Sakhalin-Hokkaido Conifer Forest
These forests are mainly confined to the montane areas in the south but further north go down to sea level. The three main trees include the endemic Abies sachalinense and Picea jezoensis, the near endemic Picea gledhnii (Pinaceae), but these may be intermixed with Betula ermanii and B. maximowicziana. The shrub layer may include Acer ukurunduense, Euonymus macropteris, Vaccinium smallii and the endemic Ribes sachalinense (Grossulariaceae), while the herb layer species include Cornus canadensis, Tiarella polyphylla, Maianthemum bifolium, Streptopus streptpoides, Trillium tschonoskii, and ferns and fern allies such as Rumohra mutica and Lycopodium serratum var. thunbergii. In certain dry habitats such as on volcanic soil, rocky or gravel ridges and slopes, or in the serpentine areas, as well as in certain wet habitats such as fens, swamps or marshes, Picea gledhnii usually forms the main tree species. In the sparse early stages of P. gledhnii forest on serpentine habitats the associated species characteristically include Berberis amurensis and the endemic Crepis gymnopus (Asteraceae), while the later stages often have dense undergrowth of the near endemic broad-leaved bamboo Sasa kurilensis (Poaceae). On the rock or gravel slopes, the forest floor is usually dominated by Menziesia pentandra, Rhododendron brachycarpum (R. fauriei) or the endemic Carex sachalinensis (Cyperaceae). Wetland P. gledhnii forests are also have varied composition, but species such as Carex middendorfii, Lysichiton camtschatense, Moliniopsis japanica or Osmunda asiatica may dominate the forest floor.
Sakhalin-Hokkaido Volcanic Vegetation
Because new surfaces are constantly being created on active volcanoes, they are very important to plant ecology especially in the study of plant succession. In this BioProvince ecological studies have been carried out on volcanoes such as Komagatake, Kousu and Ousu in Hokkaido. Some 20 years after volcanic activity on Ousu, a tall herb community including Ixeria japonica, Miscanthes sinensis, Oenotherea biennis, and the endemic Aster glehni (Asteraceae) had developed in the unstable accumulations of ash, soil and debris, whereas in the more stable areas a pioneer forest of Betula platyphylla var. japonica, B. ermanii, Populus maximowiczia and the endemic Salix sachalinensis (Salicaceae) had become established.
Sakhalin-Hokkaido Fens and Bogs
On Hokkaido’s Kushiro and Sarabetsu moors, two types of reed (Phragmites communis) fen have been identified. One is co-dominated by Carex miyabei and in the other by the endemic Carex augustinowiczii (Cyperaceae). The latter forms extensive tussocks often inhabited by Adenophora triphylla var. tetraphylla, Artemisia vulgaris var. kamtschatica and the fern Thelypteris palustris, while Calamagrostis langsdorffii, Hosta rectifolia, Sanguisorba tenuifolia var. alba, and the near endemic Solidago virgo-aurea var. yezoensis (Asteraceae) occur between the tussocks. With increasing development of acid peat, the near endemic grass Moliniopsis japonica (Poaceae) becomes the dominant species. This species has similar ecological requirements to Europe’s Molinia caerulea. Associated species include Eleocharis japonica, Pogonia japonica and the fern Osmunda cinnamomea.
Sakhalin-Hokkaido Alpine Grasslands
In the snow bed grasslands a number of communities have been described including ones co-dominated by the Phyllodoce aleutica and the endemic Salix yezoalpina (Salicaceae), while on Mount Rishiri these grasslands are occasionally dominated by the endemic Papaver fauriei (Papaveraceae). Other Rishiri endemics include Cortusa matthiola var. congesta (Primulaceae), Oxytropis rishiriensis (Fabaceae) and Trollius pulcher (Ranunculaceae). The so-called windward grasslands are mainly free of snow due to exposure to strong winds, which also have a desiccating effect. These areas are typically characterized by an abundance of leguminous species especially of the genus Oxytropis (Fabaceae), and regional speciation of this genus is a feature of the BioProvince. Some of the regional dominants include the endemic O. shokanbetsuensis on Mount Shokanbetsu, the endemic O. kodoana on Mount Hidaka and the endemic O. magalantha on Rubun Island. Other characteristic species of these grasslands include Bupleurum triradiatum, Minuartia arctica, Patrina sibirica, and the endemic Saxifraga nishidae (Saxifagaceae).
