Compte-rendu synthétique de tous les diagrammes palynostratigraphiques connus du sud-ouest du Yukon. La plupart des séquences datent de l'Holocène. Mise en évidence de la colonisation de la région par l'épinette.
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.
Diagramme pollinique ; Dépôt de pente ; Espagne ; Galicia ; Holocène ; Infiltration ; Micromorphologie ; Palynologie ; Paléo-environnement ; Paléo-écologie ; Quaternaire ; Sol ; Tardiglaciaire
Comparison of the sequence of pollen associations of soil profiles with pollen zones of reference diagrams offers palyno-ecological information, relevant for reconstruction of landscape ecological development. Interpretation of soil pollen
associations requires knowledge of the processes of infiltration and conservation of pollen grains in the soil material. Micromorphology is an important technique to investigate these processes. This is demonstrated in a case study of polycyclic slope deposits
Modern alluvial pollen varies with geomorphic setting and depositional facies in sediments of the Yellow, Hutuo, and Luan rivers and in Baiyangdian and Hengshuihu lakes. Alluvium dominated by Pinus pollen and Selaginella spores was deposited during
a flood. In reconstructing the ancient vegetation and past climate based on pollen in alluvium, it is important to consider sedimentary facies and geomorphologic setting.
A Late-Quaternary pollen record from Ka'au Crater, O'ahu, Hawai'i
C 14 dating ; Hawaii ; Lateglacial ; Palaeoclimate ; Palynology ; Pollendiagram ; Quaternary ; Tropical zone
Datation C 14 ; Diagramme pollinique ; Hawaii ; Palynologie ; Paléoclimat ; Quaternaire ; Tardiglaciaire ; Zone intertropicale
A pollen record from Ka'au Crater, O'ahu, Hawai'i contains evidence for changes in vegetation and climate since about 28,000 C 14 yr B.P.. Climate reconstruction was based on modern climatic ranges of flowering plants and an index derived from
abundance of pollen in surface samples. The pollen-derived temperature index yields an estimate of 3°-5°C temperature depression during the last glacial maximum.
Pollen evidence from Lake Shayema, Mianning County, was obtained to examine postglacial vegetation and climatic change in southwestern Sichuan. The pollen record displays several changes in the vegetation over the last 11 000 yr. Except
for increased disturbance starting ca. 1 000 yr B.P., the predominance of sclerophyllous vegetation continued until today. The pollen results are compatible with proposed global circulation hypotheses of a strengthened monsoon system during the early to mid
Etude de la relation pollen-végétation dans les montagnes du Qilian situées dans la zone de transition du Plateau du Tibet, du Plateau de Loess et de la région aride de la Chine du Nord-Ouest qui est l'une des zones clés du changement global de
La fluctuation des fréquences des pollen dans les dépôts alluviaux est liée à la sédimentologie et ne reflète pas la végétation locale ou régionale de l'époque du dépôt des sédiments. Les pollen alluviaux ne peuvent pas être utilisés pour la
Paleoenvironmental changes dating back to 30,000 yr B.P. documented in a pollen record from central Brazil (lat. 19o S) permit the reconstruction of climatic changes related to shifts of the Antarctic polar fronts. The paleoclimatic inferences were
obtained by a study of modern vegetation and pollen distribution, taking into account present-day climatic parameters.
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.
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
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.
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.
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 ; Pollendiagram ; Twentieth Century
Cores of the uppermost laminated sediment were taken from 3 locations along Lake Paanajärvi, for fine-scale pollen study. The pollendiagrams 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
Lake Johnston cirque contains some of the best subalpine rainforest in Tasmania. The vegetation composition was studied to determine locally sourced pollen inputs and to interpret the pollendiagram. Magnetic measurements of mineral properties
La première partie présente les grains de pollen et les techniques de l'analyse palynologique des sédiments plio-quaternaires. La seconde, sur le cas de l'Europe et de l'Afrique, traite des applications de la palynologie à l'étude des environnements
This study reports on pollen analyses from a series of lakes on Somerset Island in the Canadian Arctic. The results suggest a climatic deterioration during the past 6000 yr which has caused a decrease in the abundance of plants on the landscape.
This paper presents a 40,000-yr pollen- and diatom-based paleoenvironmental record from a crater lake, Tritrivakely, in the Madagascar highlands. It aims at understanding the response of a southern tropical land area to changes in solar radiation
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 ; Pollendiagram ; 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.
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)