Included here is Honshu, Kyushu, Hokkaido, and the smaller islands of Gotto-retto, Tanega, Tsushima and Yaku.

Japanese Coastal Sand Dunes (General)

In sand dunes the principal mobile dune species are Carex kobomugi, Elymus mollis and Wedelia prostrata.  Mobile dune endemics possibly include Linaria japonica (Scrophulariaceae). In the semi-stable zones, Hibiscus hamabo, Rosa wichuraiana and Vitex rotundifolia often form low thickets. Mosses largely dominate the so-called grey dunes but lichens are largely absent. Dune woodland is well represented. The succession of ligneous vegetation on fixed dunes is thought to start with the development of Juniper conferta stands. This gives way the Pinus densiflora dominated vegetation, but is eventually succeeded by the endemic Tilia japonica (Tiliaceae) and various oaks. Smaller endemic dune trees occurring in southern areas include Eurya japonica (Theaceae) and Fatsia japonica (Araliaceae).  Unfortunately most of the natural dune slacks in this zone have been used for the cultivation of rice.

Hokkaido Coastal Sand Dunes

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).

Kyushu Coastal Sand Dunes

The following dune zones have been described for Kyushu coastal sand dunes.

Strandline
High tide mark ecosystems are well developed supporting both annual and perennial species. The main annual species is Salsola komarovii but Atriplex gmelinii is locally common. Perennial species typically include Calystegia soldanella, Glehnia littoralis (Apiaceae), Lathyrus japonicus, Linaria japonica and Xeris repens (Asteraceae).

Embryonic Dunes
Early dune formation is often evident in the more stable areas where they typically form a low foredune ridge up to 2 m high.  The main sand binding species here seems to be almost exclusively Carex kobomugi.

Foredunes
The main foredune ridge is relatively low with Carex kobomugi again being the main sand binder. However, this species is only capable of fixing a small proportion of wind blow sand and so the resulting fordunes are relatively small. Associated species are the same as those found in the strandline.

Sheltered slopes of foredunes and the zone immediately behind
Here a distinct community can often be found mainly consisting of Carex breviculmis, Ischaemum anthephoroides (a large perennial grass) and Wedelia prostrata.

Fixed dune grassland
These do not appear to develop in this part of the world which may relate to the fact that much of the dune sand is of volcanic orgin.

Blowouts and other areas of bare sand
These are not common but where they do exist the characteristic species usually include the sedges Bulbostylis barbata and Fimbristylis sericea, and the mosses Polytrichum spp and Rhacomitrium canescens.

Dune Scrub
In sheltered hind dune areas dense shrubs may occur. The main species are Elaeagnus umbellata and Rosa wichuraiana. Other species typically include the small herb Viola mandshurica.

 

References

Doing, H. 1981. A comparative scheme of dry coastal sand dune habitat, with examples from the eastern United States and some other temperate regions. Veroff. Geobot. Inst. Rubel, 77: 41-72.

Kanai, H. 1963.  Phytogeographical observations on the Japano-Himalayan Elements. Journal of the Faculty of Science, University of Tokyo, Sect 3. Bot. 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.

Ohwi, J. 1965. Flora of Japan. Smithsonian Institution. Washington D.C.

Satoo, T. 1983. Temperate broad-leaved evergreen forests of Japan. In: Ecosystems of the World 10 - Temperate Broad-Leaved Evergreen Forests. Elsevier.