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意 大 利 北 亚 平 宁 Lamone 谷 植 被 对 早 更 新 世气 候 旋 回 的 响 应 = Vegetation response to earlyPleistocene climatic cycles in the Lamone valley(Northern Apennines, Italy). ( 英 文 ). Fusco F.Review of Palaeobotany and Palynology, 2007,145(1-2): 1-23The vegetation response to cyclic climaticchanges has been investigated by means of pollenanalysis carried out on marine deposits outcroppingin the Lamone valley (Northern Italy).The deposits consist of grey–blue silty–clays ofthe “Argille Azzurre” Formation. Three sedimentarysuccessions, which form the Lamonesection, have been analysed. These successions,according to previous studies, have been referredto the first two substages of the lower Pleistocene,the Santernian and the Emilian.Pollen data from sixty-nine samples documentvegetation dynamics consisting of a temporalspread of three distinct forest formations: mixeddeciduousforest (with Quercus dominating),Juglandaceae forest (with Carya dominating)and mountain coniferous forest (with Piceadominating). Each forest formation formed avegetation belt, characterized by distinct temperatureand precipitation conditions. The spreadof the mixed deciduous forest indicates that thetemperature increases whereas the humidity islow. The transition to a Juglandaceae forest indicatesthe increase of humidity; this phase ischaracterized by “optimum” of temperature andprecipitations. The spread of mountain coniferousforest points out temperature drop and humiditystill high. When forest dynamics is interruptedby the spread of open vegetation, indicatingdecrease of humidity, a complete vegetationcycle occurs. Such cycle suggests that temperatureand humidity independently vary, withminimum and maximum of temperature generallypreceding humidity extremes. Each vegetationcycle, therefore, reveals the response ofvegetation to cyclic climatic changes occurringduring the early Pleistocene (glacial/interglacialcycles).Comparison with coeval pollen series fromother Italian sites shows wider spread of Piceaand minor expansion of open vegetation inNorthern Italy with respect to Central andSouthern Italy, suggesting the hypothesis ofmore humid conditions at the North (as alsodocumented by previous works). Taxodium pollen-typeis continuously represented in the Lamonepollen record, exhibiting values of 7% onaverage excluding Pinus ( 4% including pine).Sciadopitys shows a discontinuous presence andvery low percentages. Local and peculiar climateconditions may have favoured the long survivalof these taxa into the Pleistocene.On the basis of a comparison between the profileof Picea + Tsuga pollen curve (recorded atLamone) and the δ 18 O signal established at Site607 (North Atlantic), the vegetation cyclesdocumented in the Lamone valley have beententatively correlated to oxygen isotope stagesfrom 64 to 46. Stages 59 and 51 seem to be partiallyrecorded, whereas, stages 58, 57, 50 and49 are not recorded.2008040589俄 罗 斯 堪 察 加 古 近 纪 沉 积 磁 性 地 层 学 = Magnetostratigraphyof Paleogene deposits in Kamchatka.( 英 文 ). Minyuk P S; Gladenkov Yu B.Stratigraphy and Geological Correlation, 2007,15(1): 100-111Paleomagnetic characteristics of several Paleogenesections in Kamchatka (Il’pinskii Peninsula,Bering Island, Chemurnaut Bay, MametchaBay) are considered. The sections are correlatedwith due account for biostratigraphic data, andpossible correlation of magnetic polarity zonesdistinguished in the sections with the internationalmagnetostratigraphic scale is presented.2008040590较 干 旱 早 - 中 全 新 世 气 候 对 亚 马 孙 陆 森 林 的 影响 = Impact of a drier Early–Mid-Holocene climateupon Amazonian forests. ( 英 文 ). Mayle FE; Power M J. Philosophical Transactions of theRoyal Society B: Biological Sciences, 2008,363(1498): 1829-1838This paper uses a palaeoecological approachto examine the impact of drier climatic conditionsof the Early–Mid-Holocene (ca 8000–4000years ago) upon Amazonia's forests and their fireregimes. Palaeovegetation (pollen data) and palaeofire(charcoal) records are synthesized from20 sites within the present tropical forest biome,and the underlying causes of any emergent patternsor changes are explored by reference toindependent palaeoclimate data and present-daypatterns of precipitation, forest cover and fireactivity across Amazonia. During the Early–Mid-Holocene, Andean cloud forest taxa werereplaced by lowland tree taxa as the cloud baserose while lowland ecotonal areas, which arepresently covered by evergreen rainforest, wereinstead dominated by savannahs and/or semideciduousdry forests. Elsewhere in the AmazonBasin there is considerable spatial and temporalvariation in patterns of vegetation disturbanceand fire, which probably reflects the complexheterogeneous patterns in precipitation and seasonalityacross the basin, and the interactionsbetween climate change, drought- and fire susceptibilityof the forests, and Palaeo-Indian landuse. Our analysis shows that the forest biome inmost parts of Amazonia appears to have beenremarkably resilient to climatic conditions significantlydrier than those of today, despitewidespread evidence of forest burning. Only in178