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Rapid climatic change in coastal Southern California inferred from pollen analysis of San Joaquin marsh

Rapid climatic change in coastal Southern California inferred from pollen analysis of San Joaquin marsh
C14 dating ; California ; Climatic variation ; Paleo-environment ; Palynology ; Pollen diagrams ; Quaternary ; United States
Pollen analysis and five radiocarbon dates of a 687-cm core provide a detailed chronology of environmental change in a marsh at the head of Newport Bay, Orange County, California. Results and discussion.

Pollen and spore stratigraphy of a mollic hapludalf (degraded chernozem) in Northeastern Kansas

Pollen and spore stratigraphy of a mollic hapludalf (degraded chernozem) in Northeastern Kansas
Type, origine et répartition des pollens et spores. Problèmes de migration du pollen dans le sol. Pédoturbation.

Dissimilarity mapping between fossil and contemporary pollen spectra in Europe for the past 13,000 years
The aims of this study are : 1) to evaluate quantitatively the extent to which European pollen spectra for the last 13,000 years represent vegetation units lacking modern analogs| 2) to map the location and extent of no-analog vegetation
at millenial intervals| and 3) to display the patterns, extent, and rates of change of pollen spectra, and hence, by inference, of vegetation and macroclimate, in Europe during the last 13,000 years. The degree of analogy between fossil and contemporary pollen

Climatic change at the end of the last glaciation in Japan inferred from pollen in three cores from the Northwest Pacific Ocean

Climatic change at the end of the last glaciation in Japan inferred from pollen in three cores from the Northwest Pacific Ocean
The AA. examine paleoclimatic evidence from northeast Asia. The primary data are pollen time-series from three high sedimentation-rate marine cores from which a cooling event described as coeval with the Younger Dryas Chronozone has been identified
from oxygen isotope and microfaunal records. These marine pollen records are then compared with pollen data from representative late-glacial Japanese records.

Late Quaternary vegetational and climatic changes in the Pampa grassland of Argentina

Argentina ; Atmospheric circulation ; Climatic variation ; Ecosystem ; Global change ; Model ; Palaeoclimatology ; Palynology ; Pampa ; Pollen diagram ; Quaternary
This study reconstructs past plant communities in the pampa grassland for the late Quaternary, to infer regional paleoclimatic trends, and to relate these trends to global changes in atmospheric circulation. Several dated pollen records were anlyzed
and interpreted using modern pollen spectra. The comparison of fossil pollen sequences with modern pollen provided information about changes in the composition and distribution of late Quaternary vegetation.

A late-glacial/Holocene pollen record from the Eastern Andes of Northern Peru

A late-glacial/Holocene pollen record from the Eastern Andes of Northern Peru
Andes ; C 14 dating ; Climatic variation ; Holocene ; Human impact ; Lacustrine sedimentation ; Lateglacial ; Palaeo-ecology ; Palynology ; Peru ; Pollen diagram ; Quaternary
The objectives of this study are to look for evidence of late-glacial and Holocene climatic fluctuations in the fossil pollen and sedimentological record from Laguna Baja, and to examine the fossil pollen record for evidence of human impact

Long Pleistocene pollen records from the Praclaux crater, south-central France

Long Pleistocene pollen records from the Praclaux crater, south-central France
France ; Haute-Loire ; Interglacial ; Lacustrine sediment ; Palaeo-environment ; Palynology ; Pleistocene ; Pollen diagram ; Quaternary ; Stratigraphic correlation ; Tephrochronology
A 46-m core of lake sediments, obtained from the center of the explosion crater of Praclaux (Haute-Loire, Velay, France), was studied on the basis of 368 pollen spectra. Five temperate forest episodes alternating with phases indicative of glacial
climates are recorded. A thick trachytic tephra permits correlation to be established with the pollen sequence from Lac du Bouchet.

A Holocene ice-core pollen record from Ellesmere Island, Nunavut, Canada

A Holocene ice-core pollen record from Ellesmere Island, Nunavut, Canada
Arctic Region ; Atmospheric circulation ; Canada ; Ellesmere ; Forest ; Holocene ; Northwest Territories ; Palaeo-environment ; Palynology ; Pollen diagram ; Quaternary
The objectives of this study are to present a more reliable pollen profile for the Agassiz Ice Cap, Ellesmere Island, and to establish the paleoenvironmental significance of the record. This investigation adds to a short list of contributions
on the pollen content of ice cores retrieved in Arctic regions.

