The EcologicalSocietyEcological Society ofJapanof Japan
Vol. 23, No. 4 JAPANESEJOURNAL OFECOLOGY Aug.,1973
HISTORICAL AND ECOLOGICAL STUDIES OF ABIES IILIRIESll' ON
MT. GASSAN, THE DEWA MOUNTAINS, NORTHEAST JAPAN
Mitsuo YAMANAKA, Kazuo SAITO and Kazuo IsHlzuKA
Mt. Hltk:L]acla Bbtanical Labomtoisl IShoku University and
Flicttlly ofGeneml Elarucation, lhmcrgata University
Synopsis
YAMANAKA, Mitsuo,' KazuoSAIT6" and Kazuo IsHIzuKA"" (Mt. Hakk6da Botanical Laboratory, Faculty of Science, T6hoku University' and Faculty of General Education, Yamagata University" ) Historical and ecological $tudies of Abies mariesii on Mt. Gassan, the Dewa Mountains, northeast Japan. Jap. J. Ecol. 23, 171-185 (1973) The subalpine vegetation in north Honshu shows a sharp contrast in physiognomy. Abies mariesi'i and 71izrga diversijblia ar'e well established in the inland subalpine region whiJe scarcely in the Japan Sea area. On Mt, Gassan in the Dewa mountains, Abies maiiesii occurs sporadi-
cally on a lava plateau situated on the leeward side of the mountain and screeneq from the strong westerlies or northwesterlies in winter, It was revealed by the pollen-analytical study aimed to elucidate the vegetation history of this mountain that the subalpine conifers had been mere extensive here under the Late Pleistocene climate but retreated under the more recent conditions of heavy snowiall and strong wind. The present occurrence of Abies is, therefore, thought to be a relict of the Late Pleistocene.
Further investigations were made on the floristic composition of the Abies habitat, the community structure, the dynamics of the Abies population, the growth form and the seil pro- file of its habitat. The physiognorny of the Abies community is, as a whole. that of the mixed thicket of Abies and deciduous broad-leaved chrubs, covering the wet alpine pod$ol on the ill-drained flats. The stems grow so high on the well-drained soil as to be ifljured or de- formed serieusly by the heavy snow cover and strong wind, so that they can hardly survive there. The wet alpine pedsol is probabiy of gtreat advantage to the Abies survival because of the stunted form that prevents suffering from the effect of snow and wind.
The subalpine vegetation in north Honshu is (Mt. Hayachine), while it is scarcely found on rnarkedly modified by the climatic condition in the mountains of the Japan Sea area(Mts.Iide, winter and provides a sharp contrast in physi- Asahi, Gassan, Chokai, Iwaki etc.). This is ognomy. The ciimate of the JaPan Sea area is also true in the central portion of the Ou characterized by the strong westerlies or Mountains (Mts. Akita-koma, Yakeishi, Kuri-
northwesterlies and heavy snowfall in winter, koma, Fupagata, etc.) that is not screened
whereas that of the inland area is moderate. from the westerlies by the higl) mount'ain of The subalpine coniferous forest of Abies the Japan Sea side. The subalpine region there mariesii and Il;trga diversijblia is well estab- is occupied mainiy by the deciduous broad-
lished both in the north and south of the Ou leaved scrub of (?tterczas mo?rgolica var. undtt- Mountains (Mts, Hakk6da, Hachimantai, Zao latijblin, Alnzas maximowic2ir; Acer tschonaskii
and Azuma) and in the Kitakami Mountains etc., the dwarf bamboo scrub of dma kurilensts
and the various types of snow-bed vegetation Received Oct. 16, 1973
171
NII-Electronic Library Service The EcologicalSocietyEcological Society of Japan
Vol. ea, No.4 H4 th re \A su, Aug., 1973
occur sporadicaily on some of these moun-
tains, viz,, Abies mariesii en Mts. Gassan and
Kurikoma, and 71ls;trga diversifolla on Mts. Iide, Iwaki and Yakeishi.
On the other hand, the recent poilen-analy- tical studies (HIBINo 1969 and 1970,YAMANAKA 1969) have revealed the more extensive
occurrence of Abies, 71strga, ICicea and Beimla
during the Late Pleistocene epoch even in the
Japan Sea area. These ieatures suggest that the current ciimate of the strong wind and heavy snowfall
in winter, together with the long duration of
snow cover until late spring or early sumrner, i exerts detrimental effects on the growth and
establishment of the subalpine copifers in the km Japan Sea area.
