age to the present time in the Chugoku Mountains, with one exception of Cryptomeria, the number of pollen of which is included in low percentage in the second and third stage compared with the results of another moors, such as Yawata moor, Sugawara moor, Kabosaka moor and etc.

著者

高原 光 竹岡 政治

出版者

日本生態学会

雑誌

日本生態学会誌 (ISSN:00215007)

巻号頁・発行日

vol.36, no.2, pp.105-116, 1986-08-31

被引用文献数

3

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The pollen analysis of core samples from the Hatchodaira moor (alt. 810m) in the montane zone at the northern part of Kyoto City, revealed seven vegetational changes to have occured there during the last 25,000 years. 1. Conifer・Betula stage (ca. 25,000-15,000 y.B.P.) : subarctic coniferous forest. 2. Fagus・Lepidodalanus-Conifer・Betula stage (ca. 15,000-12,000 y.B.P.) : the ecotone between subarctic coniferous and cool temperate broad-leaved forests. 3. Conifer・Betula stage (ca. 12,000-10,000 y.B.P.) : subarctic coniferous forest. 4. Fagus・Lepidobalanus・Betula stage (ca. 10,000-9,000 y.B.P.) : the ecotone between subarctic coniferous and cool temperate broad-leaved forests. 5. Fagus・Lepidobalanus・Carpinus stage (ca. 9,000-4,500 y.B.P.) : cool temperate beech (F. crenata) forest. 6. Lepidobanlanus・Carpinus・Betula stage (ca. 4,500-1,500 y.B.P.) : cool temperate oak (Quercus mongolica var. grosseserrata) forest. 7. Pinus stage (ca. 1,500 y.B.P.-present) : pine (P. densiflora) forest reflecting the destruction of natural forests by human activities.

著者

中川 尚史

出版者

日本生態学会

雑誌

日本生態学会誌 (ISSN:00215007)

巻号頁・発行日

vol.46, no.3, pp.291-307, 1996-04-25

被引用文献数

9

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Studies on food selection in non-human primates were reviewed from the viewpoint of optimal food selection. Key factors in the classical model of optimal food selection were "maximization" of the "intake rate" of "energy". Later, the key factors were changed to "maximization" of the "contents" of "energy-essential nutrients" and "minimization" of the "contents" of "digestion inhibitor-toxins" in a modified model for herbivores. Most studies on food selection in herbivorous non-human primates have been based on the modified model, and revealed that primates choose food so as to maximize protein, and to minimize digestion inhibitiors (fiber, condensed tannin). However, the present review points out that the above key factors of the classical model are also important because food availability relating these factors correlates positively with feeding frequency.

著者

大沢 雅彦 川那部 浩哉

出版者

日本生態学会

雑誌

日本生態学会誌 (ISSN:00215007)

巻号頁・発行日

vol.42, no.3, pp.275-282, 1992-12-10

著者

久保 拓弥

出版者

日本生態学会

雑誌

日本生態学会誌 (ISSN:00215007)

巻号頁・発行日

vol.59, no.2, pp.187-196, 2009-07

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観測データの背後にある生態学的なプロセスを特定するときに,データの空間構造に由来する空間的自己相関(空間相関) のある「場所差」はとりあつかいの難しい「ノイズ」である.空間相関のある「場所差」はrandom effects として統計モデルの中で表現するのがよい.近年よく使われているGLMM など簡単な階層ベイズモデルでは空間相関のあるrandom effects をうまくあつかえない.そこで空間相関をうまく表現できるintrinsic Gaussian CAR model の概要を説明し,単純化した架空データから得られる推定結果を示す.また階層ベイズモデルが威力を発揮する,欠測のある観測データが与えられた状況での推定結果も示した.