A 14,000-Year Pollen Record from Sithylemenkat Lake, North-Central Alaska

1990 ◽  
Vol 33 (3) ◽  
pp. 400-404 ◽  
Author(s):  
Patricia M. Anderson ◽  
Richard E. Reanier ◽  
Linda B. Brubaker
Keyword(s):  
Boreal Forest ◽  
Sediment Core ◽  
Pollen Analysis ◽  
Picea Glauca ◽  
Pollen Record ◽  
North Central ◽  
The Holocene ◽  
Unusual Combination ◽  
Shrub Tundra ◽  
History Of

AbstractPollen analysis of a 14,000-yr-old sediment core from Sithylemenkat Lake provides the first Holocene vegetational history for the Kanuti Flats of north-central Alaska. Basal samples contain a curious and unusual combination of tundra and boreal taxa. Pollen assemblages dating from 13,500 to 9000 yr B.P. are more typical of southern Brooks Range sites and indicate the presence ofBetulashrub tundra with increasedPopulusca. 10,000 to 9000 yr B.P.Picea glaucaappeared ca. 9000 yr B.P. andAlnusca. 8000 yr B.P.P. glaucapopulations declined between 7800 and 5000 yr B.P. with a subsequent reforestation byP. marianaandP. glauca. This pattern is seen at other sites in northeastern Alaska and suggests that the Holocene history of boreal forest is more complex than thought previously.

scholarly journals Disturbances Of The Holocene Lake-Bog Sediment Succession As Revealed By Pollen Record From Wietrzychowice (Southeastern Kujawy, Central Poland)

2015 ◽  
Vol 32 (2) ◽  
pp. 91-97
Author(s):  
Eva Břízová ◽  
Małgorzata Roman
Keyword(s):  
Middle Ages ◽  
Pollen Analysis ◽  
Pollen Record ◽  
Sediment Characteristics ◽  
Pollen Data ◽  
The Holocene ◽  
The Third ◽  
Late Middle Ages ◽  
Organic Sediments ◽  
Funnel Beaker Culture

Abstract Results of geological and pollen investigations of the lake-bog sediments from the section Wietrzychowice W5, located nearby the Neolithic Funnel Beaker Culture (FBC) megaliths, are presented. The pollen data reveal that sedimentation at Wietrzychowice has begun at the beginning of the Holocene (Preboreal). Pollen analysis was used to determine stratigraphy with regard to sediment characteristics. The pollen spectrum was divided into 8 LPAZes (1-7Xa, 7Xb) which were also, where possible, stratigraphically classified. Radiocarbon dating of 6 730 ± 90 BP (5 730–5 480 BC, MKL-702) at depth of 1.20 m confirmed the pollen analysis age estimation. Five settlement episodes were found in organic sediments in the upper part of the W5 core. The first was presumably during the Preboreal, the second in the early Atlantic, the third in the late Atlantic (probably Neolithic FBC), the fourth in the early Middle Ages and the last one in the late Middle Ages. The pollen analysis was useful to point irregularities in sediment succession. Such a situation made palaeoenvironmental interpretation difficult, but further research is still needed to enable an accurate reconstruction.

Penguin occupation in the Vestfold Hills

2008 ◽  
Vol 21 (2) ◽  
pp. 131-134 ◽  
Author(s):  
Tao Huang ◽  
Liguang Sun ◽  
Yuhong Wang ◽  
Renbin Zhu
Keyword(s):  
Sediment Core ◽  
Environmental Changes ◽  
Sediment Cores ◽  
East Antarctica ◽  
Before Present ◽  
The Holocene ◽  
History Of ◽  
Vestfold Hills ◽  
Free Area ◽  
Ornithogenic Sediment

AbstractDuring CHINARE-22 (December 2005–March 2006), we investigated six penguin colonies in the Vestfold Hills, East Antarctica, and collected several penguin ornithogenic sediment cores, samples of fresh guano and modern penguin bone and feather. We selected seven penguin bones and feathers and six sediments from the longest sediment core and performed AMS14C dating. The results indicate that penguins occupied the Vestfold Hills as early as 8500 calibrated years before present (cal. yrbp), following local deglaciation and the formation of the ice free area. This is the first report on the Holocene history of penguins in the Vestfold Hills. As in other areas of Antarctica, penguins occupied this area as soon as local ice retreated and the ice free area formed, and they are very sensitive to climatic and environmental changes. This work provides the foundation for understanding the history of penguins occupation in Vestfold Hills, East Antarctica.

