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nificant variations in the degree of loss of theorganic-cemented agglutinants were observeddown core. This group is preserved down to 5–10 cm at the shallow OMZ sites and down togreater depths at well-aerated and oligotrophicsites. The lower rate of disintegration of theseforms, in the deeper locations of the Red Sea,may be related to low microbial activity. Thisresults in the preservation of increasing numbersof organic-cemented shells down-core.2008040233关 于 底 栖 有 孔 虫 生 物 量 与 有 机 炭 通 量 的 关 系= On the coherence of organic carbon flux andbenthic forminiferal biomass. ( 英 文 ). AltenbachA V; Struck U. Journal of Foraminiferal Research,2001, 31(2): 79-85Benthic foraminiferal biomass values from theliterature are compared with annual flux rates oforganic carbon to the sea floor. A data set of 212locations is compiled from 2m to 9300m waterdepth, covering the Arctic, Atlantic, Indian, andPacific Oceans. Annual flux rates nearly cover 3orders of magnitude (0.3g to >100g Corg m–2),and foraminiferal biomass covers more than 5orders of magnitude (0.01 mg to >4g Corg m–2).In shallow waters no coherence is observed dueto randomly distributed biomass values spanning4 orders of magnitude. Flux rates and biomassvalues are correlated (r = 0.7, p < 0.001) at waterdepth below 1000m, but within a broad range ofvariability (about factor 4 from the regressionline). Annual fluctuations of foraminiferal biomassvalues are reported by several authorswithin a factor of 5 to more than 10, corroboratingthese ranges of variability as natural. In addition,broad deviations were observed to resultfrom methodological errors or spatial gradients.In the deep sea, annual flux rates of organic carbonrange from 0.3 to 5g m–2. The gradient inmean foraminiferal biomass (Corg) is steeper,decreasing from 0.002 to 0.3g m–2. A decreaseof annual flux rates by a factor of about 10 producesa decrease in mean foraminiferal biomassby a factor of more than 100. As a result, thepotential nutritional supply per biomass unit orindividual is gradually improved by up to a factorof 10 for most oligotrophic environments.This may be considered an adaptation to loweredefficiency of food gathering and increasingamounts of biodegraded matter. From the calculationspresented, an annual turnover of foraminiferalbiomass can be estimated within 1 to2 years.2008040234底 栖 有 孔 虫 和 孔 隙 水 氧 含 量 -- 西 伊 比 利 亚 边缘 种 的 边 界 条 件 的 重 新 审 视 = Benthic foraminiferaand pore-water oxygen profiles: a reassessmentof species boundary conditions at thewestern Iberian Margin. ( 英 文 ). Joachim Schönfeld.Journal of Foraminiferal Research, 2001,31(2): 86-107The depth distribution of living (Rose Bengalstained)benthic foraminifera in near-surfacesediments was analyzed along 4 short cores fromthe western Iberian Margin and Gulf of Cadiz atwater depths from 800 to 1920 m. Pore-wateroxygen, Chloroplastic Pigment Equivalent(CPE), and total organic carbon (Corg) concentrationswere measured in the same or adjacentcores. These values were used to constrain thelimiting oxygen and nutrient levels that definedthe ranges in sediment depth and abundancemaxima of foraminiferal species. The populationdensity showed a good correlation with porewateroxygenation indicating that oxygen is alimiting factor for endobenthic foraminiferalassemblages at mid-depths between 800 and1200m. At the deep-water site, however, thefauna appeared nutrient limited. More than halfof the benthic species occupied extended sedimentdepth habitats and a wide range of oxygenlevels among the sites studied. Thirty-nine of103 species occurred in two or more cores andshowed distinct abundance maxima, 36 in theuppermost 2.0 cm where the CPE concentrationswere high. Living foraminifers were not found atdepths where the CPE-values were lower than0.1 µg/g. This level indicates trophic conditionscritical for the survival of endobenthic species.The frequency distribution of the lower oxygenrange limits of all species showed maxima at thehigh oxic/low oxic (3 ml/l), low oxic/suboxic(1.5 ml/l), and suboxic/dysoxic (0.3 ml/l)boundaries and thus depicted the ecological significanceof these previously recognized ecolimits.Only 30 % of the species display consistentpatterns in relation to pore water oxygen. Dysoxicindicators were Globobulimina affinis,Chilostomella ovoidea and Bathysiphon capillare.Many species previously designated assuboxic indicators were ubiquitous or preferredmicrohabitats at oxic levels. Boundary conditionsfor the dysoxic indicator G. affinis werepelagic flux rates higher than 3.5g C m–2 yr–1, ahabitat depth below the homogeneously bioturbatedlayer in areas outside of high productivityzones, and CPE concentrations of 0.1 to 1.0,preferentially 0.7 to 0.8 µg/g. The distributionpattern suggested that G. affinis thrives mainlyon dysoxic bacteria and actively seeks this nutrientresource.2008040235加 拿 大 马 尼 托 巴 Winnipegosis 湖 北 部 非 海 相有 孔 虫 Cribroelphidium gunteri 的 发 现 =Non-marine occurrence of the foraminifer Cribroelphidiumgunteri in northern lake Winnipegosis,Manitoba, Canada. ( 英 文 ). Boudreau R E;75