Mom is the first to have reported on (1969> Fig. 1. Map showing the situation of the repre- the present occurrence of Abies mariesii on sentative mountains in nomh Honshu Mt. Gassan although without phytosociological in winter 1). and ecological descriptions. Some efforts Japan (Fig. Topographically, Mt. Gassan appears to be (IsHIZUKA 1972, SAIT6 1972) were made prelimi･ a on all escarp'- narilytodescribe its ecological features. The shield volcano truneated sides by ments or steep slopes 2). main ridge present paper is concetned with the further investigations aimed to elucidate the vegeta- extends in a north-south directionat the of mourrtain. and tion history, especial;y the deterioration western part the On the east north sides, slopes of extend process of the subalpine conifers with special gentle lavaflows main ridge, until reference to the climatic change after the Late from the they are cut off by a Pleistocene on Mt.Gassan and to search for series of escarpments at altitudes between the cause and manner in which Abies mariesii 1500mand1300m Two flats called Midaga- survives here. hara and Tsukimigahara are formed at the The field work was done in the summers northern and eastern ends of the lava slopes. At the west, ridge of 1970 to 1972 with the kind help of the the main continues to the members of the Nature Conservation Society steep slopes descendingdownward to 1200 to 13oe rn. of the Dewa Mountains, to whom the writers The climate is characterized, as usual in the are greatly indebted. Cerdial thanks are due to moufitains near the Professor Jun NAKAMuRA of the･K6chi Universi- Japan Sea coast, by the snowfall and strong northwesterlies ty for his valuable advice on the polien-ana- heavy in 1ytical study. winter. Their combined effects results in the heavy accumulation of snow on the east or southeast slopes and escarpments. Area Studied Mt. Gassan is an extinct volcano located at The vegetation of Mt. Gassan was already almost the center of Yarnagata Prefecture and described by SuzuKi et al. (1956). The Fbgzcs rises to a･height of 1980m above Erea level, crenuta forest is well established as the cli- facing the northwest winds from the Sea of matic climax in the montane zone, and h,･ 172 NII-Electronic Library Service The EcologicalSocietyEcological Society of Japan Vol. as, No. 4 JAPANESE JOVRNAL OF ECOLOGY Aug., lg73 't4ilsua,g･ew )s '\ke'ng'a'nf}'h'd""'!'" edge of the escarpment and at the tops of the .?f XN low folds of lava-land-formation. a' IE,:SliL pt.i ;{!%t M The thick snow cover on the eastern slopes tsvangNz2%'$ )'!,{sr,;6{::;iig,.,..IIilEtsiW of the mountain remains until summer or ' z often until late autumn. It brings about the ± ･' X,K.,-, eeSfiKva %,lliiklpreponderance of the snow･bed vegetation in Sl ,.. zztue the plant cover. gewl\r).･The subalpine deciduous scrubs and the Eiasa zl tsB--es# ee'.i.li.i,,. . Ival' scrub are restricted to the ridges and the edge yZ. area of the fiats or slopes, where the duration XJ sk, /-llitflS:i.riuY'r.l'E.-･;'" =iptt[t of snow cover is relatively short. The habitat XNJi.t-,"･'r'trvrv-.r6,of Abibs mahesii in Fig. 2 is in the area of ･ as relatively ･ Xpt`--x",.Tsu.kemiga>llz..early snow melt. Abies martesii is here associated with the decidnous shrubs and Sczsa leurilensis. It is to be noted that this habitat is also protected agaist the strong affects of the northwesterlies /S in winter. other hand, moors of various types y/i//tes.x'"' On the lkand sizes are found in and around Mt. Gassan. eessximegss rmwag4$eg".\eqtm,# Arnong them, the Nembutsugahara moor is glQ most suitable for the po11en-analytical study Ng. 2, ssTopographic rnap of the nomh of Mt, part Gassan. Contours at intervals of 20m, since its peat deposit is thickest. It is develop- 'Ihe stippled area indicates the distrjbntion of ed on a granite plateau of the Cretaceous to Ables tnatiesii, and the line.A-B the site of the Early Tertiary age. It is located ca. 6km east transect belt of the smmit of the mountain and ca. 6.5km extends up to 120e to 14oom in altitude. southeast of the Abies habitat, at an altitude of There it reaclies the forest limit in a peculiar about llOOm. The volcanic ejecta repeatedly form of dwarfed, dense forest. The subalpine accumulated as to form thick impermeable zone is presumed to occupy the area from the horizons in the soil. forest lirnit to the altitude of 1700rn or so, The ridges and slopes surrounding the rnoor Fagtes forest and is mainly cevered by the subalpine broad- are covered by the c7ienate leaved scrub, the 5kzsa han'lensis scrub and the admixed with Pinus parvptom var. pantaptrylla. snow-bed vegetation. The alpine zone is the The flat around the moor is occupied by the area above 1700rn or so and is characterized scrubs dominated by Qnerctts mongolica by the ericaceous dwarf scrub. var. esnd"latt;foha associated with Alnzas The existent growths of Abibs mariasii are matsttmurae, ILex strgerold var. bem'pandun- plotted in Fig. 2 by the field ebservation and culala, HZz,namelis iciponica var. obtzcsala, the interpretation