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走査電子顕微鏡(SEM)を用いて, コナラ属14種(アカガシ亜属7種コナラ亜属7種)について, 合計で113個体938粒の花粉について表面構造を観察した。その結果, アカガシ亜属花粉の表面微細構造には「微小刺」と「顆粒」が認められ, その形状は7種全てにおいて類似した形態を示した。また, コナラ亜属花粉の表面微細構造には, 線状の「突起」が全面に認められる形態(ウバメガシ), 「顆粒」が大きく盛り上がり, それが丸い形状を示す形態(ミズナラ, コナラ, ナラガシワ), 「顆粒」が大きく盛り上がり, それが尖った形状を示す形態(カシワ)および「顆粒」がやや盛り上がり, 花粉表面全体がしわ状になっている形態(アベマキ, クヌギ)が認められた。, Exine sculpture of 938 pollen grains from 113 specimens representing 14 Quercus species (7 species of subgenus Cyclobalanopsis and 7 species of subgenus Lepidobalanus) of Japan were examined by using SEM. On the exine sculpture of Quercus subgenus Cyclobalanopsis pollen, "microspine" and "granula" were recognized and those morphologies were similar among the 7 species. On the exine sculpture of Quercus subgenus Lepidobalanus pollen, the striae type (Q. phillyraeoides), the round granula type (Q. mongolica var. grosseserrata, Q. serrata, and Q. aliena), the sharp-pointed granula type (Q. dentate), and the cockled granula type (Q. variabilis, and Q. acutissima) were recognized.

筆者らは, 奈良県北東部の曽爾高原に位置するお亀池湿原の堆積物の花粉分析を行ない, 分析の結果にしたがって, 晩氷期から現在にかけての森林の変遷を考察した。その結果の概要は次のとおりである。1.堆積物の放射性炭素による年代は, 泥炭層の深度220∿230cmで, 3860±160y.B.P.(コード番号KSU-314)であった。また, 深度281∿284cmの火山灰層はアカホヤ火山灰からなっており, その年代は6000∿6500y.B.P.であった。2.晩氷期から現在にかけて, 次のように6回にわたって森林型に変化のあったことが認められた。1) Abies・Tsuga・Pinus-Betula時代2) Fagus・Lepidobalanus・Carpinus時代3)Abies-Lepidobalanus時代4) Abies-Castanea時代5) Cyclobalanopsis-Abies時代6)Pinus時代1)は亜寒帯性針葉樹林の時代, 2)は冷温帯落葉広葉樹林の時代, 3)・4)は中間温帯林の時代, 5)は暖温帯常緑広葉樹林の上部に位置する時代, 6)は人類の影響を強く受けたマツ林の時代である。, The writers carried out pollen analytical study of the Okameike peat deposits in the Soni plateau located north eastern part of Nara, and from the results attained was able to visualize the historical changes in the forests since the Late glacial period. The summary of the results are as follows. 1. The ^C date of peat at 220-230cm levels was 3860±160y.B.P. (code NO. KSU-314). Volcanic ash layer at 281-284cm was the Akahoya ash erupted from the Kikai caldera between 6000 and 6500y.B.P. 2. Six forest stage were recognized in the vegetational history since the Late glacial period : 1) Abies・Tsuga・Pinus-Betula stage 2) Fagus・Lepidobalanus・Carpinus stage 3) Abies-Lepidobalanus stage 4) Abies-Castanea stage 5) Cyclobalanopsis-Abies stage 6) Pinus stage The first stage is characterized by the dominance of the subarctic forest elements. This stage, therefore, corresponds to the Late glacial period. The second stage is dominated by the cool temperate forest elements. The third and the fourth stage are characterized by the increase of Abies that mainly constitutes the temperate ecotne forest. In the fifth stage, the warm temperate forest element, Cyclobalanopsis becomes dominant. It seems that this stage was situated in upper part of the warm temperate forest zone. The dominance of Pinus in the sixth stage reflects the destruction of natural forests by human activities.