北海道の植生垂直分布と極東ロシアの対応植生

Abstract

The phytogeographical relationships of major plant communities in vertical distribution of Hokkaido to those in horizontal distribution of the Russian Far East were discussed. Six major plant communities appear vertically in Hokkaido. Each of them has its own phytogeographically corresponding plant communities in horizontal dis-tribution of the Russian Far East. The Quercus mongolica―Tilia japonica―Acer mono forest corresponds to the Q. mongolica―Betula davurica forest. The Abies sachalinensis―Q. mongolica forest corresponds to the Pinus ko-raiensis―deciduous―broadleaves mixed forest. The Picea jezoensis―A. sachalinensis forest is similar to the P. je-zoensis―Abies nephrolrepis forest. These three communities in the Russian Far East appear in the area under the maritime climate. The Betula ermanii forest in Hokkaido corresponded phytogeographically to the B. ermanii forest on the Kamchatka Peninsula under the oceanic climate. The Pinus pumila thickets correspond to the Larix gmelinii―P. pumila forest in the area with the continental climate. The wind exposed dwarf shrubs corre-spond to the treeless heaths in the Kuriles with the extremely oceanic climate. Apparent vertical arrangement of the plant communities on the upper part of the mountains of Hokkaido was inconsistent with the horizontal ar-rangement of the Russian Far East that consists of, from the continental to the extremely oceanic climate, the L. gmelinii―P. pumila forest, the B. ermanii forest, and the treeless heath community. The important characteris-tics of the vertical distribution of Hokkaido are that it has different horizontal plant communities in the Russian Far East in a same vertical series. The vertical distribution of Hokkaido presents the invaluable exhibition as a standing natural history museum