L'analyse pollinique des stalagmites: une nouvelle possibilité d'approche des fluctuations climatiques du Quaternaire

The application of the most recent techniques of pollen extraction allows a sufficient number of pollen grains to be obtained from stalagmites and to construct pollen diagrams based on a significant number of grains. The transport of pollen through
fissured calcareous rocks, by infiltrating water, produces pollen assemblies which reflect the development of the local vegetation. The growth of the stalagmites is not restricted to interglacials: among the six stalagmites studied, three were formed during

Paläobotanische Archive : Jungquartäre und holozäne Klimaentwicklung in chinesischen Trockengebieten

Arid area ; Botany ; China ; Climate ; Palaeo-environment ; Pollen analysis ; Sedimentary ; Vegetation
Pollen analysis as a technique for reconstructing former vegetation by means of fossil pollen grains preserved in the sediments was ´born´ in 1916, when Swedish geologist Lennart von Post (1884-1951) presented the first percentage pollen diagram
at the meeting of the Swedish Geological Society, held in Kristiana (now Oslo). A combination of the following unique features makes pollen analysis such a useful tool for palaeoenvironmental studies: (a) plants produce pollen in great quantities; (b) pollen
grains are easily dispersed by wind, water or insects and occur in almost all types of sediments on all continents except Antarctica; (c) the outer coat of pollen grain build of the biopolymer sporopollenin is extremely resistant to mechanical
and chemical agents and well preserved even in very old sediments; (d) a great quantity of pollen grains representing past vegetation which grew around the sampling site can be easily recovered from fossil sediments; (e) most of the pollen grains recovered from
Quaternary deposits can be identified to the species, family level and the resulting pollen assemblage allows statistical treatment. - (IfL)

The global pollen database in biogeographical and palaeoclimatic studies

The global pollen database in biogeographical and palaeoclimatic studies
Amérique du Nord ; Base de données ; Biogéographie ; Canada ; Carbone ; Cartographie ; Colonisation végétale ; Diagramme pollinique ; Dynamique de la végétation ; Holocène ; Monde ; Palynologie ; Paléo-écologie ; Paléoclimatologie ; Pollen
Biogeography ; Canada ; Carbon ; Cartography ; Data base ; Holocene ; North America ; Palaeo-ecology ; Palaeoclimatology ; Palynology ; Plant colonization ; Pollen ; Pollen diagram ; Taxonomy ; Vegetation dynamics ; World
In this review the AA. discuss some recent work that has been accomplished using the North American Pollen Database (NAPD). After briefly summarizing some of the more standard uses, including plotting the migration of plant taxa, or mapping past
of the perceived limitations of pollen data being circumvented by use at the appropriate level of analysis.

Évolution récente de la répartition géographique des plantes émettrices de pollen allergisant et perspectives en liaison avec le changement climatique

Évolution récente de la répartition géographique des plantes émettrices de pollen allergisant et perspectives en liaison avec le changement climatique
Action anthropique ; Aire floristique ; Allergie au pollen ; Bioclimatologie ; Bioclimatologie humaine ; Changement climatique ; Impact ; Pollen ; Santé ; Végétation
Bioclimatology ; Climatic change ; Floristic area ; Health ; Human bioclimatology ; Human impact ; Impact ; Pollen ; Vegetation
Acción antrópica ; Bioclimatología ; Bioclimatología humana ; Cambio climático ; Impacto ; Polen ; Salud ; Vegetación ; Área florística
Le changement climatique pourrait en théorie faciliter la diffusion hors des régions où elles étaient jusque-là présentes de certaines espèces végétales à pollen allergisant. Toutefois, les plantes ne suivent ni automatiquement, ni immédiatement

Untersuchung einer Doline auf dem Zugspitzplatt. Ein palynologischer Beitrag zur holozänen Gletschergeschichte im Wettersteingebirge

Alps (The) ; Bavaria ; Doline ; Germany ; Glacial features ; Glacier fluctuation ; Holocene ; Palaeogeography ; Palynology ; Pollen diagram ; Stratigraphy
The article deals with the doline, the Holocene, the pollen analysis and the Schneeferner glacier of the Zugspitzplatt. The paper describes the pollen analysis in high mountains, the closer pollen collection area, the pollen conversation, the other
pollen spectra, the advisement to dating of the pollen and vegetation history and the humus colluviums in the doling. This is a contribution for discussion of the post-glacial active glacier in Wettersteingebirge. - (IfL)

Late Holocene climatic changes in western equatorial Africa inferred from pollen from Lake Sinnda, southern Congo

Late Holocene climatic changes in western equatorial Africa inferred from pollen from Lake Sinnda, southern Congo
Aridity ; C 14 dating ; Climatic variation ; Congo ; Holocene ; Lacustrine sediment ; Palaeoclimate ; Palynology ; Pollen diagram
Pollen analysis of 2 cores from the Lake Sinnda, located in one of the driest areas of the southern Congo, reveals a history of vegetation and climate in this region during the past 5000 yr. A major change centered around 3000-2500 yr B.P
. is indicated by an abrupt decrease in forest pollen and by a corresponding increase in grassland pollen. Concurrent drying up of the lake shows that climate, in particular aridity, was the major cause of this change. The aridity predates agriculture marked
by pollen of the oil palm at Lake Sinnda.

