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以 松 柏 类 和 盾 籽 类 为 优 势 的 低 分 异 度 、 季 节性 热 带 景 观 : 新 墨 西 哥 早 二 叠 世 Abo 组 = Alow diversity, seasonal tropical landscape dominatedby conifers and peltasperms: Early PermianAbo Formation, New Mexico. ( 英 文 ). Di-Michele W A; Chaney D S; Nelson W J; LucasS G; Looy C V; Quick K; Wang Jun. Review ofPalaeobotany and Palynology, 2007, 145(3-4):249-273Walchian conifers (Walchia piniformis Sternberg,1825) and peltasperms similar to Supaiathinnfeldioides White and cf. Supaia anomalaWhite dominate floodplain deposits of a narrowstratigraphic interval of the middle Abo Formation,Lower Permian of central New Mexico.The plant fossils occur in thinly bedded units upto two meters thick, consisting of coarse siltstoneto very fine sandstone with clay partings.Bedding is primarily tabular, thin, and bears rareripple marks and trough cross beds. Beddingsurfaces display mud cracks, raindrop imprints,horizontal and vertical burrows of invertebrates,and footprints of terrestrial vertebrates. Thesefeatures indicate intermittent and generally unchannelizedstream flow, with repeated exposureto air. Channels appear to have cannibalized oneanother on a slowly subsiding coastal plain.Conifers are dominant at three collecting sitesand at three others Supaia dominates. Althougheach of these genera occurs in assemblagesdominated by the other, there are no truly codominantassemblages. This pattern suggestsalternative explanations. Landscapes could haveconsisted of a small-scale vegetational patchworkdominated almost monospecifically in anyone patch, meaning that these plants could havecoexisted across the landscape. On the otherhand, conifer and supaioid dominance couldhave been temporally distinct, occurring duringdifferent episodes of sedimentation; although inthe field there are no noticeable sedimentologicaldifferences between conifer-dominated andSupaia-dominated channel deposits, they mayrepresent slightly different climatic regimes. Theconsiderable morphological differences betweenconifers and Supaia suggest that the floristicpatterns are not a taphonomic effect of the lossof a significant part of the original biodiversity.In general, the climate under which this vegetationdeveloped appears to have been relativelywarm and arid, based on the geology (pervasivered color [oxidation], calcrete in paleosols, andabundant mud cracks evidencing ephemeral flowin streams) and biology (low floristic diversity,xeromorphic plant physiognomies).2008040025冰 岛 中 中 新 世 植 物 群 — 一 个 岛 屿 上 的 早 期 植被 ? = Middle Miocene floras of Iceland — theearly colonization of an island?. ( 英 文 ).Grímsson Friðgeir; Denk T; Símonarson L A.Review of Palaeobotany and Palynology, 2007,144(3-4): 181-219Two macrofloras, 15 and 13.5 Ma old, are describedfrom the oldest exposed plant bearingsediments on Iceland. Many of the taxa are mentionedfor the first time and a lime tree, Tiliaselardalense, is described as a new species.In case of the older flora, differences in theenvironment are reflected in plants derived fromvolcanic sediments from high elevations (Selárdalur,15 Ma) and from lowland alluvial plains(Botn, 15 Ma). The former are characterized byzonal elements and dominated by Fagus. Thelatter is dominated by conifers inhabitingswamps and hummocks. The younger Ketilseyriflora (13.5 Ma) is poorer and more similar to theSelárdalur flora. Both floras suggest a humidwarm temperate climate (mostly Cfa climatesensu Köppen) with a number of exotic elements(Glyptostrobus, Sequoia, Magnolia, Cercidiphyllum).Evaluating the dispersal mechanisms of allthe taxa shows that at least some (Aesculus,Fagus) could not have possibly colonized Icelandcrossing large ocean barriers. Furthermore,most anemochorous taxa recorded have a verylimited dispersal radius. This suggests that when“proto-Iceland” was colonized, it was connectedto the mainland or accessible via a chain of islands.This land could have been part of theGreenland–Scotland Transverse Ridge that isbelieved to have persisted from the early Cenozoicto Late Oligocene and partly into the MiddleMiocene.2008040026晚 二 叠 世 热 带 地 区 古 代 野 火 的 证 据 — 来 自 约旦 Um Irna 组 的 炭 化 木 化 石 = Evidence forpalaeo-wildfire in the Late Permian palaeotropics– charcoalified wood from the Um Irna Formationof Jordan. ( 英 文 ). Uhl D; Hamad A A;Kerp H; Bandel K. Review of Palaeobotany andPalynology, 2007, 144(3-4): 221-230Charcoalified wood from the lower part of theLate Permian Um Irna Formation of Jordan isdescribed. This charcoal represents the first evidenceof palaeo-wildfire during the Late Permianin northern Gondwana. The source localityat the northeastern rim of the Dead Sea hasyielded excellently preserved gymnosperm charcoal.Taxonomically most remains are identifiedas Dadoxylon-type gymnosperm wood. However,one woody specimen exhibits features that suggesta potential taxonomic relationship to theCorystospermales, a group otherwise representedat this locality by compressed fronds assigned tothe genus Dicroidium. The occurrence of charcoalin the Um Irna Formation is in accordancewith sedimentological data, as well as palaeo-8