Sakhalin-Hokkaido Alpine Deserts
At high altitudes in volcanic areas, repeated accumulation of volcanic ejecta, short growing seasons and long lasting snowdrifts have created expanses of open vegetation. Two of the most characteristic species of these barren volcanic regions are Dicentra peregrina and Viola crassa. In the serpentinitic areas, these alpine deserts are characterized by high levels of endemism. For example, on Mount Apoi (Hokkaido) endemic species such as Cirsium apoiense, Erigeron thunbergii var. angustifolius, Hypochoeris crepidioides, Saussurea reideri var. yezoensis (Asteraceae), Primula hidakana (Primulaceae), Bupleurum nipponicum var. yezoense (Apiaceae), Viola hidakana (Violaceae), Hypericum samaniense (Hypericaceae), Aruncus dioicus var. subrotundus (Rosaceae), Callianthemum miyabeanum (Ranunculaceae), Arenaria katoana var. lanceolata (Caryophyllaceae), Betula apoiensis (Betaceae), Tofieldia coccinea var. kondoi (Tofieldiaceae), Allium schoenoprasum var. yezomonticola (family) occur, while on Mount Yubari (Hokkaido) the endemics include Lagotis glauca var. takedana (Plantaginaceae), Primula yuparensis (Primulaceae) and Viola yupariana (Violaceae). The dominant species in these serpentinitic alpine deserts include the endemic Arenaria katoana var. lanceolata (Caryophyllaceae) on Mount Apoi,the endemic Viola yupariana (Violaceae) at the centre on snow patches on Mount Yubari, and the endemic Saussurea chionophyllum (Asteraceae) forms the dominant species of associations found on Mount Apoi, Mount Tottabetsu and Mount Yubari.
Sakhalin-Hokkaido Vegetation of Coastal Cliffs and Scree
The sea cliffs of northern and western Hokkaido are known for their abundance of alpine and boreal species at low altitudes. These include Cochlearia oblongifolia, Dianthus superbus, Juniperus chinensis var. sargentii, Sedum ishidae, Trifolium lupinaster, the near endemic Draba borealis (Brassicaceae) and the endemic Primula modesta var. matsumurae (Primulaceae). At the foot of these cliffs, maritime screes occur supporting species such as Lathyrus maritimus and Lotus corniculatus var. japonicus in the less stabile areas, but with increasing stability these give way to a tall-herb community with species like Artemisia montana, Filipendula kamtschatica, Urtica platyphylla, Cacalia hastata var. orientalis, together with endemics such as Petasites japonicus var. giganteus (Asteraceae) and Polygonum sachalinensis (Polygonaceae).
Sakhalin-Hokkaido Saltmarsh
Like many northern saltmarshes, Salicornia europaea (aggregate) forms the main pioneer taxon, but here a belt of Spergularia marina landward of the pioneer zone also characterizes these marshes. Further inland the common species include Glaux maritima var. obtusifolia, Triglochin maritima and Potentilla egedeii var. groenlandica, while in the sub-arctic saltmarshes of eastern Hokkaido the endemic or near endemic Carex ramenskii, C. subspathacea (Cyperaceae) and Puccinellia kurilensis (Poaceae) occur.
Sakhalin-Hokkaido Sand Dune Vegetation
As with dunes throughout Japan, the mobile areas are dominate by Carex kobomugi, Elymus mollis, Glechnia littoralis, Ischaemum anthephoroides, Ixeris repens, Lathyrus maritimus and Zoysia macrostachys, but in addition, the norther mobile dunes of Hokkaido are characterized by Carex macrocephala and the near endemic Linaria japanica (Scrophulariaceae). Fixed dunes typically include scrub often dominated by Rosa rugosa, while interspersed among the scrub and occasional grassland are various flowering plants such as Lilium maculatum var. dauricum, Thermopsis lupinoides and the endemic Hemerocallis yezoensis (Hemerocallidaceae). Quercus dentata is usually the main tree species found on fixed dunes, but may be associated with a sparse covering of other trees including the endemic Salix bakko (Salicaceae).
Further information required.
References
Kanai, H. 1963. Phytogeographical observations on the Japano-Himalayan Elements. Journal of the Faculty of Science, University of Tokyo, Sect 3. Botany, 8: 305-339.
Kolbek, J., Srutek, M. & Box, E. O. 2003. Forest Vegetation in Northeast Asia. Kluwer Academic Publishers.
Numata, M. (ed). 1974. The flora and vegetation of Japan. Elsevier Scientific Publishing Company.
Numata, M., Miyawaki, A. & Itow D. 1972. Natural and semi-natural vegetation in Japan. Blumea, 20: 435-481.
Satoo, T. 1983. Temperate broad-leaved evergreen forests of Japan. In: Ecosystems of the World 10 - Temperate Broad-Leaved Evergreen Forests. Elsevier.