of air-photos. The main SmpPloeas chinensis f. Pt'losa, Eiorbtts commim, habitat lies in the area along the edge of the Pivnus g,eJuna, Magnolia salicijiolin, Fran'ntas flat or gentle slope in the Baramcnnizawa lanzrgi'nasu var. samala, Acer tscJronasldt region, between the two flats of Midagahara RkodOdendron brachyczirpum, Slezsa leurilensis and Tsukimigahara. On the flats, their dense and stunted trees of Fcrgzcs cienata. The growth is restricted to the two types ef existent vegetation of the moor is chiefly well-drained habitabs, a narrow zone along the cornposed of Mbliniotksis jopanim, Mrtrgmites 173 NII-Electronic Library Service The EcologicalSocietyEcological Society ofJapanof Japan Vol.23, No.,4 H ]P thme # k st.. Atrg., 1973 stMgsalt ,,seygSfo gps,fo st/ge<,,g,iteclge?LofLct' looot. gpeatysitt [li]sandys,it MII]siLtyaay Fig. 3, Main pollen diagram of the sediments from the Nembutsugahara moor. The frequencies are expressed as percentages of total arboreal pellen communis, En'ophonen vergznainm. L)csichiton The pollen frequencies were determined for camtschatense INlexrthecium aslatieum, Seversla every 10 cm intervals of the columnar sample. Penmpetala, Eiangbedsothcz tenuijiolin var. alha, A modified method of KOH-ZnCl2-aceto- J[lrase7zz rotundifolin, M2?qvanthes twfolinta, lysis(NAKAMuRA1967)was employed for the Lobelin sessilijblin and S¢)hcrgnu"z spp. preperation of the materiais, The result is shown in Figs. 3 and 4. Pollen-Analytical Study On the basis of the fluctuations of rnain A columnar sample of 190cm in length was pollen taxa in the diagram, the following five obtained frorn the center of the Nernbutsuga- forest stages are recognized in the vegeta- hara moor of by a hand borer Hillertype. The tional history: stratigraphic profile is as follows: e-60cm Peat containing silt, biack･ ' (1) Otterczas-Beinla-conifers stage to dark gray in color. <190-180cm in depth from the 60-100 cm Peat containing silt and fine surface) grained sand,･ black. <2) Lower Querczrs stage IOO-125cm Sandy siltcontaining angular (170-110cm in depth frorn the gravel$, white. surface) 125-145cm Silty clay, white. (3) ]Fkegzas stage (100cm in depth from 145-160 cm Sandy silt, white to light the surface) brown. (4) Upper Qtterczts stage (90-40cm in 160-180cm Sandy silt containing angular depth from the surface) gravels, white. (5) Anus"Fkegtcs-Qtterctes stage 180-190cm Siltyclay,gray. (30-O cm in depth from the surface) I74 NII-Electronic LibraryMbraryService Service The EcologicalSocietyEcological Society of Japan Vol. 23, No. 4 JAPANESE JOURNAL OF ECOLOGY Aug., 1973 CM to those Betula Z6ne of ermaniz a common species in the subalpine zone. The (}zterctts pollen ,of the first stage must, in all probability, have 2 been originated from Q. mongolica var. undulatijblin. This species is distributed in 40 the upper montane to subalpine zone in the Japan Sea area and is found in the Nembutsu-. 60 gahara area. As a consequence, it is safely said that the 80 subalpine forest eonsisting of Abtes (probably A. man'esii), 7lszrga (T diversijbliaL IIibea (ZR 1oo spp.), and Beimla as ermaniV extended to the Nembutsugahara area in the past. And it 120 seems that Qzterctts mongolica var. undulati- folia becarne abundant in this area at the 140 beginning of the moor-development, The first stage rnay possibly correspond to the Upper 160 Pleistocene, an age during' which the climate was colder and less snowy than at present. 180 There is a sharp increase of Ouerczas with a decrease of Betula and conifers at the begin- ning of the second stage, the lower Oztercus stage. This suggesbs that the scrub Fig, 4, Total pollen diagram of the sediments of Qz{erczcs from the Nembutsugahara moor. The frequen- mongolica var. crndulatir?)lia rapidly extended cies are expressed as percentages of total pollen. to the area around the moor, followed by the B:Boreal elernents, T:Temperate elements, retreat of the boreal N: Non arboreal pollen, S:Spores, Q: Querczas species, Consideredfrom the environmental conditions of the existent habitat of Qteercus mongoldea var. undulati- Such conifers as Abies, 7)inga and Picea are faha, it is assumecl that the heavy snowfall much more found in the first stage, the (?uerczts and the long duration of its cover were -Betula-conifers prevail- stage, and accompanied with ing during the second stage. Betula, Pinzts and Querczas. The Abies pollen In the third stage, the thgtts stage, thgus continues at the rate ef 1 to 1.5 per cent shows a sharp increase with the depression of toward the surface layer, YAMAGATA(1957) QteeMtes. This indicates that the cool tem- also detected the pollen from a thin deposit of perate forest of Fkegus crenate extended widely a moor near the summit of Mt. Gassan. It is to the Nembutsugahara area in this stage and certain that the Abies pollen of the sgrface that the climate was milder than the previous layer was derived from Abies man'esii growing stage. The Symplocas pollen shows a marked in the Baramomizawa region. From the fre- increase in this stage. The same feature was