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THYRA SOLEM 《Boreas: An International Journal of Quaternary Research》1986,15(2):101-115
Pollen analysis, 14 C datings and peat stratigraphy from blanket mires overlying two of the six drumlins in the Momyr area NW of the Trondheimsfjord in Sør-Trøndelag county are presented in order to trace the peat development and vegetational history. 14 C datings of the mineral soil/peat transition in 9 of the II profiles indicate that peat formation started about 7,800 years ago on the drumlin plateaux which at that time had a vegetation of scattered birch trees. From the plateaux the peat formation spread slowly down the slopes. Eventually, the mire surface bore a cover of pines which disappeared about 4,900 years ago, at the same time as peat formation commenced at the foot of the drumlins. This was probably a result of a change in the water table and onset of erosion in the already existing peat on the drumlin plateaux. During a period of about 1,000 years this new peat buried a dense birch vegetation existing at the lower part of the drumlins. Peat growth then spread upslope, and the drumlins' overall blanket of peat was completed well before the Subatlantic chronozone. 相似文献
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Age, origin, and palaeo-ecological evidence of blanket bogs in Nord-Trøndelag, Norway 总被引：2，自引：0，他引：2
Pollen diagrams, 14 C-datings, and peat stratigraphy are presented from 3 sites in the Forradal sub-oceanic area in Nord-Trøndelag, a moorland complex of flat and sloping fens and blanket bogs lying 400–500 m above sea-level, ca. 40 km E of the Trondheimsfjord. The vegetational and climatic history during the last 8500 years is described, together with a survey of present-day conditions. The origin of the blanket-bog areas is shown to agree generally, in both time and mode of genesis, with similar bog types in Scotland and N England. Dates are given for the expansion of both alder and spruce, the latter occurring more than 1000 years later than in SE Norway. The possible role of provenance formation and Roman Iron Age amelioration of the climate is discussed in this connection. The course of the alder pollen curve indicates a drier and probably colder type of climate at ca. 3000–2400 B.C. 相似文献
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THYRA SOLEM 《Boreas: An International Journal of Quaternary Research》1989,18(3):221-235
Stratigraphical studies, pollen analyses and radiocarbon dating of peat cores from two blanket mire areas, Mannen and Hestevollane, on the central mountain plateau of the hat-shaped island of Haramsøy in the Nordøyane archipelago indicate that blanket mire formation here dates back about 3,000 years and was primarily caused by human activity, namely regular burning to provide or improve grazing areas. Corresponding investigations of peat cores from two strandfiat sites on either side of the island demonstrate that a population existed on the strandfiat at least 6,800 years ago and gradually converted the original vegetation of the strandfiat into pastures and fields. The human influence increased further about 3,000 years ago when the activity was extended to the mountain plateau where grazing and regular burning, in addition to deteriorating climatic conditions, resulted in blanket mire formation. 相似文献
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