In the eastern and middle San-in districts, on the southern coast of the Western Japan Sea, the following floral change is recognized since the middle Pleistocene.
There were three types of flora during the middle Pleistocene. First was the interglacial flora composed of cool temperate forest elements such as Fagus crenata, Quercus sp., Cryptomeria japonica, etc., and a pollen assemblage which is predominated by Fagus or represented by Fagus and Cyptomeria. Second is the glacial flora composed of subarctic elements as Picea jezoensis, Tsuga diversifolia, Menyanthes trifoliata, etc., and pollen assemblage represented by Pinus Subgen Haploxylon and Picea. Third is the interstadial flora composed of pollen assemblages represented by Picea and Cyptomeria.
During the late Pleistocene, a fourth type of flora appeared, composed of warm temperate forest elements with pollen assemblages containing Cyclobalanopsis. Moreover, some species occur in each type of flora: Pinus koraiensis occurs in glacial flora, Lagerstroemia pollen in interglacial and Buxus microphylla var. japonica and Pseudotsuga japonica in interstadial. By means of pollen analysis, the latest Pleistocene and Holocene pollen zones are clearly identified as follows.
Quercus and Alnus PZ: before about 10, 000y.B.P.
Quercus and Aphananthe-Celtic PZ: about 10, 000 to 9, 000y.B.P.
Fagus and Tsuga PZ: about 9, 000 to 7, 000y.B.P.
Pinus and Abies PZ: about 7, 000 to 5, 500y.B.P.
Cyclobalanopsis and Castanopsis PZ: about 5, 500 to 2, 400y.B.P.
Gramineae PZ: about 2, 400y.B.P. to present
Cryptomeria Subzone: about 2, 400y.B.P. to about A. D. 700
Typical Subzone: about A. D. 700 to 1, 500
Pinus Subzone: about A. D. 1, 500 to later than 1, 900
Pinus and Cyptomeria Subzone: later than A. D. 1, 900 to present.

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福井県中池見の堆積物は下部砂礫層と上部有機質層に二分され，上部有機質層は阿多（Ata），鬼界葛原（K-Tz），姶良Tn（AT），鬼界アカホヤ（K-Ah）などの火山灰をはさむ後期更新世以降の有機質に富んだシルトである。堆積盆中の北部2地点，中央部1地点，南部2地点において，上部有機質層のATより下位について花粉分析を行い，盆地および周辺における植生分布の様式を復原し，環境変遷を議論した。上部有機質層は堆積盆中央部で堆積がはじまり，全般にスギ属花粉が優占する。北部ではスギ属花粉に伴ってコナラ属コナラ亜属花粉が産出し，中央部ではハンノキ属花粉が多く，南部ではスギ属花粉が優占することから，北部の山地にはコナラ亜属の森林が，中央部にはハンノキ湿地林が，南部の谷筋にスギ林が復原される。約8万年前には，湖沼が南部にまで広がったクリ属／シイノキ属花粉が優占する時代と，落葉広葉樹花粉が産出する時代とがあり，その後，湖沼が北部に広がった。約5万年前にアジサイ属花粉が一時的に多産し，これを境にハンノキ属とミズバショウ属花粉が増加し，コウヤマキ属花粉の減少とヒノキ科花粉の増加が見られる。堆積物にも有機物が増え，中央部と南部を中心に湖沼環境が卓越していたのが，堆積盆全体にハンノキ林が広がった。AT降下前には，最終氷期最盛期へ向かう寒冷乾燥化を示唆するようにツガ属や，マツ属，カバノキ属花粉が増加し，中央部はカヤツリグサ科を中心とする湿原となった。

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The purpose of the present study is to obtain basic infomations on the relations between the air-borne pollen and the living vegetation surrounding the air-borne pollen collector.
Ten stations were selected to collect air-borne pollen (Figure 2).
The air-borne pollen which were caught on one square centimeter of a slide glass smeared with petrolatum-oil was observed from 13 March to 4 August, 1971. The slide was set at a point at each station, kept out of the rain, and replaced by new one each week.
The results are given in Figures 3 and 4. Pollen detected through all stations amount to one family and 36 genera of tree pollen and 10 families and 6 genera of herbaceous pollen and a spore. About 97per cent of the total pollen detected in this study was dispersed in the atmosphere during period from middle March to early June. Planted trees (Cryptomeria and Pinus) occupied over 87per cent except stations 1, 2 and 3.
Fagus was found in small quantities (1-2%) at stations 6, 7, 8, 9 and 10 in spite of the absence of the living beech. This pollen was derived by the wind from montane zone dominated by F. crenata being about 40km from these stations.
Abies, Tsuga and Betula were detected 6-16 grains through all stations. These trees are scarcely found in the area studied, although found in the subalpine zone of Mt. Zaô. Abies, Tsuga and Betula were probably carried by the wind for a long distance (about 40-60km).

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本州中部,長野県北部に分布する高野層は,上部更新統のテフラ立山D(Tt-D),御岳第1(On-Pm1),鬼界葛原(K-Tz),阿蘇4(Aso-4),御岳奈川(On-Ng),立山E(Tt-E),大山倉吉(DKP)および姶良Tn(AT)を挾在する.同層の花粉群の層位的変動に基づき,下位より局地化石花粉群帯TKN-I～VIII帯を設定した.この花粉帯を,野尻湖,諏訪湖など近隣の花粉帯と広域テフラを鍵層として対比し,地域的な環境変遷を明らかにした.Aso-4を挾むTKN-IV帯,Tt-E,DKPを挾むTKN-VII帯は,マツ科針葉樹やカバノキ属花粉が優占する寒冷な気候,Tt-Dを挾むTKN-II帯,On-Ngの直上のTKN-V帯,DKPの上位のTKN-VIII帯は,温帯性落葉広葉樹花粉が優占する温暖な気候,最下部のTKN-1帯,On-Pm1,K-Tzを挾むTKN-III帯,Tt-Eの下位のTKN-VI帯は,スギ属,ヒノキ科花粉が多く,降水量の多い冷涼な気候を示唆する.DKPの降灰期はMIS3/4境界,すなわち約58～59kaより古くなる可能性が指摘できる.

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Paleovegetation and palaeotemperature at 1160 m a.s.l. at the southeastern foot of Mt. Yatsugatake were reconstructed based on plant macrofossil assemblages from fluvial deposits in two horizons a sand layer intercalating the Blue Glass tephra deposited around MIS7.3 of the late Middle Pleistocene. A deciduous broadleaved forest grew near the study site, and a pinaceous conifer forest spread in upstream areas at higher altitudes. Plant macrofossil assemblages included taxa distributed mainly in the warm-temperate zone, such as Selaginella remotifolia, Buxus microphylla, and Phytolacca japonica. The annual mean temperature at the site of fossil deposition was estimated to be slightly warmer than that at the present (7.8°C) from the coldest limit of distribution ranges of Phytolacca japonica (8.5°C) and Selaginella remotifolia (8.1°C).

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