quence of the Abies pollen in the first stage it observed in the pollen diagram of the Ryugahara should be assumed that the of Abies in growth moor on Mt. Ch6kai (YAMANAKA 1969). The the Mt. Gassan area in that stage was more Scladopilys pollen is also found in this stage. extensive than at present, This is an endemic conifer of warm-temperate The morphological features of the fossil Japan and the current northern limit of its Betula pollen in the present study are similar native growth lies in Fukushima Prefecture. It 175 NII-Electronic Library Service The EcologicalSocietyEcological Society of Japan Vol. 23, Na 4 e Zi ts nt, \ k ge,. Aug., 1973 seems that the northern limit of that eruption whereas 'northward genus the layers above 100cm advanced further in the third consists of peat containing silt. Therefore, a stage. This stage should correspond to the time gap is recognized at the 100cm level period RII of NAKAMuRA(1952). between the thgtes stage and the upper There is a distinct unconformity at the 100 Qzeercms stage. It is clear that the peat above cm level･in the columnar section of the sedi- the 100cm level accurnulated on the imper- ment. The layers below 100 cm in depth from meable layer of volcanic ash. the surface･are cornposed of silt or silty clay The distribution pattern of the pollen taxa with some organic matter, and are assumed to in the fourth stage, the upper (?uerctes stage, is have orginated from the prdducts of volcanic similar to that of the second stage. This Tab]e l,FIQristiccomposition of the belt transeet laid on the names are those Quadratnumber 12345678910ll12 Distance(m) o-10m10-2em2e-30m30-40m4e-50m50-60m60-70m7D-80rn80H90m90-100m100-110m110-120m ' Exposure{degrees) N30WN20WN20WN20WN20WN25EN40WNIOWN5WNIOWN5WN5W Ine]inatioa Ilexsugerokivar., +121+12+1111 brevipeduncutata(I) Viburnumfurcatttm(Vi) 1+..+.l.+.'+ Sorbuscommixta(So) '+121'.++.-' Rhodedendron brachycarpum {Rb) 1+11 ++++. + +++ . Aeanthepanax sciadophylloides + + + Meneiesia multiflora + . Vteccinium ovalifelium . Magnolia salicifotia + Leucethoe grayana + + . . . var. eblongifolia Salix reinii +.. , Tripteygium regelii . - +. Tripetaieia bracteata 1 + . Tripetaleia paniculata Leucethoe gmyana . var. glaucina elethra barbinervis Rhododendren aibrechtii Cornus controversa , ' Alnus pendula . , (Herb layer} Abies mariesii {sap}ings) i+i + + + + + + + + 122 Number of speeies in the 34 25 29 28 28 25 26 30 28 20 15 herb layer l76 NII-Electronic Library Service TheTheEcological Ecological Society of Japan Vol, Z3, No, 4 JAPANESE JOURNAL OF ECOLOGY Aug., 1973 indicates･that Quercus mongolica var. undu- and then gradually increases toward the sur- iattfolin, which receded during the third stage, face. These facts indicate that PintLs parvij707u proceeded again in this stage and that the var. penmpdyUa, Fcrgms crenala and Alntts retreat of the Fagtcs creuata forest was mats"moriue etc. are gradually encroaching on induced by the ever-moisture of the ground. the Nembutsugahara area under the recent The marked increases of Ainzcs, Fcrgtcs and climate, which is rnore or less cooler than that Alnms are seen in the fifth stage, the Pinus- of the third stage. Fcrgtcs-Querctts stage. Qeeerct(s, a dominant' FIOristicCompositionof Abies member of the preceding stage, decreases to a Cemmunity minirrium of 8.5 per cent at the 30cm level, The pollen analysis provides an evidence Baramornizawa flat, Abbreviation$ in parenthesis at the end of species used in Figs, l3 14 15 I6 17 18 t9 20 21 22 23 24 25 26 27 28 29 30 31 120- 13e- 140- 150- 160- 170- l80- 190- 200- 210- 220- 23e- 240- 250- 260- 270- 28e- 290- 300- 130m 140m 150m 160m 170m 180m 220m 190m 200m 210m 230m 24om 2som 26em 27em 2som 2gom 3oem 31om N40E N35E N E20N N40E NIOE N30E NIOE N15E EION E40N EION E20N N20WN30E N45E E20N E20N E20N 15 10 IO 10 5 5 5 5 5 5 IO 20 15 5 5 15 25 30 30 3.0m 3.0m 3.0m 3,Om 3.0m 2.5m 2.5m 3,Om 1.5tn 1.5m 2.5m 3.5m 3.5m 3.5m 4.0m 3.5rn 3.5m 2. 5m 2.5m 232321324+ 2323' +223+ 2333 13231 +-2332 +2331 .3241 +313+ 32 43+3+ -+ 2421 2331 343+ ++21 233 1- .31 4･ .1 2. -- ++1+ 2+ 2 1+1+ 1 1 1++1 + + -+1 .14 .1 +t 1 + +++ ,1 +3 . .+ ++ + +++ . -- + . . . i- + . -- .+ + + . -- . + . + - . + . . - t . , . ･4 + ' -- .++r . . -l t . . , .. .. ,. . . + . . 1･･2 , 128 t22 +26 13e +32 +29 +33 +27 ,30 +25 125 .13 +18 +26 -427 29 20 22 13 177 NII-Electronic Library Service The Ecological Society of Japan Vol, as, Ne.4 Hpt th ma \k tw･ Aug., 1973 that the deterioration of the subalpine conifers mutica Clintonin ndensig (haliS gn)eithii, ete. frorn this mountain was induced by the clima- are peculiar to the well-drained condition, tie change since the Late Pleistocene and that while den2lesia multij7ova, Heloniopsis erien- 'talds, the present occurrence of Abies mariesii in the Coptis twfolin, daTex blophan'ca,)ba,etc. to Baramomizawa region is a relict of that age. the more wet grounds. Such hygrophilous It, however, remains unsolved why and how it plants as ltleratrum stamineerm, 7>rautvetteha survives under such a serious condition as Table Floristie