sphagnum(redirected from Spagnum)
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peat moss,any species of the large and widely distributed genus Sphagnum, economically the most valuable mossmoss,
any species of the class Bryopsida, in which the liverworts are sometimes included. Mosses and liverworts together comprise the division Bryophyta, the first green land plants to develop in the process of evolution.
..... Click the link for more information. . Sphagnums, the principal constituent of peatpeat,
soil material consisting of partially decomposed organic matter, found mainly in swamps and bogs in various parts of the northern temperate zone but also in some semitropical and tropical regions.
..... Click the link for more information. , typically grow as a floating mat on freshwater bogsbog,
very old lake without inlet or outlet that becomes acid and is gradually overgrown with a characteristic vegetation (see swamp). Peat moss, or sphagnum, grows around the edge of the open water of a bog (peat is obtained from old bogs) and out on the surface.
..... Click the link for more information. . Their leaflike appendages have many large cells with circular openings that enable them to absorb liquids readily; hence they are commercially important as a soil structure enhancer (or component of potting soils), packing material, and absorbent dressings and for other uses. Sphagnum is classified in the division BryophytaBryophyta
, division of green land plants that includes the mosses (class Bryopsida), the liverworts (Marchantiopsida), and the hornworts (Anthocerotopsida). The liverworts and hornworts are generally inconspicuous plants; common liverworts include species of the genera
..... Click the link for more information. , class Bryopsida.
a genus of bog, or peat, mosses (Sphagnales). Of the 320 species, 42 are found in the USSR. The genus consists predominantly of mosses that grow in dense aggregates, forming large cushions or unbroken carpets on sphagnum bogs. The plants are less commonly found in rain forests. The soft, erect stem is 10–20 cm tall; the branches are arranged in clusters. Both the stem and the single-layer leaves contain a large number of dead water-bearing cells, whose pores readily absorb water. This accounts for the high moisture capacity of sphagnum mosses and promotes rapid development of upriver swamps in places where the mosses appear. The lower stems die off annually and form peat; the apical branches, however, continue to grow. Sphagnum mosses are distributed predominantly in the tundra and forest zones of the northern hemisphere; in the southern hemisphere they are found high in the mountains or, less commonly, in the plains of the temperate zone.