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Geological Correlation, 2007, 15(4): The Pleistocenesediments of North European Russia havebeen studied using different methods to estaThe Pleistocene sediments of North EuropeanRussia have been studied using different methodsto establish their composition and identifythe enclosed organic remains. The results obtainedelucidate natural climatic environments ofthe Pleistocene and corresponding sedimentationcycles and development stages. Glaciation centersare identified for different Pleistocene epochsbased on lithological criteria. The establishedsecular trends characterizing spatial distributionand composition of different-age glacialhorizons facilitate their regional correlation.Climatic conditions and paleogeographic settingsof sedimentation during interglacial epochsof the middle-late Pleistocene and Holocene arereconstructed. Variations in development ofvegetation, temperature, and humidity are detectedfor the first time in the Timan-Pechora-Vychegda, Arkhangel’sk and Vologda regionswith parallel coordination of obtained data. As isconcluded, there was a tendency of climate coolingin North European Russia during the Neopleistocene.2008040586中 国 西 北 地 区 柴 达 木 盆 地 库 尔 雷 克 湖 全 新 世植 被 和 气 候 历 史 = Holocene vegetation andclimate history at Hurleg Lake in the QaidamBasin, northwest China. ( 英 文 ). Zhao Yan; YuZicheng; Chen Fahu; Ito E; Zhao Cheng. Reviewof Palaeobotany and Palynology, 2007, 145(3-4):275-288We present fossil pollen data and discuss theirclimatic interpretations from a 688-cm-longsediment core from Hurleg Lake, a freshwaterlake located in the Qaidam Basin on the NE TibetanPlateau, just beyond the northern limit ofthe East Asian summer monsoon influence. Thereconstruction of the Holocene vegetation andclimate history was aided by modern surfacepollen analysis. The 14000-yr chronology of thesediment core was controlled by seven AMS 14 Cdates on plant macrofossils. The results of thesurface pollen analysis showed that modern pollenspectra faithfully reflect the regional vegetationalong a transect from alpine meadow to desertsteppe and desert, so fossil pollen record canbe used to reconstruct Holocene vegetationchange. The pollen data showed that vegetationchanged from desert before the Holocene to desertsteppe dominated by Artemisia from 11.9 to9.5 ka, desert dominated by Chenopodiaceaefrom 9.5 to 5.5 ka, and steppe desert dominatedby Artemisia and Poaceae after 5.5 ka. Thisvegetation sequence indicates that climate wasrelatively wet before 9.5 ka, dry and variablefrom 9.5 to 5.5 ka, and relatively wet and stableafter 5.5 ka. The climate pattern reconstructedfrom pollen data appears to be opposite to thepaleoclimate pattern inferred at Qinghai Lake,300 km east of our study site. That site shows amoist early Holocene during the insolation andmonsoon maximum followed by a drying trendduring the mid- and late Holocene. The contrastbetween the two sites suggests the importance ofthe position of the subtropical monsoon, themid-latitude westerlies and interactions betweenlocal topography and regional climate. Our findinghas important implications for understandingcomplex regional vegetation and climate responsesto large-scale forcings in arid centralAsia.2008040587罗 马 尼 亚 末 次 冰 期 孑 遗 居 群 的 影 响 和 早 全 新世 植 被 的 变 迁 = The influence of refugial populationon Lateglacial and early Holocene vegetationalchanges in Romania. ( 英 文 ). Feurdean A;Wohlfarth B; Björkman L; Tantau I; Bennike O;Willis K J; Farcas S; Robertsson A M. Review ofPalaeobotany and Palynology, 2007, 145(3-4):305-320Romania has for a long time been lackinggood palaeoenvironmental records, particularlyfor the Late Quaternary. A chronological frameworkhad been nearly absent and the vegetationdevelopment had been reconstructed entirelyfrom pollen data. Data sets from this part ofEurope are important for assessing the spatialvariability of past vegetation and climaticchanges and to reconstruct tree migration routesat the end of the last glacial period. New palaeobotanicalevidence has enabled us to addressthis gap and to provide a more comprehensivepicture of the Lateglacial and early Holocenecontinental environment. This paper reviewsresults from radiocarbon dated sequences inRomania with the aim to place them in a largerperspective with regard to glacial refugia andtree immigration, and to asses the vegetationresponse to climatic oscillation from the end ofthe Last Glacial Maximum (LGM) to the earlyHolocene. This study documents that some coniferousand broad-leaved trees were presentprior to 14,700 cal. yr BP in Romania, and thusit appears that this region may have been a refugialarea for some tree species. During the Lateglacial,the vegetation shows a distinct responseto climatic oscillations at all elevations, althoughthe response is stronger at mid altitude (800–1100 m. a.s.l) than at high altitudes. Moreover,smaller climatic oscillations are only recorded atsites situated at mid altitudes, probably becausethese areas were located close to the tree lineecotone.2008040588177