| 释义 |
palsa Geomorphol.|ˈpælsə|
[ad. Sw. palse, pals (pl. palsar), introduced as a techn. term (palse) by Fries & Bergström 1910, in Geol. Fören. i Stockholm Förhandl. XXXII. 195, from Finnish and Lappish palsa. The pl. palsen, sometimes found in Eng., reflects Ger. usage.]
A mound or ridge of peat covered with vegetation and containing a core of frozen peat or mineral soil in which are numerous ice lenses, occurring in subarctic regions (usu. in bogs).
1942Geogr. Rev. XXXII. 420 Peat knobs in swamps and bogs and hillocks in tundra, commonly called Palsen, are described from northern Europe and Siberia in an extensive foreign literature. Ibid. 421 The solid cores of ice show that the mounds are not due solely to upward movement of fine material, as in the case of most Palsen. 1954W. D. Thornbury Princ. Geomorphol. iv. 89 On surfaces covered by a good growth of tundra vegetation low, rounded mounds composed of fine materials are often found. They are called earth hummocks or palsen. 1973A. L. Washburn Periglacial Processes 152 The ice lenses generally distinguish palsas from pingos. 1973Nature 9 Nov. 64/1 In Finland palsas are only found north of the coniferous forest limit. |