prevailing here. 2. compesitlon'of Sts. 1to6 The physiognomy of the existent community of Abies is, as a whole, that of the mixed thicket of Abies mon'esii and broad-leaved shrubs. Abtes trees often show more or less contagious distribution with small clumps. In an attempt to e!ucidate the reiation of theoccurrenceand growth of Abies mariesii to the habitat conditions and to the competition with the shrubs, a transect belt of 310m in length was set in the thicket in roughly west-east direction, starting from the eastern margin of the snow-bedvegetation, and ending at the top of the escarpment (see Fig. 2). The dominance of each species was recorded by the Braun-Blanquet's scale in each of 10 × 10m quadrats. Table 1 shows the re- sults mainly for the shrub layer, Competing with Abies men'esii such shrubs as Qzeerctts mongolica var. undulatdr2)lta, Acer tschonosleii and SLLsa leztrilensis grow more or less abundantly in the shrub layer throughout the thicket. Abies man'esii becornes a domi- nant member at the top of a lava fold (110-120 m) and at the edge of the escarpment {250-270m). The doMinance ef Qtte,ctts and Acer is also closely related to the micro-relief of the ground, The flat of inclination less than 5' is covered by vigorous growths of Qt{erczcs. Acer tends to occupy the gentle slope of 5"-20" around the lava fold (9e-150 m) and the rivulet sides (230-25em). It is to be noted that the occurrence of Abies sapling is a]so common in these areas, The steep slope near the top of the escarpment is again dominated by QuerczLs, although it differs from its preceding stand in the undergrowing herbs, Among the undergrowths Polystichopsis 178 NII-Electronic Library Service The EcologicalSocietyEcological Society of Japan Vol, 23, No. 4' JAPANESE JOURNAL OF ECOLOGY Aug,, 1973 1'apandna, 7"ilingia hoiopetala, Hbmerocallds with Abies and suppresses the develeprnent of dumortlen' var. esculanta are conspicuous only the understories, while that of St. 2 se sparse- on the over-moistened ground, ly that the shrubs as Aceag ezteiztes, Rhodbden- dron, thsa etc. ,grow luxuriantly. The Abies Community Structure and Soil 1'.rofile populatien of these stands shows a sharp con- The above observation suggests that the trast in the size distribution pattern. The pat- micro-relief of the ground surface exerts some tern of St, 1 is two-stratified with two peaks influences upon the commupity structure and in the, canopy class and the seedling class, dynamics of the Abies population, presurnably while that of St. 2 shows a gradual decrease through the soil wateriness, In this connection, with increasirig height. The same relation is found a detailed investigatien was made at six between Sts. 3 and 4: St. 3 represents the stands (Sts. 1-6) selected in the area: Sts, 1 two-stratified distribut'ion of Abies by size and 2 were set on the tops of the lava folds, class although with somewhat low densiity of' Sts. 3 and 4 on the flat adjoining to the folds, the large trees, while St. 4 the L-shaped dis- and Sts. 5 and 6 on the flats apart from the tribution. The voluntary development of the above folds. The floristic composition of each shrub layer is found in both Sts. 3 and 4. Sts. 5 stand is shown in Table 2, and the vertical and 6 show the typical struct'ure of the structure of vegetation and the size distribu- deciduous broad-leaved scrub established on tion of Abies in Fig, 5. the moistened flat, The shrub layer differerrti- Sts. 1 and 2 are equally four layered and 4 ates into the upper and lower ones, and the m high. The differences between these two herb layer is well established with the hygrop- 'herbs stations are in the other features of structure. hilous and ferns. The uppermost layer of St.1 is densely grown The seil profile of each stand- is Shown in xN''''tt't-''''''tttttttt'ttttttttttt :.ii8'''''''tt'''''''''''''''''''''o40eo St. 5 ."`-gO,82o t5 st.6 6･.,O o 55 .1-:';1;.1ii/"::"tttt o 50 loo 5oo 20 St, 5 Q /tt'oo40 5 F: 300 20 eo t40 20 oo 50 too vvv vvvv 55 St. I l,s . :f, 40 20 O O20 40 60 80 30 20 10 O, O 20 40 60 80 coverage c%) Coverage t%) ,ko,'fig,L",dj//d,"P6S,., XO',O,f,t",d',",`d,"76S,.2 Fig. 5, Diagrarns showing the distribution of Abies population by size class and the vertical structure of vegetation at Sts. 1-6. [IiswAbies mariesii, Elthll Deciduous broad-leaved trees and shrubs, [X}l] Evergreen broadleaved shrubsl EZ2 SLzsa k"rilensis, M Herbs and ferms 179 NII-Electronic Library Service The EcologicalSocietyEcological Society of Japan A t ± Vol, 23, No, 4 HZS te F-t, 7 za pe, Aug., 1973 Depth (cm) LFHAI L: 5 =l==n.