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.

Phylogeography and ecological niche modelling, coupled with the fossil pollen record, unravel the demographic history of a Neotropical swamp palm through the Quaternary

2014 ◽  
Vol 41 (4) ◽  
pp. 673-686 ◽  
Author(s):  
Natácia Evangelista de Lima ◽  
Matheus S. Lima-Ribeiro ◽  
Carla Faleiro Tinoco ◽  
Levi Carina Terribile ◽  
Rosane G. Collevatti
Keyword(s):  
Ecological Niche ◽  
Demographic History ◽  
Ecological Niche Modelling ◽  
Fossil Pollen ◽  
Pollen Record ◽  
Niche Modelling ◽  
History Of

scholarly journals Vegetation and climate dynamics in Khyber Pakhtunkhwa (NW Pakistan), inferred from the pollen record of the Kabal Valley in Swat District during the last 3300 years

2019 ◽  
Vol 59 (1) ◽  
pp. 145-163
Author(s):  
Farooq Jan ◽  
Lisa Schüler ◽  
Fayaz Asad ◽  
Hermann Behling
Keyword(s):  
Vegetation History ◽  
Agricultural Activity ◽  
Pollen Record ◽  
Conifer Forest ◽  
Khyber Pakhtunkhwa ◽  
Hindu Kush ◽  
History Of ◽  
Khyber Pakhtunkhwa Province ◽  
Trees And Shrubs ◽  
Vegetation And Climate

Abstract We present a pollen-based palaeoenvironmental reconstruction of the past 3300 years in the Kabal Valley of Swat District in the Hindu Kush mountains of Khyber Pakhtunkhwa Province, north-western Pakistan. We studied the pollen record from 38 samples taken from a 150 cm long radiocarbon-dated sediment core in order to analyse the vegetation history of the area. Only the upper 76 cm of the core, with 20 samples recording the last 3300 years, had sufficiently preserved pollen. Conifers such as Pinus, Picea, Abies, Cedrus and Taxus, and herbs belonging to Poaceae, Cyperaceae and Amaranthaceae were found consistently throughout the period, at varying abundance. The vegetation reconstruction revealed that Cyperaceae and Poaceae dominated the conifers from 3300 to 300 cal yr BP. The decrease in herbaceous vegetation (mainly Poaceae) from 2400 to 1500 cal yr BP, and its increase from 1500 to 1200 cal yr BP, indicate contraction followed by expansion of grassland in the Kabal Valley of Swat, pointing to corresponding dry-cool and wet-warm periods. Herbs were abundant in most samples from 900 to 300 cal yr BP. This change from conifer forest to open grassland can be attributed to the more pronounced impact of widespread deforestation, agricultural activity and a drier summer climate. Evergreen trees and shrubs such as Oleaceae, Myrtaceae, Moraceae species, Juglans and Dodonaea dominated and were constant from 2400 cal yr BP to the present. Conifers such as Pinus, Taxus, Picea, Abies and Cedrus were frequent in the study area from 300 cal yr BP to the present. Today these conifers occur mostly in mixed coniferous forests at higher elevation in the alpine area.

A 14,000 year vegetation history of a hypermaritime island on the outer Pacific coast of Canada based on fossil pollen, spores and conifer stomata

2012 ◽  
Vol 78 (3) ◽  
pp. 572-582 ◽  
Author(s):  
Terri Lacourse ◽  
J. Michelle Delepine ◽  
Elizabeth H. Hoffman ◽  
Rolf W. Mathewes
Keyword(s):  
Pinus Contorta ◽  
Vegetation History ◽  
Tsuga Heterophylla ◽  
Picea Sitchensis ◽  
Thuja Plicata ◽  
North Coast ◽  
Pollen Record ◽  
The North ◽  
History Of ◽  
Local Species

AbstractPollen and conifer stomata analyses of lake sediments from Hippa Island on the north coast of British Columbia were used to reconstruct the vegetation history of this small hypermaritime island. Between 14,000 and 13,230 cal yr BP, the island supported diverse herb–shrub communities dominated by Cyperaceae, Artemisia and Salix. Pinus contorta and Picea sitchensis stomata indicate that these conifers were present among the herb–shrub communities, likely as scattered individuals. Transition to open P. contorta woodland by 13,000 cal yr BP was followed by increases in Alnus viridis, Alnus rubra and P. sitchensis. After 12,000 cal yr BP, Pinus-dominated communities were replaced by dense P. sitchensis and Tsuga heterophylla forest with Lysichiton americanus and fern understory. Thuja plicata stomata indicate that this species was present by 8700 cal yr BP, but the pollen record suggests that its populations did not expand to dominate regional rainforests, along with Tsuga and Picea, until after 6600 cal yr BP. Conifer stomata indicate that species may be locally present for hundreds to thousands of years before pollen exceed thresholds routinely used to infer local species arrival. When combined, pollen and conifer stomata can provide a more accurate record of paleovegetation than either when used alone.

