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schackoinids, indicating that the environmentremained ecologically unstable. The end of‘large form eclipse’ marks the base of Phase V.During Phase V (118 kyr), planktonic foraminiferalabundance and diversity return to valuescomparable to those of Phase I, showing thegradual recovery of the ecosystem. However,high numbers of hedbergellids and heterohelicidssuggest that the environmental perturbationrelated to the Bonarelli Event did not end duringthis phase, but continued well beyond depositionof the organic-rich layers. Our analysis showsthat, in deep-water settings, the severe paleoenvironmentalperturbation induced by the BonarelliEvent led to assemblages dominated by thesmall-sized, opportunistic hedbergellids andschackoinids. At the same time, the small-sizedand presumably low-oxygen-tolerant, opportunisticheterohelicids underwent a marked decline.This scenario may be related to the exceptionallyhigh-nutrient and low-oxygen content of theseawater, but also to variation of other ecologicalparameters. The perforate, elongated chambersand tubulospines of schackoinids may representthe best survivorship tool to haveachieved better oxygen and nutrient uptake. Weinfer that schackoinids are useful indicators forextremely stressed environments in low- to middle-latitude,open-marine, deep-water settingsduring the Late Cretaceous.2008040161晚 白 垩 世 河 口 高 分 辨 率 海 平 面 变 化 循 环 ——利 用 胶 结 有 孔 虫 对 变 化 幅 度 范 围 的 研 究 =High-resolution estuarine sea level cycles fromthe late Cretaceous: amplitude constraints usingagglutinated foraminifera. ( 英 文 ). Tibert N E;Leckie R M. Journal of Foraminiferal Research,2004, 34(2): 130-143 2 图 版 .Agglutinated foraminifera provide highresolutionproxies for relative sea level change inLate Cretaceous coal-bearing strata. Three foraminiferalassemblages are recognized whereTrochammina (trochospiral) occurs in abundancewith either one of the following: 1)Miliammina (quinqueloculine) associated withcarbonaceous shale, interpreted as the marsh; 2)Ammobaculites (uncoiled) and estuarine ostracodesassociated with shelly mudstones, interpretedas the central, muddy estuary; and 3)Verneulinoides and Textularia (serial) associatedwith gray mudstones, interpreted as distal estuary(open bay). The marsh represents 0–1m waterdepth and this approximates absolute meansea level, the central estuary represents 5–8mwater depth, and the distal estuary (open bay)represents water depths of 10m or greater. Alternationsbetween foraminiferal associations in a25-m section of the upper middle TuronianSmoky Hollow Member, Straight Cliffs Formation,indicate sea level amplitude changes thatranged from 1–10 meters.2008040162理 查 德 岛 西 北 北 极 喀 斯 特 湖 的 有 壳 变 形 有 孔虫 类 的 特 征 = The characteristics of Thecamoebiansof Arctic Thermokarst lakes, Richards island,N.W.T.. ( 英 文 ). Dallimore A. Journal ofForaminiferal Research, 2004, 34(4): 249-257 2图 版 .Thecamoebian species and assemblages reportedfrom various limnological environmentsin North America are not appreciably differentacross a climatic gradient ranging from semitropicalto Arctic latitudes. However, certainmorphological characteristics of individual speciesreferred to as "strains" do appear to be verysensitive to changing environmental conditions.Thus, the identification of strains is a usefultechnique in the interpretation of paleoenvironmentalconditions. Other features considereddiagnostic of Arctic conditions in particular, areassemblages dominated by one or two species,and large and coarse tests. Some thecamoebianspecimens found in lakes on Richards Island,Northwest Territories, Canada, are two to threetimes larger than those reported from temperatelocations. These "giant" specimens are perhapsrelated to very short periods of warm water temperatureswhich appear to be favorable for reproduction.Tests grow to a large size after extendedfeeding periods during the short Arcticsummers. For the first time, continuous annuallake temperature data confirm the hypothesisthat the presence of abundant large tests in anassemblage may be indicative of cold climates,due to a short reproductive season.2008040163瑞 典 一 个 低 氧 海 湾 200 年 的 环 境 记 录 —— 来自 底 栖 有 孔 虫 、 沉 积 特 征 和 水 文 资 料 的 解 释= A 200-year environmental record of a lowoxygenfjord, Sweden, elucidated by benthicforaminifera, sediment characteristics and hydrographicdata. ( 英 文 ). Filipsson H L; NordbergK. Journal of Foraminiferal Research,2004, 34(4): 277-293In this study, we have detailed the benthic environmentof a sill fjord on the Swedish westcoast, which is characterized by brackish conditions,intermittent water exchanges, and periodiclow oxygen. We have used three importanttools—benthic foraminifera, sediment characteristics,and historical records of hydrographicdata. Periods of low oxygen have resulted insequences of laminated sediments in the fjord.The foraminiferal fauna present in the fjord is oflow diversity and low abundance, mostly Elphidiumspecies—an assemblage that has domi-50