Modern Pollen Assemblages and Vegetational History of the Moraines of the Klutlan Glacier and Its Surroundings, Yukon Territory, Canada

1980 ◽  
Vol 14 (1) ◽  
pp. 101-129 ◽  
Author(s):  
H. J. B. Birks
Keyword(s):  
Picea Glauca ◽  
Yukon Territory ◽  
Canonical Variate ◽  
Pollen Diagram ◽  
Modern Pollen ◽  
Canonical Variates ◽  
Shrub Tundra ◽  
History Of ◽  
Shepherdia Canadensis ◽  
Modern Pollen Assemblages

AbstractModern pollen assemblages have been studied from surficial lake muds and moss polsters collected from five vegetated ice-cored moraines of the Klutlan Glacier. The youngest vegetated moraine (K-II) is characterized by high pollen values for Salix and Hedysarum, K-III by high Salix and Shepherdia canadensis and low Hedysarum and Picea, K-IV by high Betula, Salix, and Shepherdia, and K-V and the Harris Creek moraine (HCM) by high Picea. Variations are summarized by canonical variates analysis. A percentage pollen diagram from Gull Lake on the upland east of the glacier records vegetational development since the deposition of the White River volcanic ash 1220 14C yr ago. An initial species-rich treeless vegetation was replaced by birch-alder-willow shrub-tundra, and this by open Picea glauca forest similar to present vegetation around the lake. Sites on HCM show two basic stratigraphies. Triangle Lake reflects vegetational succession from Salix-Shepherdia canadensis scrub similar to that on K-III today, through open Picea woodland of K-IV type, to closed Picea forests of K-V and HCM. Heart Lake and Cotton Pond reflect vegetational development following melting of ice underlying the spruce forests of HCM. These two types are summarized by positioning the fossil spectra on the first two canonical variate axes of the modern surface spectra.

CONTRIBUTIONS TO THE HOLOCENE PALEOECOLOGY OF WESTCENTRAL CANADA: I. THE RIDING MOUNTAIN AREA

1964 ◽  
Vol 42 (2) ◽  
pp. 181-196 ◽  
Author(s):  
J. C. Ritchie
Keyword(s):  
Boreal Forest ◽  
Lake Sediment ◽  
Pollen Analysis ◽  
Deciduous Forests ◽  
Pollen Spectrum ◽  
Spruce Forest ◽  
Mountain Area ◽  
The Holocene ◽  
Carbon 14 ◽  
Spruce Wood

The results of pollen analysis of three sections of lake sediment, sampled in the Riding Mountain area of Manitoba, suggest a tentative division of each into four zones. The lower, interpreted as representing a closed white spruce forest, is followed by an apparently treeless episode tentatively interpreted as a grassland phase; this is followed by a zone which suggests indirectly the prevalence of deciduous forests, possibly dominated by poplar, birch, and oak. The development of the mixed boreal forest, which prevails today, is marked by a rise in the spruce and alder curves. The suggestion that the sections are post-Valders in age is corroborated to some extent by a carbon-14 age measurement of 9570 years from a sample of spruce wood excavated from the bottom of a filled-in kettle in the vicinity; associated gyttja yielded a pollen spectrum very similar to the I zones of the diagrams.

scholarly journals The Holocene history of the southwestern Baltic Sea as reflected in a sediment core from the Bornholm Basin

Boreas ◽  
2000 ◽  
Vol 29 (3) ◽  
pp. 233-250 ◽  
Author(s):  
ELINOR ANDRÉN ◽  
THOMAS ANDRÉN ◽  
GUSTAV SOHLENIUS
Keyword(s):  
Baltic Sea ◽  
Sediment Core ◽  
Bornholm Basin ◽  
The Holocene ◽  
History Of

Postglacial vegetation history of the Mariana Lake region, Alberta

1994 ◽  
Vol 31 (2) ◽  
pp. 418-425 ◽  
Author(s):  
M. J. Hutton ◽  
G. M. MacDonald ◽  
R. J. Mott
Keyword(s):  
Picea Mariana ◽  
Picea Glauca ◽  
Vegetation History ◽  
Fossil Pollen ◽  
Pollen Record ◽  
Sparse Vegetation ◽  
Lake Region ◽  
History Of

A fossil pollen record extending from 11 300 BP to the present was recovered from Mariana Lake, Alberta (55°57′N, 112°01′W). Initially, the region had a sparse vegetation dominated by forbs and graminoids, which at approximately 10 500 BP succeeded to Picea glauca forest. Picea mariana – Sphagnum peatlands began to develop between 10 000 and 9500 BP. After 9000 BP Sphagnum-dominated sites decreased; P. glauca declined while Betula increased. From 7500 to 5500 BP Populus reached its maximum Holocene representation in the vegetation. Sphagnum-dominated peatlands almost disappeared. The changes following 9000 BP were likely caused by increased aridity. However, the presence of P. mariana, Abies, and Larix in the pollen record suggests that mesic sites remained. Beginning at 6500–6000 BP the extent of Sphagnum peatlands began to increase. Abies declined in importance following 5000 BP, possibly due to paludification of mesic sites. The expansion of parkland into central Alberta during the mid-Holocene did not extend to Mariana Lake. However, Mariana Lake records changes in vegetation resulting from increased aridity in the early to mid-Holocene which are not apparent at more northerly sites in Alberta.