------LFAEA2 LFAIA2 o L-Fp--n A, ------=MkdtxxxRxxxKxxxxx'=xK to A2 A2 A Bl R B B 20 Br Bt R B2 50 R B2 B2 40 R 50 ' St.l . St.2 St,4 St.5 St.6 Fig. 6. I-6, Soli profiles of Sts. Arrow:the ground water level, R:rocks and boulders, V:volcanic ash, See the text for further explanation Fig. 6. Sts. 1 and 2 represent the prefiles of Growth Form of Abies the podsolic soil, Rather thick L, F and H layers are composed mainly of the fallen The effects of the strong wind and snow leaves of Querctcs and Abies, Beneath the H cover upon the Abtas growths may be, to a layer occurs a very thick Ai horizon which certain extent, known by examining its contains much organic matter of blackish growth forms. For this purpose, feur additio- ' bro'wn color. A2 horizon is referred to the nal stands (Sts. 7-10) were selected in the layer mottled with grayish brown clods and dense groves of Abies. St.7 was on the top of rusty streaks of ferric oxide and underlained a heap in a slope facing the north with an by the reddish brown B horizon. inclination of 20" or so, and Sts. 8, 9 and 10 were set along the"" belt transect described At Sts. 4 and 5, F layer is well developed in while H layer is almest absent. The horizons the preceding section: Sts. 8 and 9 were on the beneath F layer are water-logged. This is top of the lava fold at 110 to 120 m in the belt thought to be the wet podsol intermediate transect, and St. 10 was on the flat of impeded between the forest soil and peat. At St. 6 the drainage at 80 m, At each stand, was set a horizon of much organic matter is deep and rectangular plot of 5 m × 10-15 m in size, Detai- sub-divided into two layers : the upper layer is led bisect charts were drawn or analysed for the well-developed humus soil and the lower each plot. They are shown in Figs. 7 to 10 in the usual A horizon soil, This is most similar the order of sequence, to that of the snow-bed grassland. The water- As described already, the stunted trees of iness of the soil may be presumed to be due to Abies tend to form small but pure groves on the depth at which ground water seepages the more favorable habitats (Sts. 7 to 9), thus occur along the soil profiles;it gradually giving a clumped appearance of distribution, increases in the order of the stand: Sts. 1 and Their best growth is encountered on the slopes 2, Sts. 3 and 4, and Sts. 5 and. 6, This water- and at the edge of the escarpment. Of the four iness may be maintained throughout the stands, St. 7 shows the best growing trees, season growing by thawing water suppiied attaining 6m in height and 40cm in d, b. h. through the under-ground. The trees on the lava fold {Sts. 8 and 9) are 180 NII-ElectronicNII-ElecEronic Library Service The EcologicalSocietyEcological Society of Japan Vol. 23, No. 4 JAPANESEJOURNAL OFECOLOGY Aug.. 1973 iu)AO --uHuADmo At Ab Ss e At N th e $ B so .'" t- B l---tt"----'ttl Hm Ls -X s V st..it-J . l tte l' o 5 $ to ---i-t5m Fig. 7.Bisectchart of St. 7.Abbreviations vid, Table 1 ll t th th' Q Q So Sc) ss . Q ' vi t 'Hm o Ss o vi t Ss o IOm 'Ab Fig, 8, Bisectchart of St.8. Abbreviations vid, Table 1 181 NII-Electronic Library Service The EcologicalSocietyEcological Society of Japan Vol. 23. No. 4 H 4 th nt #" es,, Aug., 1973 ee.- At At bo -.ny' Hrn 'Hm.. .-. ss . Rb N 'NHmtkIF--x Vi b. Hm Se Ss ...'.HM,'....At .,i'x. s +4t t - ''-i---.e .. - - vi . ss ts O 5 t -XU)--･ l5 Fig. 9. Bisectchart of St, 9.Abbreviations vid. Table1 Fig. 10. Bisect chart of St,le. Abbreviations vid, Tablel more stunted, the largestmeasures 4.0m misof10 The bisect charts of Sts. 7 to 10 exhibit height and 21cm in d. b. h. Their grewth various types of deformed Abies tree, The extremely suppressed on the moistened flat cause of the deformation is multiple, but the St, 10, the largest enly m being 2.0 highand impeded drainage is likelyto be a prime cm thick. factor for the trees growing on the flats as 182 NII-Electronic Library Service The EcologicalSocietyEcological Society of Japan .1973 Vol. 23, No,4 JAPANESE JOURNAL OF ECOLOGY Aug., exemplified at Sts. 8-10. KASHIMuRA (1ee4) The frequency of 7lsaga pollen, although revealed in Mt. Hakk6da that a reduction in without its existent growth in this mountain, the upward growth of Abfas is characteristic show a rnaximurn in the deptbs and decreases of a flat around a moor and is induced by the toward the upper layer. 71snga diversdelin is occasional alternation of the stem shooting at extensively distributed at present en the the tip of the trees. The trees become dwarfed mountains of the Pacific and inland area and with flat crowns like an open urnbrella. As also sporadically in the Japan Sea area (Mts. shown in Fig. 9, the majority of the Abies tree Iwaki and Iide). The present growth of IVcea at St. 9 show this tYpe of deformation al- is not found in northeast Japan except for a though the top shoots grow longer. relict stand of Picea gtehni on the serpentine Another type of deformation is observed at region of Mt. Hayachine in the Kitakami Sts. 7 and 8. In Fig. 8, the trunks of Abies are Mountains. Its pollen- and rnacro-remains, bent at a height of2m or so in the direction of however, are frequent in the sediments depo- the slope exposure. The trunk of the tree at sited during the Upper Pleistocene of the the left extremity is bent zigzag by repeated Pacific area (SoHMA 1959, YAMANAKA 1965, deformation. On the slope there is a tree bent 1971). Moreover, a large amount of Picea at the base. In Fig. 7 the height of bending is 4 pollen was detected in the lower layers of the m or