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nated the foraminiferal fauna for at least 170years. During this time period, however, therehave been events when normal marine specieshave been introduced, or foraminiferal abundanceand faunal diversity have suddenly increased.These events are linked to short sequencesof homogenous sediments within thelaminated sequences that, in turn, suggest moreoxic conditions. Since the late 1940s, we have amore-or-less continuous salinity record from thefjord, the product of an instrumental monitoringprogram. This record has been used, togetherwith the foraminiferal distribution and sedimentcharacteristics, to reconstruct the salinity variationsthat occurred prior to the instrumentalmonitoring program. The salinity in the fjord hasalternated between periods of low salinity (26–28.5%), which correspond with non-laminatedsediments, and periods of higher salinity(>28.5%), corresponding with laminated sequences.Despite a general low abundance offoraminiferal fauna, there was a significantlyhigher diversity during deposition of laminatedsequences than non-laminated sequences. In thedeepest part of the record, corresponding to thelate eighteenth and early nineteenth century, adifferent fauna occurs, where species in additionto Elphidium occur, suggesting generally highersalinities (29–31).2008040164加 拿 大 北 极 区 Cape Phillips 组 Wenlock 统 上部 的 放 射 虫 Ceratoikiscidae 科 = UpperWenlock Ceratoikiscidae (Radiolaria) from theCape Phillips Formation, Arctic Canada. ( 英 文 ).Noble P J; Lenz A C. Journal of Paleontology,2007, 81(5): 1044-1052 6 图 版 .Taxa belonging to the Ceratoikiscidae are describedin detail from two measured sections ofMember C of the Cape Phillips Formation exposedalong Rookery Creek, Cornwallis Island,Arctic Canada. The sections encompass uppermostSheinwoodian (top lower Wenlock) to thebase of the Gorstian (base Ludlow) and are datedby graptolites assigned to the Cyrtograptusperneri–Monograptus opimus Zone (upperSheinwoodian), the Cyrtograptus lundgreniZone (lower Homerian), and the Colonograptuspraedeubeli–Colonograptus deubeli Zone (upperHomerian). Radiolarians are found in greatabundance throughout the lower Homerian, allowingfor the establishment of the first appearanceof the genus Helenifore Ormiston andNazarov. Helenifore is emended to accommodatethe Silurian species H. quadrispina n. sp.and H. speciosus (Furutani 1990). One new genus,Kappaforma, including the new species, K.insecta, is described, as is the new species H.quadrispina. Ceratoikiscum octapleura Renzand C. armiger Furutani are synonymized withC. lenoides Renz, and H. planus Umeda is synonymizedwith H. speciosus.2008040165天 堂 的 麻 烦 ?1953 年 和 2005 年 西 印 度 群 岛特 立 尼 达 岛 东 部 近 岸 Ibis Field 地 区 海 底 底 栖有 孔 虫 组 合 的 比 较 = Trouble in Paradise? Acomparison of 1953 and 2005 benthonic foraminiferalseafloor assemblages at the Ibis Field,offshore eastern Trinidad, West Indies. ( 英 文 ).Wilson B. Journal of Micropalaeontology, 2006,25(part 2): 157-164Foraminiferal communities are not static, butchange in response to environmental perturbations.Given sufficient time, the change will berecorded in the total (live+dead) seafloor assemblage,from which valuable information regardingenvironmental trends can be obtained by resamplingassemblages at the decadal scale.The seafloor assemblage in the 5km x 6kmIbis Field, off southeast Trinidad, first surveyedin 1953, was re-examined in 2005. The faunahad changed markedly between the surveys.Overall increases in the proportional abundancesof Uvigerina subperegrina, Ammonia pauciloculatal,Rolhauseniarolhauseni and Pseudononionattanticum indicate an increase in nutrient supplythat apparently killed off Cibicidoides pseudoungerianusand Miliolinella subrotunda, andreduced the relative abundance of Hanzawaiaconcentrica, but did not affect the relative abundanceof Cancris sagrai. As shown by similar1953 and 2005 planktonic/benthonic foraminiferalratios, the increased nutrient supply impactedon both surface and bottom waters.Of the six most abundant species in 2005, fiveshowed the same general biogeographical distributionswithin the field in 1953 and 2005. However,whereas the proportional abundance ofUvigerina subperegrina in 1953 increasedsouthwards, in 2005 it increased northwards.Trinidad cannot be the source for the nutrientenrichment: the island lies down-current fromthe Ibis Field. Sources must therefore be soughtup-current and to the southeast, in the Amazon,Essequibo and Orinoco river basins, or along theSouth American shoreline. It is speculated thatthe nutrient enrichment may be a consequence ofincreased phytoplankton primary productionassociated with nitrogen-rich run-off from SouthAmerican sugarcane plantations, or from flushingof organic carbon from poorly regulatedsewage systems or shrimp farms in South America.2008040166实 验 室 条 件 下 测 得 的 深 海 底 栖 有 孔 虫 的 呼 吸速 率 = Deep-sea benthic foraminiferal respirationrates measured under laboratory conditions.51