Holocene history of a raised bog, northern New Zealand, based on plant cuticles

The Holocene ◽  
2016 ◽  
Vol 27 (2) ◽  
pp. 309-314 ◽  
Author(s):  
Carolin Haenfling ◽  
Rewi Newnham ◽  
Andrew Rees ◽  
Ignacio Jara ◽  
Aline Homes ◽  
...  
Keyword(s):  
New Zealand ◽  
Vegetation History ◽  
Pollen Grains ◽  
Plant Cuticle ◽  
Pollen Record ◽  
Raised Bog ◽  
Local Site ◽  
Pollen Types ◽  
Plant Cuticles ◽  
History Of

We present a method for analysing subfossil plant cuticles preserved in peat and apply the method to provide a preliminary, coarse resolution reconstruction of Holocene vegetation history at Moanatuatua Bog, northern North Island, New Zealand. The plant cuticle record reveals the early-Holocene development of a swamp and its transition to a raised bog, which is not apparent from other proxies. Comparison with a pollen record from the same sequence highlights the advantages of plant cuticle analysis in cases where pollen is hard to identify or poorly preserved. In particular, distinguishing between the pollen grains of the two main bog species, the restiads Empodisma robustum and Sporadanthus ferrugineus, relies on subtle gradational characteristics, whereas their cuticular patterns are very distinct. Furthermore, Cyperaceae pollen is poorly preserved at Moanatuatua Bog, being almost completely absent, whereas the Cyperaceae cuticles are present throughout the sequence. Therefore, we suggest that Cyperaceae pollen at this site is a less reliable indicator of local sedge communities than the cuticle record. The wide dispersal capabilities of these wind-dispersed pollen types also make them less suitable for determining local site vegetation and environmental change in comparison with cuticle remains. These results suggest that plant cuticle analysis may be a useful tool for the reconstruction of long-term vegetation changes from peat sequences, especially when used in concert with palynology. Sample preparation also proved to be fast with little equipment or chemicals needed.

Late Wisconsin and Holocene vegetational history of the Upper Koyukuk region, Brooks Range, AK

1985 ◽  
Vol 63 (3) ◽  
pp. 616-626 ◽  
Author(s):  
Mary E. Edwards ◽  
Patricia M. Anderson ◽  
Harriet L. Garfinkel ◽  
Linda B. Brubaker
Keyword(s):  
Picea Mariana ◽  
Picea Glauca ◽  
Vegetation History ◽  
High Elevation ◽  
Populus Balsamifera ◽  
Before Present ◽  
Brooks Range ◽  
Arrival Times ◽  
Pollen Rain ◽  
Lower Site

Three pollen diagrams provide information on late Wisconsin and Holocene vegetation history at high elevation and midelevations (1000 and 600 m) in the east-central Brooks Range. After the retreat of glacial ice and until about 12 000 years before present, the vegetation was a tundra, dominated by Salix, Cyperaceae, Gramineae, Artemisia, and other herbaceous taxa. However, because the early pollen spectra do not have close modern analogs, the detailed composition and ecology of this tundra cannot be inferred. Between ca. 12 000 and ca. 8 000 years before present, Betula nana–glandulosa was the dominant pollen producer at both elevations; a significant ericaceous component was present in the vegetation of the alpine sites, but not at the lower elevation site. During the period 10 500 – 8 500 years before present, Populus balsamifera and Juniperus were probably abundant at the lower site and may also have been present at the higher sites, where they are now absent. Picea glauca, Alnus spp., Picea mariana, and Betula papyrifera became established at the lower site between ca. 8500 and 6000 years before present. None of these species currently grows at the high sites, but their arrival at lower elevations is represented in the regional pollen rain at these sites. The arrival times of Picea glauca and Picea mariana in the study area are consistent with the hypothesis that P. glauca preceded P. mariana into the central Brooks Range.

Postglacial vegetation history of Mitkof Island, Alexander Archipelago, southeastern Alaska

2010 ◽  
Vol 73 (2) ◽  
pp. 259-268 ◽  
Author(s):  
Thomas A. Ager ◽  
Paul E. Carrara ◽  
Jane L. Smith ◽  
Victoria Anne ◽  
Joni Johnson
Keyword(s):  
Pinus Contorta ◽  
Vegetation History ◽  
Regional Climate ◽  
Sitka Spruce ◽  
Tsuga Heterophylla ◽  
Picea Sitchensis ◽  
Thuja Plicata ◽  
Pollen Record ◽  
Coastal Forests ◽  
History Of

An AMS radiocarbon-dated pollen record from a peat deposit on Mitkof Island, southeastern Alaska provides a vegetation history spanning ∼12,900 cal yr BP to the present. Late Wisconsin glaciers covered the entire island; deglaciation occurred > 15,400 cal yr BP. The earliest known vegetation to develop on the island (∼12,900 cal yr BP) was pine woodland (Pinus contorta) with alder (Alnus), sedges (Cyperaceae) and ferns (Polypodiaceae type). By ∼12,240 cal yr BP, Sitka spruce (Picea sitchensis) began to colonize the island while pine woodland declined. By ∼11,200 cal yr BP, mountain hemlock (Tsuga mertensiana) began to spread across the island. Sitka spruce-mountain hemlock forests dominated the lowland landscapes of the island until ∼10,180 cal yr BP, when western hemlock (Tsuga heterophylla) began to colonize, and soon became the dominant tree species. Rising percentages of pine, sedge, and sphagnum after ∼7100 cal yr BP may reflect an expansion of peat bog habitats as regional climate began to shift to cooler, wetter conditions. A decline in alders at that time suggests that coastal forests had spread into the island's uplands, replacing large areas of alder thickets. Cedars (Chamaecyparis nootkatensis, Thuja plicata) appeared on Mitkof Island during the late Holocene.

