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Island, Papua New Guinea. ( 英 文 ). Lentfer C;Torrence R. Review of Palaeobotany and Palynology,2007, 143(3-4): 83-105An integrated approach to the reconstructionof vegetation history and human land use duringthe Holocene on Garua Island, Papua NewGuinea analysed sediments and plant microfossils(phytoliths and starch granules) togetherwith archaeological data. The long-term recordis punctuated by a series of volcanic disasters,where repeated cycles of massive destructionwere followed by differing cycles of forest regeneration.The plant microfossil record showsthat instead of long-term forest recovery, theoverall pattern of regeneration was progressivelymore disrupted. Through time regeneration washalted earlier in the sequence and then revertedto increasingly open plant communities dominatedby grasses. The temporal patterns of burning,stone artefact discard, and plant introductionsdemonstrate that the increased impact ofhuman systems of land management was primarilyresponsible for the temporal patterning. Mostnotably, the study shows that human interferencebegins much earlier than expected given previousarchaeological research and relatively intensiveburning and landscape modification, possiblyindicating cultivation, predates the introductionof Lapita pottery.2008040030捷 克 内 陆 盆 地 凝 灰 岩 层 中 保 存 的 威 斯 特 法 阶- 下 斯 蒂 芬 阶 泥 沼 群 落 的 植 被 模 式 = Vegetationpatterns of Westphalian and Lower Stephanianmire assemblages preserved in tuff beds ofthe continental basins of Czech Republic. ( 英 文 ).Opluštil S; Pšenička J; Libertín M; Šimůnek Z.Review of Palaeobotany and Palynology, 2007,143(3-4): 107-154Several volcanoclastic beds in coal-bearingstrata of the Late Palaeozoic continental basinsin the Czech Republic contain in situ buriedpeat-forming plant ecosystems the study ofwhich provides a unique insight into their structuralpattern and species composition. MiddlePennsylvanian peat-forming plant assemblagesat 14 localities in basins of central and westernBohemia and from the Intra-Sudetic Basin (NEBohemia) were characterised based on collectionsof plants preserved in five successive tuffbeds: the tuff of the 3rd Žd'árky Coal (Duckmantian),the Whetstone Horizon in the roof ofthe Lower Radnice Coal (Bolsovian), the Velkáopuka intercalated in the Upper Radnice Coal(Bolsovian), the Z-tuff capping the Lower LubnáCoal (Bolsovian), and the tuff of the ChotíkovCoal (Westphalian D/Cantabrian). Analysis ofplant remains preserved in these beds reveals theco-existence of several ecologically controlledplant assemblages ranging from structurallysimple, low-diversity to high-diversity phytocoenoses,with complex structural patterns andsynecological relationships. Most of these assemblagesrepresent variations of the basic lepidodendrid-dominatingforest with co-dominanceor sub-dominance of other basic plant groups.This pattern is comparable to the forests of theparalic basins located in coastal settings. An assemblagedominated by the sub-arborescent lycopsidOmphalophloios feistmantelii (Feistmantel)comb. nov. was recognised in the UpperRadnice Coal. Only a few assemblages are poorin lycopsids. These are mostly mixed fern–calamites or pteridosperm-dominated phytocoenoses.The assemblages described represent variousstages of hydroseral succession. The initial stageconsists of a low-diversity fern–calamitesdominatedassemblage of 5 species, not higherthen 1–1.5 m which re-colonised the previouslydrowned mire. The climax stage of the successionis represented by high-diversity lepidodendridforests with well-developed ground-coverand shrubs. The number of taxa of such assemblagesvaries between 20 and 30 species withinan area of about 100 m 2 .A comparison of the peat-forming flora withthe clastic substrate floras preserved in mudstonesor roof shales revealed substrate preferenceof individual species. Most of them grew inboth types of substrates; only a few wereadapted to only one type of substrate.2008040031奥 陶 纪 - 志 留 纪 界 线 附 近 多 种 危 机 时 期 的 生 物礁 : 加 拿 大 安 提 克 斯 提 岛 及 世 界 情 况 = Reefsduring the multiple crises towards the Ordovician-Silurianboundary: Anticosti Island, easternCanada, and worldwide. ( 英 文 ). Copper P. CanadianJournal of Earth Sciences, 2001, 38(2):153-171Multiple latest Ordovician (Rawtheyan–Hirnantian) glaciations in central Africa, withconcomitant global sea-level lowstands andcooler, restricted, equatorial carbonate shelvesand ramps, interrupted by warmer interstadialhighstands, had a dramatic global impact on thetropical shallow-water reef ecosystem and carbonateproduction. With the Ordovician-Silurianboundary strata on Anticosti Island as a globalstandard for a carbonate shelf-ramp setting, thelatest Ordovician and earliest Silurian revealthree reef phases, ended by three extinctions.The first extinction, towards the end of the Rawtheyan,affected the last "Richmondian"-typereefs (Vaureal Formation, Mill Bay Member).The second extinction was less pronounced, endingwith reefs at the base of the Prinsta Member(Ellis Bay Formation), interpreted as the top ofthe Normalograptus extraordinarius graptolite10