Climatic reconstruction in Europe for 18,000 yr B.P. from pollen data

Climatic reconstruction in Europe for 18,000 yr B.P. from pollen data
This paper proposes a new method of reconstructing past climate from pollen data, which is applicable to other continents as well as Europe. In order to deal with the lack of perfect analogs of fossil assemblages, the AA. used a combination
of pollen types grouped according to plant phenology and present climate constraints rather than pollen percentages for each individual taxon. The distribution of pollen taxa into plant functional types (PFTs) is aimed to reflect the vegetation in terms
of biomes. The climatic variables are then calibrated on these PFTs using an artificial neural network technique. The method is applied to the glacial steppic vegetation in Europe, using 15 pollen records.

A Late Wisconsin and Holocene vegetation history from the central Brook Range: implications for Alaskan palaeoecology

New insights into the vegetation history of this region are provided by calculations of pollen influx and by the use of linear discriminant analysis to separate Picea glauca and P. mariana pollen. Three major pollen zones are identified: (1) a basal
herb zone, characterized by high percentages of Cyperaceae, Gramineae, Salix, and Artemisia, and low total pollen influx| (2) a shrub Betula zone with increased total pollen influx and very high percentages of Betula pollen, predominantly in the size
range of B. nana and B. glandulosa| and (3) an Alnus zone dominated by Alnus pollen.

The pollen record of human influence at Paanajärvi

The pollen record of human influence at Paanajärvi
Agricultural land use ; European part of Russia ; Finland ; Frontier ; Historical geography ; Holocene ; Human impact ; Karelia ; Lacustrine sediment ; Lake ; Palaeo-ecology ; Palynology ; Pollen diagram ; Twentieth Century
Cores of the uppermost laminated sediment were taken from 3 locations along Lake Paanajärvi, for fine-scale pollen study. The pollen diagrams can be correlated with the written history of the area. The wars and peace treaties that affected
the frontier between Finland and Russia, now 3,5 km west of the lake, affected the settlements and thus the pollen sequence. From the correlations it is clear that the Karelians were the first around Paanajärvi to use cultivated grasses and a slash-and-burn

Late Quaternary vegetation and climate change in the Amazon Basin based on a 50,000 year pollen record from the Amazon Fan, ODP Site 932

Late Quaternary vegetation and climate change in the Amazon Basin based on a 50,000 year pollen record from the Amazon Fan, ODP Site 932
Alluvial cone ; Amazonas River ; Atlantic Ocean ; Climatic variation ; Holocene ; Isotope analysis ; Marine sediment ; Oxygen 18 ; Palaeo-ecology ; Palynology ; Pollen diagram ; Quaternary ; South Atlantic Ocean ; Tropical rain forest ; Watershed
The aim of this study is to compare the modern Amazon River pollen discharge and terrestrial fossil pollen records with high-resolution fossil pollen and stable isotope records from the Amazon Fan so as to reconstruct the vegetation of the Amazon

A 12,000-year pollen record from Lake Maliq, Albania

A 12,000-year pollen record from Lake Maliq, Albania
Albania ; C 14 dating ; Forest ; Geochronology ; Holocene ; Lacustrine sediment ; Lateglacial ; Palaeo-environment ; Palaeoclimate ; Palynology ; Pollen diagram ; Quaternary
The AA. present here the first pollen data from Albania. They come from lacustrine and peat deposits cored in former Lake Maliq in the Korçë basin at an altitude of 818 m. When compared with other pollen sites in northwestern Greece, the Maliq
pollen data allow the completion of an altitudinal transect between 285 and 1800 m and provide a new interpretation involving the composition and subsequent development of ecosystems at middle altitude in the Balkans for the past 12,000 years.

Calibrating pollen data in climatic terms: improving the methods

Calibrating pollen data in climatic terms: improving the methods
Multiple linear regression of modern climate and pollen data allows the development of statistical calibration functions that transform percentages of certain pollen types into quantitative estimates of climatic variables, and these functions, when
applied to Holocene pollen data, yield estimates of climatic variables for past times. We outline the steps to be followed in calculating calibration functions. We used available computer programs for most of this study. In addition, we developed new
used data from the lower peninsula of Michigan to develop a calibration function for July mean temperature and then used Holocene pollen data from central lower Michigan to estimate past temperatures.

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