No significant ice-sheet expansion beyond present ice margins during the past 4500 yr at Rauer Group, East Antarctica

2010 ◽  
Vol 74 (1) ◽  
pp. 23-25 ◽  
Author(s):  
Sonja Berg ◽  
Bernd Wagner ◽  
Duanne A. White ◽  
Martin Melles
Keyword(s):  
Sediment Core ◽  
Radiocarbon Dating ◽  
Ice Sheet ◽  
East Antarctica ◽  
Antarctic Ice Sheet ◽  
The Holocene ◽  
The Core ◽  
The Past ◽  
Field Evidence ◽  
History Of

AbstractThe history of glacial advances and retreats of the East Antarctic ice sheet during the Holocene is not well-known, due to limited field evidence in both the marine and terrestrial realm. A 257-cm-long sediment core was recovered from a marine inlet in the Rauer Group, East Antarctica, 1.8 km in front of the present ice-sheet margin. Radiocarbon dating and lithological characteristics reveal that the core comprises a complete marine record since 4500 yr. A significant ice-sheet expansion beyond present ice margins therefore did not occur during this period.

Stability of Holocene Climate Regimes in the Yellowstone Region

1995 ◽  
Vol 43 (3) ◽  
pp. 433-436 ◽  
Author(s):  
Cathy Whitlock ◽  
Patrick J. Bartlein ◽  
Kelli J. Van Norman
Keyword(s):  
Early Holocene ◽  
Summer Drought ◽  
Pollen Record ◽  
Holocene Climate ◽  
Pressure System ◽  
Climate History ◽  
The Holocene ◽  
Mountainous Regions ◽  
History Of ◽  
Wet Climate

AbstractA 12,500-yr pollen record from Loon Lake, Wyoming provides information on the climate history of the southwestern margin of Yellowstone National Park. The environmental reconstruction was used to evaluate hypotheses that address spatial variations in the Holocene climate of mountainous regions. Loon Lake lies within the summer-dry/winter-wet climate regime. An increase in xerophytic pollen taxa suggests drier-than-present conditions between ca. 9500 and 5500 14C yr B.P. This response is consistent with the hypothesis that increased summer radiation and the expansion of the east Pacific subtropical high-pressure system in the early Holocene intensified summer drought at locations within the summer-dry/winter-wet regime. This climate history contrasts with that of nearby sites in the summer-wet/winter-dry region, which were under the influence of stronger summer monsoonal circulation in the early Holocene. The Loon Lake record implies that the location of contrasting climate regimes did not change in the Yellowstone region during the Holocene. The amplitude of the regimes, however, was determined by the intensity of circulation features and these varied with temporal changes in the seasonal distribution of solar radiation.

The Late Pleistocene and Holocene Vegetational History of Hunter Island, North-Western Tasmania

1978 ◽  
Vol 26 (4) ◽  
pp. 493 ◽  
Author(s):  
GS Hope
Keyword(s):  
Late Pleistocene ◽  
Pollen Analysis ◽  
Human Occupation ◽  
The Holocene ◽  
South Eastern ◽  
Eastern Australia ◽  
History Of ◽  
Scattered Trees ◽  
Arid Steppe ◽  
North Western

Cave Bay Cave contains pollen-bearing sediments derived partly from weathering of the roof and partly from intermittent human occupation. These span the periods c. 28,000-14,700 B.P. and c. 8000 B.P. to the present. Pollen analysis of the Pleistocene sediments indicates that an initial open shrubland was followed by grassland which became increasingly open with abundant composites. Eucalypts occurred in the area but were probably very sparse. The Holocene section records a coastal shrubland like that at present in the area. Intervals of occupation appear to have had little effect on vegetation recorded at the cave, but fires occurred in the vegetation during unoccupied as well as occupied phases. Comparison of the Pleistocene spectra with those from sites in near-coastal Tasmania and south-eastern Australia suggest that an open grassland with scattered trees was extensive from the Adelaide region down to the Bassian Plain. Some components of this cold steppe formation may occur today in the treeline woodlands on the driest parts of the Tasmanian mountains, but there may also be floristic affinities with arid steppe. The grassland probably reflects conditions colder, drier and possibly windier than any represented in the area today.

Sign in / Sign up

Export Citation Format

Share Document