Higher phytosociological syntaxa on Svalbard and their use in subdivision of the Arctic

Idealized distributions of phytosociological syntaxa are arranged along topographical gradients on siliceous and carbonaceous substrates in the northern arctic tundra zone of Svalbard. Two alliances (Luzulion arcuatae all. prov. and Papaverion dahliani Hoffm. 68 all. prov. em.) and three associations (Gymnomitrio corallioidis - Luzule-tum arcuatae ass. prov., Cetrario nivalis - Luzuletum arcuatae ass. prov. and Raco-mitrio lanuginosi — Luzuletum arcuatae ass. prov.) are proposed. Luzulion arcticae (Nordh. 36) Gjaerev. 56 and Polytrichion norvegici Gjierev. 49 described from Scandinavia are supposed to be important syntaxa on Svalbard. A subdivision of the Arctic into four zones, arctic polar desert zone, and northern, middle, and southern arctic tundra zones, is proposed. These zones and the transitional hemiarctic zone are defined and mapped in Europe and adjacent areas according to phytosociological criteria. They are also compared with alpine belts of Fennoscandia. The following zonal syntaxa are proposed for Europe and Greenland: Phyllodoco — Vaccinion in the hemiarctic zone, Loiseleurio — Diapension in the southern arctic tundra zone, Kobre-sio — Dryadion (Tetragono — Dryadetum) in the middle arctic tundra zone, Luzulion arcticae in the northern arctic tundra zone, and Papaverion dahliani in the arctic polar desert zone.