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2008040208大 堡 礁 区 域 绿 岛 礁 的 底 栖 有 孔 虫Calcarinidae 科 = Benthic foraminifera of thefamily Calcarinidae from Green Island reef,greatbarrier reef province. ( 英 文 ). Lobegeier M K.Journal of Foraminiferal Research, 2002, 32(3):201-216 2 图 版 .The genera of calcarinids Calcarina andBaculogypsina are the dominant foraminifera inthe surface sediment of Green Island Reef of theGreat Barrier Reef Province, northeastern Australia.Two species of Calcarina are recognized:C. spengleri (Gmelin) and C. mayori Cushman.Both species are common and widely distributedon the Great Barrier Reef and in the Indo-Pacificregion but have been much confused in the literature.They are re-evaluated in this contribution.Hansen (1980) described and illustrated aneo-type of C. spengleri which is different inappearance to the lecto-type illustration ofGmelin, 1791. The neotype is inseparable fromC. hispida Brady, 1884 and therefore the namespengleri has priority over hispida. Calcarinaspengleri (Gmelin) is the dominant species atGreen Island and is common in shallow water onthe reef flat. Calcarina mayori Cushman, asmaller less hispid species, is subordinate to C.spengleri and dominates in deeper water off thereef flat. This species has commonly been reportedas C. spengleri or C. hispida. The monotypicgenus Baculogypsina, represented byBaculogypsina sphaerulata Parker & Jones, doesnot dominate in any region but is a shallow waterhigh-energy species on Green Island Reef.These species are common and abundant epiphyteson a variety of reef top macroalgae, especiallythe reef-rim restricted algal turf. Due totheir preference for shallow water, high-energyenvironments most calcarinid specimens sufferappreciable test surface degradation soon afterdeath due to physical abrasion, breakage andbioerosion. Four taphonomic groups characterizedby the preservation of Calcarina specimensare identified by cluster analysis of samples.Samples of groups 1 and 4, in which most Calcarinaspecimens are broken and abraded, characterizethe reef flat where sediment reworkingby biological agencies involving callianassidshrimp and endolith activity are dominant, aswell as physical processes of degradation. Group2 samples are composed primarily of Calcarinaspines and occur in the leeward shoals. Sedimentgrains in this area have a long surface residencetime and are little affected by waves and currentagitation. Spines are considered to represent themost resistant of Calcarina fragments. Group 3samples contain the best preserved Calcarina atGreen Island Reef and are located in the windwardshoals. A high production rate applies inthis zone but the tests have suffered significantimpact damage indicating that physical processesdominate degradation. Group 4 samplestypify shallow water samples close to the reefflat where physical energy plays a significantrole in these areas and therefore has a high degreeof abrasion and breakage. The distributionof all three calcarinid species is limited to thewestern Indo-Pacific. Despite the occurrence ofC. spengleri around India, these calcarinids areotherwise absent from the Indian Ocean and alsoabsent east of 170°W. They are shallow watertropical species and are particularly abundant oncoral reef flats.2008040209冰 岛 北 部 陆 架 和 斜 坡 上 底 栖 有 孔 虫 的 现 代 分布 = Modern distribution of benthic foraminiferaon the north icelandic shelf and slope. ( 英 文 ).Rytter F; Knudsen K L; Seidenkrantz M S;Eiríksson J. Journal of Foraminiferal Research,2002, 32(3): 217-244Forty-six surface samples from the north Icelandicshelf and slope were analyzed with respectto both living (stained) and total (living/stained+ dead/unstained) benthic foraminiferalfaunas. Near-coastal samples are stronglydominated by species indicating a high-energyenvironment, among these various species of thegenus Cibicides. Nonionellina labradorica,which has a strong affinity to areas of high surfaceprimary production, is constrained to oceanicboundaries on the outer shelf. Faunistically,the area is further divided into eastern and westernparts, the submarine Kolbeinsey Ridge forminga barrier. Calcareous species, particularlyMelonis barleeanus, prevail in the western part,while the assemblages in the eastern part arestrongly dominated by agglutinated foraminifera.Principal Component Analyses (PCA) help distinguishfour main components of both the total(living + dead) assemblage (TA) and the totalliving assemblage (TLA), as well as of the total(living + dead) calcareous assemblage (CA) andthe living calcareous assemblage (CLA). Thecomponents of the TA and TLA are similar, themajor differences being controlled by speciesdependentvariables such as adaptability tochanges in food supply and, in the eastern part ofthe area, depth of microhabitat and possibly alimited primary production. The PCA analysesof the calcareous species alone (CA and CLA)define components with significant differencesin the foraminiferal population. The calcareousdistribution in particular is important in applicationof modern distribution patterns to paleoceanographicaland paleoclimatological reconstructionsin areas where post-mortem disintegrationof the agglutinated fauna may have occurred.66