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mated depositional interval of 10 to 100 KA andthus potentially preserves community patterns inecological and short-term evolutionary time.The community is dominated by epibenthicvagile deposit feeders and sessile suspensionfeeders, represented primarily by arthropods andsponges. Most species are characterized by lowabundance and short stratigraphic range andusually do not recur through the section. It islikely that these are stenotopic forms (i.e., tolerantof a narrow range of habitats, or having anarrow geographical distribution). The few recurrentspecies tend to be numerically abundantand may represent eurytopic organisms (i.e.,tolerant of a wide range of habitats, or having awide geographical distribution). Rarefactioncurves demonstrate variation in species richnessthrough the GPB and suggest that morestenotopic species could still be discovered withadditional sampling. Comparisons between richnessand evenness trends suggest that the communityis relatively stable overall, despite gradualspecies turnover through time, especially inassemblages from younger beds. Less diverseassemblages with low species evenness possiblyrepresent the onset of less favourable environmentalconditions.Fossil occurrences in individual beds wereanalysed using a range of statistical techniques(Correspondence Analysis, Canonical CorrespondenceAnalysis, Minimum Spanning Tree,Indicator Species Analysis, Mantel Test) to extractcommunity patterns. Results suggest thepresence of four fossil assemblages based ondistinct species associations. The different assemblagespresumably reflect variations in environmentaland ecological conditions, some actingthrough time, leading to species turnover.“Disturbances” (e.g., changes in paleo-redoxconditions), differences in substrate firmness,and limited taphonomic biases are probably themain factors contributing to community structure.The influence of ecological factors, however, isalso predicted from non-random patterns of speciesrecurrences in successive events. Preliminarycomparisons with Lower Cambrian Chengjiang-typeassemblages of southern China suggestthat the overall structure and ecology ofCambrian communities remained relatively stableuntil at least the Middle Cambrian in subtidalsiliciclastic soft substrate environments.Comparisons with modern marine benthicecosystems further suggest the Burgess Shalecommunity was probably highly dependent onimmigration from a regional pool of species aftereach burial event. This could support the viewthat species availability, habitat characteristics,and recolonisation processes were more importantin structuring the community in the longtermthan species interactions or environmentalvariations at a local scale.2008040041古 生 态 学 在 预 测 山 区 未 来 变 化 中 的 作 用 = Arole for palaeoecology in anticipating futurechange in mountain regions?. ( 英 文 ). Gosling WD; Bunting M J. Palaeogeography PalaeoclimatologyPalaeoecology, 2008, 259(1): 1-52008040042晚 泥 盆 世 法 门 晚 期 和 早 石 炭 世 杜 内 早 期 的 环境 变 化 : 来 自 南 欧 稳 定 同 位 素 和 牙 形 类 生 物相 的 启 示 = Environmental change during theLate Famennian and Early Tournaisian (LateDevonian-Early Carboniferous): implicationsfrom stable isotopes and conodont biofacies insouthern Europe. ( 英 文 ). Kaiser S I; Steuber T;Becker R T. Geological Journal, 2008, 43(2-3):241 - 260A biostratigraphic correlation of the Devonian/Carboniferous(D/C) boundary sectionsfrom the Carnic Alps, the Graz Palaeozoic, theMontagne Noire and the Pyrenees resulted in ahigh-resolution record of the carbon isotopiccomposition of micrites ( 13 C carb ), of sedimentaryorganic matter ( 13 C org ) and of oxygen isotoperatios of conodont apatite ( 18 O phosph ). The studiesfocused on the interval between the Upper posteraZone (Late Famennian) and the sandbergiZone (Lower Tournaisian). For the first time,weak but significant positive carbon isotope excursionsin micrites and in the sedimentary organicmatter is reported from the Middle andUpper expansa zones of the Carnic Alps. Theycoincide with a decrease in the oxygen isotopevalues of conodont apatite. The excursions indicatechanges in the global carbon cycle duringan episode of high seawater temperatures, andcorrelate with sedimentary change and a stepwiseeustatic rise in the Rhenish Massif. Highcarbon isotope values were also measured inlimestones from the Graz Palaeozoic in the Upperpraesulcata Zone, which were previouslyreported from the Rhenish Massif, Carnic Alps,Montagne Noire and the North America continent.The change from a palmatolepidpolygnathidconodont biofacies to a palmatolepid-bispathodid-branmehlidbiofacies in theexpansa Zone in the Carnic Alps is obviouslyinfluenced by anoxic conditions and repeatedtransgressive phases. The protognathodids andthe polygnathids start to radiate in the Upperpraesulcata Zone, after the main end-Famennianextinction episode. This is connected with thedisappearance of the palmatolepids, and environmentalstress created by worldwide anoxicconditions, climate change and sea-level changes,stimulated the radiation of both protognathodids14