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arctic environment over this critical interval andfor which such sections are few.2008040255西 太 平 洋 有 孔 虫 Nummulitidae 的 评 述 = Remarkson west Pacific Nummulitidae (foraminifera).( 英 文 ). Hohenegger J; Yordanova E. Journalof Foraminiferal Research, 2000, 30(1): 3-28 5 图 版 .Living Nummulitidae achieve their highestdiversity in the subtropical and tropical WestPacific. Although all house symbiotic microalgae,they avoid highly illuminated areas near thewater surface, since their flat tests could be easilydamaged by the hydrodynamic regime. Thepreference for calm water conditions extendstheir depth distribution down to the base of thephotic zone. West Pacific Nummulitidae can bedifferentiated into ten species belonging to sixgenera according to an ecological species concept.The genus Operculina d’Orbigny is representedby three species. While O. discoidalis(d’Orbigny) prefers a fine-grained bottom undermedium light conditions (10% surface intensity),O. ammonoides (Gronovius) prefers a coarsersubstrate and sometimes can be found on hardbottoms. Light dependence ranges from 1.5% to68% surface intensity. Less illuminated coarsesands are inhabited by Operculina cf. O. complanata(Defrance), which is the dominant symbiont-bearingforaminifer between light intensitiesof 0.2% to 12% surface illumination. Thegenus Planostegina Banner and Hodgkinsondemonstrates transitions to the genus Operculinain test form and surface, while the division intochamberlets is similar to Heterostegina.Planostegina operculinoides (Hofker) is distinguishedby flat tests and delicate chamberlets. Itlives on sandy bottoms restricted to light intensitiesbetween 0.45% and 26% surface illumination.The more robust Planstegina aff. P. operculinoides(Hofker) prefers light intensities between0.4% and 2.7% surface illumination.Planoperculina heterosteginoides (Hofker)shows morphological transition to Operculina cf.O. complanata in developing incomplete septula.This species lives in low illuminated areas (0.3%to 2.5% surface intensity) and prefers medium tofine-grained sands. Heterostegina depressad’Orbigny spans a broad range in light intensities(2% to 70% surface illumination), and isprotected against irradiation by thick tests and acryptic life mode near the surface. Test constructionenables life under strong hydrodynamic regimes.This species lives firmly attached to hardsubstrates, thus counteracting transportation bywater movement. Nummulites venosus (Fichteland Moll) differs from H. depressa in havingundivided chambers. It lives exclusively oncoarse sand and avoids high sediment movement,thus starting its distribution beneath the fairweather wave base. According to light intensities,the upper limit may be similar to O. ammonoides(80%), while the lower limit is 2.5% surface illumination.Operculinella cumingii (Carpenter)inhabits coarse to medium sand in deeper regionsbetween 1.2% and 25% surface illumination.Tests of the cyclic, large-sized speciesCycloclypeus carpenteri Brady are easily transporteddue to the thin, plate-like form. The upperdistribution limit correlates with the storm wavebase, restricting C. carpenteri to depths below50 m. The lower distribution limit depends onlight intensity and is located near the base of thephotic zone (0.4% surface illumination).2008040256红 海 亚 喀 巴 湾 埃 拉 特 市 北 部 海 湾 网 笼 养 鱼 场对 底 栖 有 孔 虫 分 布 的 影 响 = Impact of a netcage fish farm on the distribution of benthic foraminiferain the northern Gulf of Eilat (Aqaba,Red Sea). ( 英 文 ). Angel D L; Verghese S. Journalof Foraminiferal Research, 2000, 30(1): 54-65Two sediment transects, at 23m depth, weresampled below a commercial fish farm at thenorthern end of the Gulf of Eilat in order to describethe benthic foraminiferal communityalong an organic enrichment gradient. Sedimentorganic matter, porewater ammonia and phosphateconcentrations reflected the input from theoverlying fish cages and there was generally adecrease in these variables with distance fromthe point source. Rose-bengal stained foraminiferawere found at all of the stations sampled belowthe fish farm, i.e. there were no azoic sediments.Fifty-one species of foraminifera (>45µm) were found in the sediments around the fishfarm but most were rare species. The most abundant(generally > 83% of the foraminifer abundance)species (stained + unstained) found wereAmphisorus hemprichii, Amphistegina lessonii,Assilina ammonoides, Borelis schlumbergeri,Challengerella bradyi, Hauerina diversa, andPeneroplis planatus. Five of these foraminiferaare algal symbiont bearing forms. The diatombearingspecies, A. lessonii and A. ammonoides,constituted 40 to 50% of the total number oftests. The most abundant stained species were A.ammonoides, B. schlumbergeri, H. diversa and P.planatus. Abundances of foraminifera werehighest in the "hypertrophic" zone, adjacent tothe fish cages. The most abundant speciesshowed negative correlations between totalabundance of tests and organic matter in the uppercentimeter of the sediment. Negative correlationswere also found between abundances ofboth total and stained tests of the most abundantspecies and integrated ammonia concentrations.No clear indicator species of the organically-82