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  • Quaternary pollen analysis : recent progress in palaeoecology and palaeoclimatology
  • Bibliography ; Climate reconstruction ; Methodology ; Model ; Palaeo-ecology ; Palaeoclimatology ; Palynology ; Pollen analysis ; Quaternary
  • During the last decade Quaternary pollen analysis has developed towards improved pollen-taxonomical precision, automated pollen identification and more rigorous definition of pollen assemblages zones. There have been significant efforts to model
  • the spatial representation of pollen records in terms of past vegetation patterns. The AA. review the difficulties in matching modelled post-glacial plant migration patterns with pollen-based palaeorecords and discuss the potential of DNA analysis of pollen
  • Prospects for Quaternary pollen research in China.
  • Development in pollen research is needed in three directions. Firstly, mastery of vegetational knowledge, identification of regularities of pollen dispersal in various geographical conditions| secondly, improvement in techniques of pollen analysis
  • , using the absolute pollen concept to rationalise zonation work, and in numerical techniques| thirdly, in application recognise the benefit of infiltration and coordination with related sciences. (TNC).
  • Spatial patterns of atmospheric pollen transport in a montane region
  • Annual pollen deposition was sampled for 6 yr in the southern Sierra Nevada, the Owens Valley, and the Inyo Mountains of central California. The step function that seems to characterize pollen distribution patterns implies that pollen from distant
  • population may be of little value in interpreting vegetation stability and change reflected by fossil pollen stratigraphy. The physical isolation of pollen embedded in the local mountain-valley wind system from that in the prevailing westerlies may explain
  • part of the spatial distribution of the pollen.
  • Formations végétales et pollens
  • Bogs and lacustrine deposits are the best traps for pollens. But the identification at the level species is impossible and the pollen spectrum is never the exact reflect of the contemporaneous vegetation.
  • Surface pollen in the east of Qaidam Basin
  • Analyse en composantes principales ; Analyse pollinique ; Aridité ; Beijing ; Biogéographie ; Chine ; Climat ; Corrélation ; Paléo-environnement ; Pollen ; Quaternaire ; Végétation
  • Aridity ; Beijing ; Biogeography ; China ; Climate ; Correlation ; Palaeo-environment ; Pollen ; Pollen analysis ; Principal components analysis ; Quaternary ; Vegetation
  • Pollen analysis of 23 surface samples in the east of Qaidam Basin reveals the characteristics of pollen assemblages and their relationships with vegetation and climate. Depending on the aridity, the vegetation communities are divided into 4 groups
  • Pollen representation, source area, and basin size: toward a unified theory of pollen analysis
  • The concepts of pollen source area and of production and dispersal biases in pollen representation are quantified by means of a simple theoretical model. Source areas and relative pollen representation are shown to depend on basin size according
  • to functions that describe the amount of pollen remaining airborne at increasing distances from single pollen sources. The integrated form of Sutton's equation for particle dispersal from a ground-level source gives usefull approximations applicable to pollen
  • Pollen taphonomy in a canyon stream
  • Arizona ; Canyon ; Diagramme pollinique ; Etats-Unis ; Granulométrie ; Géographie physique ; Pollen ; Sédimentologie ; Taphonomie ; Végétation
  • 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
  • Contemporary pollen spectra and vegetation of the Nyika Plateau, Malawi
  • A study of contemporary pollen rain on the Nyika Plateau reveals that both pollen hap and surface spectra reflect the present day vegetation pattern very closely. Fossil pollen spectra can be expected to give a good indication of regional changes
  • The use of micromorphology in soil pollen analysis. The interpretation of the pollen content of slope deposits in Galicia, Spain
  • Galicia ; Holocene ; Infiltration ; Lateglacial ; Micromorphology ; Palaeo-ecology ; Palaeo-environment ; Palynology ; Pollen diagram ; Quaternary ; Slope deposit ; Soil ; Spain
  • 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
  • Influence des facteurs météorologiques sur la concentration du pollen dans l'air
  • Atmosphère ; Bourgogne ; Calendrier pollinique ; Corrélation ; France ; Météorologie ; Palynologie ; Pollen ; Végétation
  • Atmosphere ; Burgundy ; Correlation ; France ; Meteorology ; Palynology ; Pollen ; Vegetation
  • L'air renferme très peu de pollen par temps pluvieux, ainsi qu'en présence de fortes amplitudes journalières de l'humidité relative, de calmes atmosphériques et de gel. A l'inverse, un temps chaud et ensoleillé, des vents de 2 à 5 m/s et une