Vegetation history of the SE section of the Zagros Mountains during the last five millennia; a pollen record from the Maharlou Lake, Fars Province, Iran

2008 ◽  
Vol 18 (2) ◽  
pp. 123-136 ◽  
Author(s):  
Morteza Djamali ◽  
Jacques-Louis De Beaulieu ◽  
Naomi F. Miller ◽  
Valérie Andrieu-Ponel ◽  
Philippe Ponel ◽  
...  
Keyword(s):  
Vegetation History ◽  
Fars Province ◽  
Pollen Record ◽  
Zagros Mountains ◽  
History Of

The Early History of the Proteaceae in Australia: the Pollen Record

1998 ◽  
Vol 11 (4) ◽  
pp. 401 ◽  
Author(s):  
Mary E. Dettmann ◽  
David M. Jarzen
Keyword(s):  
Early History ◽  
Taxonomic Resolution ◽  
Fossil Pollen ◽  
Pollen Record ◽  
The Family ◽  
North Eastern ◽  
History Of ◽  
Marked Decline ◽  
Species Groups ◽  
Generic Groups

The early history of the Proteaceae in Australia is traced from the record of fossil pollen that possess characters having taxonomic resolution among extant members of the family. Pollen characters useful for segregating subfamilies and generic groups are apertural number and form together with exine stratification and structure. When considered in conjunction with pollen shape, polarity, and size and exine sculpturing, they may be used to discriminate generic and/or species groups. The fossil pollen record suggests that the family originated in northern Gondwana during the late Cenomanian and radiated by as yet unidentified routes into southern high latitudes during the Turonian. There the family underwent substantial differentiation and expansion during Santonian–Maastrichtian times when at least four of the seven extant subfamilies evolved. Although diversification in Australia principally involved rainforest lineages (e.g. Macadamia–Helicia, Carnarvonia, Gevuina) ancestors of some sclerophyllous taxa (e.g. Adenanthos) also differentiated; this occurred in a regionalised vegetation of mesotherm open-forests in which podocarps and araucarians were important. Subsequent (Paleocene–Eocene) diversification and consolidation of the family may have focused on introduction and expansion of sclerophyllous lineages (e.g. Isopogon, Petrophile), but rainforest elements (e.g. Embothrium) were also involved. The associated vegetation, which was regionalised, experienced considerable floristic modifications during this time with introductions and/or expansion of an array of angiosperm taxa, notably Casuarinaceae, Myrtaceae and Nothofagus. In southern regions a marked decline in proteaceous pollen diversity and abundance occurred near the end of the Eocene, whereas in north-eastern regions the decline may have been later, during the Miocene.

scholarly journals Contribution to Early Holocene vegetation and climate history of Eastern Orinoco Llanos, Venezuela, from a paleoecological record of a Mauritia L.f. swamp

2011 ◽  
Vol 41 (4) ◽  
pp. 513-520 ◽  
Author(s):  
Alejandra Leal ◽  
Tibisay Perez ◽  
Bibiana Bilbao
Keyword(s):  
Amazon Basin ◽  
Vegetation History ◽  
Climatic Conditions ◽  
Early Holocene ◽  
Pollen Record ◽  
Climate History ◽  
Palynological Analysis ◽  
Regional Trends ◽  
Pollen Types ◽  
History Of

A palynological analysis of an organic paleosol found at 150-125 cm depth in a Mauritia swamp from the Eastern Orinoco Llanos is presented. The 25 cm pollen record summarizes the vegetation history during the Early Holocene, from 10,225 to 7,800 calendar yr BP. The vegetation was characterized by a Poaceae marsh, where Asteraceae, Melastomataceae, Schefflera-type and Phyllanthus were the most abundant shrubs and trees. Pollen-types richness was lower than that recorded today in similar environments, and Mauritia pollen was absent. Results suggest that climate was as humid as present during the beginning of the Holocene, with a decreasing trend in humidity from around 8,000-7,000 yr BP, in coincidence with the beginning of the "Early-Mid-Holocene Dryness" that affected deeply the Amazon Basin and neighboring areas. Dry climatic conditions could have existed in the study site until the Mid-Late Holocene when a Mauritia swamp developed, and humid conditions similar to present established. Main climate phases inferred in our study site fit well with regional trends recorded in other places located north Amazon Basin. However, conclusions are still limited by the lack of additional Quaternary records in the Orinoco Llanos area, avoiding regional correlations.

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