so abeve the ground sunface. This type Dake moor located in Mt. Iwaki (HiB!No 1969), of deformation may be related to the settling It is, therefore, most Iikely that the boreal and pressure by creep of the snow drift in Ricea species such as R gtehni, R 1'eeoensis winter {YosHrl 1949, TAKAHAsHI et al. 1970). It andler R i var. hondoensis were also distrib- seems most probable that the height of bend- uted in the Upper Pleistocene in the area. ing is often determined by the average height The pollen-analytical studies in Mt. Iwaki of the deciduous trees and shrubs admixed in (HIBINo 1969) and Mt, Ch6kai (YAMANAKA the stand. This suggests that the lower layer !969), both with the quasi-alpine zone, have of snow cover is fixed and prevented from also revealed that the growths of subalpine creep by the dense stems of the shrubs and conifers were more extensive in the Late trees in it. Effects of the strong northwester- Pleistocene than at present. It is most reason- lies in winter are also indicated in the flag-like able that the scanty'distribution of Abies wind forms illustrated in Fig. 7, in which the and Ilstrga in the quasi-alpine zone isthe relict branches are restricted to the leeward of the of the Late Pleistocene, during which time the trunks. climate was colder and less snowy than at present, Discussion The pollen diagtrams at the beginning of the The pol]en-analytical study shows that the iewer Oteerct{s stage indicates the decrease of ' subalpine conifers had grown more extensively Betula, Abies, 71guga and Ricea associated with in this rnountain during the Upper Pleistocene. a distinct increase of QtterctLs. The change Abies mariesii is, nowadays, restricted to the may be attributed to the increase of snowfall Baramomi-zawa region situatedon'the leeward and snow cover duration in this area. The of the mountain and screened from the wester- conifers are supposed to have retreated to the lies. The occurrence of its pollen in the upper leeward with sherter duration of snew, cover, layers of the moor deposits is surely derived and the thickets of Qzterczss mongolica var. from this habitat. Its frequency in the depths undulattlblin to have eccupied greater parts of may be explained by the more extensive dis- the subalpine zone, tribution in the past. The physiognorny of the-present habitat is, l83 NII-Electronic Library Service The EcologicalSocietyEcological Society of Japan ' Vol. 23, No.4 -lk th e.e, cr!ast,, Aug. 1973 ' as a whole, that of the mixed thicket･ of Abies from HokkaidO to the Chugoku District along and deciduous broad-leaved shrubs, and the the Japan Sea coast : the regions above the 'zone Abies trees growing high over the thicket are Fagtcs cre?zala forest are-almost occupied almost deformed or injured by the heavy by the Betula ermonii forest in southwest snowfall and strong wind in winter. On the Hokkaid6 (TATEwAKI et at.1958) and by the well-drained podsolic soil, stem･elongation is Taxzts cwsPidula var. nana scrubon Mt.Daisen promoted and often tesults in its damage so in southwest Honshu serious that it can hardly survive. The height ever, the horizontal distribution of vegetation in of the damage by the creep and settling snow the islands of the nerth Pacific Ocean shows a drift is closely related te the average one of similar counterpart ef the quasi-alpine zone the accornpanying deciduous ttees and shrubs, extending north of the Miyabe line situated at and it reaches 2 to 4 m above the ground sur- the Etorof Strait in the Kurile Islands face. Therefore, such effect of the snow cover (TATEwAKI1957 and 1958). It is, therefore, of and strong wind is likely one of the causes of utmost importance to search for a further, the Abies deterioration from the Japan Sea proper explanation of these phenomena from area. the historical and ecological viewpoints, On the other hand, the stunted umbrel- la-shaped trees of Abies is characteristic of References the irl-drained podsol, the wet alpine podsol assigned as Pwi by OHMAsA (1950>. The same ] ) HIBiNo, K, : Pollen analytical studies of moors 17, 197-2el feature was also observed on Mt. Hakk6da by inMt, Iwaki.Ecol.Rev. (1969) 2) and K.TAKAHAsH!r Pollen analytical KAsHIMvRA (1964). It is ascertained from the study on the natural forests of Cmptomeria study of growth' form that the trees of this form 1'aPonica in Akita Prefecture. Ann. Rep. are, to a certain extent, frorn suffer- prevented JIBP･CT(P) 1969, 108-110 {197e) ing the harrnful effects of snow and wind, 3 ) HoRiKAwA, Y.: General aspect of vegetation of Moreover, Abies seedlings and saplings are Mt. Daisen, EcoL Rev. 1, 181-187 (1935) 4) ISHIzuKA, K., TAcHIBANA H. and K SAn'6: found much more on the wet alpine podsol. It Vegetation of Mt, Ch6kai. Mt, Chakai and was also shown on Mt. HakkOda that the Tobishima Istand, 52-88, Scientific Researeh reproduction of Abies trees is rather probable Society of Yamagata Pref., Yamagata {1972) on this type of soil (SAiT61970). Abtes mariesii 5) : Abies mariesii en MtGassan, grows scantily also on Mt.Kurikoma(YosHIoKA Northeast