  • amplitude journalière de l'humidité relative comprise entre 30 et 50% sont propices à de fortes concentrations de pollen. - (JPB)
  • Preliminary studies on air-borne spores and pollens in northern suburb of Beijing
  • Allergie ; Atmosphère ; Beijing ; Bioclimatologie ; Chine ; Circulation atmosphérique ; Mousson ; Palynologie ; Pollen ; Spore ; Variation saisonnière
  • Atmosphere ; Atmospheric circulation ; Beijing ; Bioclimatology ; China ; Monsoon ; Palynology ; Pollen ; Seasonal variation
  • This paper focuses on air-borne sporo-pollen content and its variations throughout 1979, and discusses spore content of certain microorganisms and its variations. The amount of air-borne plant pollen and bacterial spores is much higher in hot sunny
  • Alluvial pollen on the North China Plain
  • Alluvium ; China ; Flood ; Floodplain ; Monsoon ; Northern China ; Palaeo-environment ; Palynology ; Plain ; Pollen diagram ; Quaternary
  • 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 ; Pollen diagram ; Quaternary ; Tropical zone
  • 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 of changing Holocene monsoon climate in Sichuan Province, China
  • Atmospheric circulation ; China ; Climatic variation ; Holocene ; Monsoon ; Palaeogeography ; Palynology ; Pollen diagram ; Quaternary ; Sichaun ; Vegetation
  • 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
  • A model of pollen source area for an entire lake surface
  • This paper describes a model for pollen deposition integrated over an entire lake surface, and it estimates the source area of major pollen types for various lake sizes. It is a modification of Prentice's (1985, 1988) model, which estimates
  • the source area of pollen deposited at a point in the center of a sedimentary basin. Comparison of the results from the two models displays the potential differences in pollen source areas when a bog and a lake of similar size are considered.
  • Surface pollen and its relationship to vegetation on the southern slope of the eastern Qilian Mountains
  • Chine ; Corrélation ; Diagramme pollinique ; Montagne ; Pollen ; Qilian ; Végétation
  • China ; Correlation ; Mountain ; Pollen ; Pollen diagram ; Vegetation
  • 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
  • Pollen analysis of snow samples from the North Pole region
  • Analyse pollinique ; Arctique ; Circulation atmosphérique ; Glace de mer ; Neige ; Pollen ; Russie ; Russie du Nord
  • Arctic Region ; Atmospheric circulation ; Northern Russia ; Pollen ; Pollen analysis ; Russia ; Sea ice ; Snow
  • Analyse pollinique d'échantillons de neige de glace de mer collectés en avril-mai 2002 par les membres de la Station Polaire de Russie du Nord-2001. En déterminant les espèces de plantes représentées par ces pollens et spores, on peut obtenir des
  • Comparison of air-borne pollen at Louvain-la-Neuve (Belgium) and Basel (Switzerland) during 1979 and 1980
  • The pollen production for both years was three times higher in Basel than at Louvain-la-Neuve. The interpretation of the pollen calendars showed an average onset of eight days earlier in 1979 and five days earlier in 1980 for the taxa in Basel
  • . The pollen catch for both stations was greater in 1980 than in 1979, which was characterized by an average delay in the onset of pollen shedding both in Basel and at Louvain-la-Neuve. (Les AA.).
  • Modern pollen-rain characteristics of tall terra firme moist evergreen forest, southern Amazonia
  • Amazonie ; Bolivie ; Forêt tropicale ; Palynologie ; Paléo-écologie ; Pollen ; Quaternaire ; Taxonomie ; Variabilité interannuelle ; Variation spatiale ; Zone intertropicale
  • Amazon Basin ; Bolivia ; Interannual variability ; Palaeo-ecology ; Palynology ; Pollen ; Quaternary ; Spatial variation ; Taxonomy ; Tropical rain forest ; Tropical zone
  • Here, the AA. present the first modern pollen-rain data for tall terra firme moist evergreen Amazon forest, collected between 1999 and 2001 from artificial pollen traps in Noel Kempff Mercado National Park (NE Bolivia). Spearman's rank correlations
  • were performed to assess the extent of spatial and inter-annual variability in the pollen rain, whilst statistically distinctive data were identified using Principal Components Analysis (PCA). Comparisons which the floristic and basal area data
  • of the plot enabled the degree to which taxa are over/under-represented in the pollen rain to be assessed.
  • LEAD-210 AND POLLEN GEOCHRONOLOGIES ON LAKE SUPERIOR SEDIMENTS
  • LES VITESSES DE SEDIMENTATION, DANS DEUX DEPOTS DU LAC SUPERIEUR ONT ETE DETERMINEES PAR L'ETUDE DU POLLEN DE JACOBEE ET LA GEOCHRONOLOGIE AU PB. L'APPARITION DU POLLEN DE JACOBEE EST LIEE A L'ETABLISSEMENT HUMAIN ET SE SITUE AUX ALENTOURS DE 1830.