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

Japanese Saltmarsh (General)

Japanese saltmarshes are largely composed of halophytic (salt loving) taxa that are distributed throughout the northern hemisphere.  More restricted and endemic taxa include grasses such as Puccinellia kurilensis, P. nipponica and Zoysia sinica var. nipponica (Poaceae) and the succulent Suaeda japonica (Chenopodiaceae). On the lower shore, seagrass beds include the endemic Zostera caulescens (Zosteraceae).

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.

References

Hosokawa, T., Tagawa, H. & Chapman, V. J. 1977. Mangals of Micronesia, Taiwan, Japan, the Philippines and Oceania. In: Ecosystems of the World 1 - Wet Coastal Ecosystems. Ed. V. J. Chapman. Elsevier Scientific Publishing Company.

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.