Schweger, Charles E.

20 items:

Macrofossil and pollen evidence for full-glacial steppe within an ecological mosaic along the Bluefish River, eastern Beringia Plant and insect macrofossil assemblages dating to the full-glacial (late Wisconsinan) are rare from eastern Beringia. Here we present an assemblage of fossil pollen, insect and plant macrofossils recovered from alluvium at the Bluefish Exposure, northern Yukon Territory. Nine AMS radiocarbon ages place these data between ca. 18,880–16,440 14C yr BP (22,313–19,597 cal. yr BP). These data indicate that xeric steppe, rich in bunchgrasses Poa and Elymus, Artemisia frigida and diverse forbs was interspersed within a mosaic of local vegetation types, including mid-rich fens, mesic graminoid meadows, steppe-tundra and herb-tundra. Macrofossils and minor pollen of tundra forbs suggest steppe-tundra plant associations within... Categories: Publication; Types: Citation; Tags: Paleo and Holocene
Macrofossil and pollen evidence for full-glacial steppe within an ecological mosaic along the Bluefish River, eastern Beringia Plant and insect macrofossil assemblages dating to the full-glacial (late Wisconsinan) are rare from eastern Beringia. Here we present an assemblage of fossil pollen, insect and plant macrofossils recovered from alluvium at the Bluefish Exposure, northern Yukon Territory. Nine AMS radiocarbon ages place these data between ca. 18,880–16,440 14C yr BP (22,313–19,597 cal. yr BP). These data indicate that xeric steppe, rich in bunchgrasses Poa and Elymus, Artemisia frigida and diverse forbs was interspersed within a mosaic of local vegetation types, including mid-rich fens, mesic graminoid meadows, steppe-tundra and herb-tundra. Macrofossils and minor pollen of tundra forbs suggest steppe-tundra plant associations within... Categories: Publication; Types: Citation; Tags: Paleo and Holocene
Vegetation buried under Dawson tephra (25,300 14C years BP) and locally diverse late Pleistocene paleoenvironments of Goldbottom Creek, Yukon, Canada Paleoecological research at Goldbottom Creek in the Klondike region of Yukon Territory (NW Canada) documents an in situ riparian grassy meadow that was buried during the winter or early spring by Dawson tephra, near the onset of Marine Isotope Stage (MIS) 2, ca. 25,300 14C years BP. Analyses of vascular plant macrofossils, bryophytes, pollen, insects and paleosols from the riparian meadow contrast with evidence for well-drained, upland steppe–tundra habitats obtained from fossil arctic ground squirrel middens within the same valley. The mesic valley bottom vegetation consisted of grasses (Deschampsia caespitosa, Alopecurus), sedges (Carex), horsetail (Equisetum cf. palustre), diverse bryophytes and few forbs. Upland... Categories: Data, Publication; Types: Citation, Downloadable, Map Service, OGC WFS Layer, OGC WMS Layer, Shapefile; Tags: Paleo and Holocene
Tephrochronology, magnetostratigraphy and mammalian faunas of Middle and Early Pleistocene sediments at two sites on the Old Crow River, northern Yukon Territory, Canada Categories: Publication; Types: Citation; Tags: R1-Vulnerability Forest Species and Communities to Climate Change
Vegetation buried under Dawson tephra (25,300 14C years BP) and locally diverse late Pleistocene paleoenvironments of Goldbottom Creek, Yukon, Canada Paleoecological research at Goldbottom Creek in the Klondike region of Yukon Territory (NW Canada) documents an in situ riparian grassy meadow that was buried during the winter or early spring by Dawson tephra, near the onset of Marine Isotope Stage (MIS) 2, ca. 25,300 14C years BP. Analyses of vascular plant macrofossils, bryophytes, pollen, insects and paleosols from the riparian meadow contrast with evidence for well-drained, upland steppe–tundra habitats obtained from fossil arctic ground squirrel middens within the same valley. The mesic valley bottom vegetation consisted of grasses (Deschampsia caespitosa, Alopecurus), sedges (Carex), horsetail (Equisetum cf. palustre), diverse bryophytes and few forbs. Upland... Categories: Publication; Types: Citation; Tags: Paleo and Holocene

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