Japan-Generai description and its formg. Ann. Rep. 1971, et al. 1966) and its habitat is similar to growth JIBP-CT (P) 59-67 (1972) that of Mt, Gassan:it grows in a small greve 6) KAsHiMuRA, T. : Ecological studies of the on the flat adjoining the slope covered by the Takadayachi moor in the Hakkbda Moun- deciduous scrub and on the wet alpine podsol, tains V. On the thicket of Abies mariesii in and around the meor of Takadayachi. Thus, it seems that the wet alpine podsol is, to Ecol. Rev, 16, 107-ll3 {1964) a cetain extent, of advantage to the Abies 7) MiyAwAKi, A. et al, : Pflanzensoziologische survival under such severe climate as heavy Studien ueber die Vegetation der Umgebung snowfall and strong westerlies in winter, von Echigo-Sanzan u. Okutadami. Scientific The subalpine conifers are, as above-men- Report of the Echigo-Sanzan, Okutadamj and tioned, scarcely found on the mountains of the its vicinity, Niigata and Fukushirna-Prefec- ture, 577152, Nature Conservation Society of Japan Sea area, including the Echigo and Japan, Tokyo {1968) Dewa Mountains, and on those of the central 8) MoRi, K. : The occurence of Abies mariesii of the Ou Mountains, The similar portion forest zone on Mt. Gassan, the Dewa Moun- are a]so encountered phenomena extensivelyl84 tains. J, Jap. Forestry Soc, 44, 320-323 (1962) NII-Electronic Library Service The EoologioalEcological SocietySooiety of Japan Vol ．23、 No ，4 JAPANESE JOURNAL OF ECOLOGY A ．，1973 g ）NAKAMuRA ， 工 ：A comparative study of 24） ： Pollen analytical studies of moo 給 Japanese pollen records ． Res ． Rep ． Kochi in the Iowlands in Iwate Prefecture． Eco1． Rev， ・ univ ．1（8），1 20 （1952 ） 17，273−278 （1971） ： Kafun Bunseki Pollen analysis 10） （ ） 25） YosHII， Y ．： Efrects of snow on trees at high − 1 232 Kokin−shoten Tokyo 1967 ， ， （ ） altitudε （II）． Deformation of woody p】ants by OHMAsA M ．： Studies on beech forest soils， − 11＞ ， snow pressure． EcoL Rev．12，79 83 （1949） − Forest so 萱正s of Japan 1，1 243（1950） ム 26 ） Yos 田 olくA ．K ，et al．： Flora and fauna of the 12） SAITo， K ．： Ecological approaches to the study Mt ． Kurikoma area ， Report of Scientlfic north ・ of forestdistributionin Mt ，Hakk6da ， Researches of the Mt ． Kurikoma area ，33−97， east with ．special reference to soil Japan， Nature Conservation Society of Japan， Tokyo − cond 重tion， Ecol． Rev．17，217 273 〔1970｝ （1966） 一 13 ） ： Abies 漉 麟 on Mt ． Gassan， − northeast Japan Vegetation structure and soi 工 ・ profile of 比s habitat． Ann． Rep， J工BP CT（P ） − 摘 要 1971， 68 73 （1972） 14 ） 田 DEI ： zones in no 貢 heast ・ S ， T ． The forest 山中 三 男 斎藤 員郎 ・石 塚和 雄 ； 月 山 の 7 オ モ リ ト Japan， J． Tohoku Branch Jap． Forestry Soc ． ド マ ツ 群 落 の 変遷 と 生 態 2 2 2−8 1952 （）， （ ） 東北 日 本 の 亜 高山帯植 生 は ，冬 季 の 豪 雪 と 偏 西 風 の 15） SoHMA ， K ．： On woody remains from a Pleis． 影 で 日 で は が tocene peaty lignite at Otai， Aomori Prefec． 響 ， 本海側 と内陸側 大 きな相 違 あ る ， 日 − ture． Eco1． Rev．15，67 70 （1959） 本海側 の 越後山 系 ，出羽 山 系 ，そ の 他 の 山岳 で は ，亜 SuzuKl T ， et α ’．： Vegetation of Mt ． Gassan， 16） ， 高山性 針葉樹林 は ，例 外的 な小 林 分 を 別 と し て ，ほ と Reports on the Scientif重c Researches of Mts． ん ど 立 し な い が に − 成 ，奥 羽 山 系 や北 上 山 系 は み うけ ら Gassan and Asahi 1955，144 199， Yamagata 一 れ る ．出 羽 山 系 の 月 山 に は 東 出 腹 の 部 溶岩 台地 に ア Prefectura10ffice， Yamagata （1956） オ モ リ ト ドマ ツ が 生 し て い る が 山塊 東 側 の 仏 ヶ 17）TAKAHAsHI ， K ， et aL ： Damage of Cりψ’o 〃 躍 万8 自 ， 念 砌 の の こ iaponi forestscaused by snow pressure in 原 湿 原 花粉 分析 結 果 ， れ は 寒冷 な 後期 洪積 世 以 snow area especially relation the heavy ， in to の い っ て て い っ の 後 ， 降雪 増 加 とあ ま 衰退 し た も の 遺 topographyJJap ． Soc． SnGw and Ice 32 （1） 存植生 で あ る こ と が 明 ら か に な っ た．そ し て ， こ の ア 18 ）TATEwAK 且， M ，： Geobotanical studies on the オ モ リ ト ド マ ツ 自生地 は 冬 の 季 節 風 や積 雪 の 影 響 が い Kurile Is】ands ， Acta Horti Gotoburgensis 21 ．’ 一 く ら か る に ． こ の っ （2），43−123 （1957） ・ 緩和 され 地 形 あ る 条件 卜に あ て r は 〜 の ア オ モ リ ト ド ？ ツ 19） ： Forest ecology of the is止ands of the 帯 高 さ 1 6m と 落 葉 低 木 の 混 ・ no 覚 h Pacific Ocean， Jour， Fac． Agr ． Hok 生 し た 鹸林 の 相観 を 呈 し て い るが，．溶 岩 流地形 の 凸部 − kaidδ Univ．5ユ｝，371 486 （1958） ’ の も っ と も排 水 良好 な場 所 で は ポ ド ソ ル 化 土 嚶 が 出現 20 ） et α ’．： TATEwAKI s iconography of ー’ し ， ア 才 モ リ ト ド ？ ツ の 生 長 も比 較 的 よ く，そ れ だ け the vegetation on the natural forest in Japan に 積雪 の 沈 ド，翻 行や 風 に よ る 損 傷樹形 が著 し い ． こ （IV ）． Geobotanical study on the Fagzts crenata に し ポ ド ソ ル forest in the district of its northern limit． れ 対 ， 平担 地 で は 高山湿性 が出 現 し，生 Hakodate FGrest O伍 ce ， Hakodate （1958） 長 は 劣 化 して 樹 形 は 背 の 低 い 傘型 を 示 す ． こ の よ う な 21 ） YAMAGATA 0 ．： Apalynological study of bogs 形 は の が ， 樹 比 較的風 雪 被害 を ま ぬ れ ， 更 新 も す こ ぶ る − on Mt ． Gassan． Eco1． Rev ． M ，269 272 （1957） 良 好 で あ る． も っ と も排 水 不 良 の 場所 で は ア オ モ リ ト ． 22）YAMANAKA ， M ．： Pollen profiles of recent マ ツ ーV ド の 吏新 は み ら れ ず， ミ ヤ ナ ラ 低 木林 と な っ て sediments from the Tashiro moor ， Hakk6da − い る ， こ の よ う に 風 と雪 の きび し い 気 候 的 条 件 の も Mountalns． Eco1． Rev．16 155 199 1965 ， （ ＞ ． ． と で は 高 山湿 性 ポ ド ソ ル は プ t，モ リ ト ド マ ソ の 生 に 23） ： Palynological studies of moors in 存 − Mt ． Ch δkai． Eco1． Rev ．17，203 208 （1969） 有利 に 作 用 し て い る も の と思 わ れ る ． 185 一 NII-ElectronicN 工 工 Eleotronio Library Service