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idea that, in a general sense, allogromiids areless tolerant of oxygen depletion than the calcareoustaxa that usually dominate foraminiferalfaunas in low-oxygen habitats. Organic-walledallogromiids occupy a variety of microhabitats.Intertidal and sublittoral species have been describedfrom the sheltered interiors of emptypolychaete tubes and large foraminiferal tests.Some species are associated with the sedimentwaterinterface while others occur at differentdepths within the sediment. Very elongate,thread-like morphotypes often live several centimetersbelow the sediment surface in bathyaland abyssal settings. The ecological role of organic-walledallogromiids is poorly known. Ingeneral, they seem to be less responsive to inputsof fresh organic matter than calcareous foraminifera.Indirect evidence suggests that manydeep-sea species, particularly forms with twoterminal apertures, consume bacteria.2008040222西 欧 亚 大 陆 极 区 陆 架 有 孔 虫 组 合 中 的Allogromiids = Allogromiids in foraminiferalassemblages on the western Eurasian arctic shelf.( 英 文 ). Sergei Korsun. Journal of ForaminiferalResearch, 2002, 32(4): 400-413Allogromiids sensu lato, including the ordersAllogromiida and Astrorhizida, are a commonlyignored group of marine benthos. Allogromiidstanding crop was examined in 121 sedimentsamples from the Barents and Kara seas. In 44 ofthese samples, foraminiferal biomass was determinedby calculation of cytoplasmic volume.Foraminiferal standing crop is dominated bysmall allogromiids in two types of stressed marginalenvironments—river-influenced shallowsand glacially fed fjords. Allogromiid frequencyalso increases in oligotrophic depressions of theopen shelf. Large astrorhizids such as Rhabdamminaabyssorum, Pelosina variabilis andHyperammina subnodosa, being common onfine-grained sediments which dominate the shelf,constitute biomasses of ca 3 mg/10cm3, exceedingby an order of magnitude the biomass of allother foraminifera combined. Foraminiferalbiomass values are comparable to those of macrofaunain shelf depressions distant from land,thus suggesting that, at least in food-deficientareas, the allogromiid foraminifera are a keygroup in benthic energy flux.2008040223沉 积 物 和 有 孔 虫 的 相 互 作 用 - 食 物 降 解 和 生物 扰 动 过 程 = Sediment interactions of foraminifera:implications for food degradationand bioturbation processes. ( 英 文 ). Onno Groß.Journal of Foraminiferal Research, 2002, 32(4):414-424 4 图 版 .Despite their small size, foraminifera oftenreach high standing stocks and play a significantrole in structuring the top layers of the sediment.However, the behavioral and ecological interactionsof foraminifera with the surrounding sedimentshave been rarely investigated. In order tostudy these poorly known aspects of foraminiferalecology, living foraminifera from bathyaland shallower water depths were successfullymaintained in microcosms and their relationshipwith the sediment was investigated. Sedimentinteractionsof foraminifera take part mainly as aresult of 1) locomotion, 2) deposit feeding withingestion and egestion within different sedimentlayers, thus causing constant bioturbation, and 3)the use of particles for the formation of cysts forfeeding, reproduction, chamber building or protection.Movement by foraminifera results in theventilation of the sea floor as demonstrated bythe active and passive transport of luminescentparticles. From the experiment conducted, a highmixing rate (Db 0.2cm 2/day) for the foraminiferalassemblage was calculated. Thus, benthicforaminifera contribute significantly to the bioturbationof surface sediments. These observationsare discussed in relation to microhabitatsand the fate of organic matter at and below thesediment-water interface.2008040224网 足 虫 有 孔 虫 的 自 动 重 组 = Autonomous reorganizationof foraminiferan Reticulopodia. ( 英文 ). Travis J L; Welnhofer E A. Journal of ForaminiferalResearch, 2002, 32(4): 425-433 2 图版 .Reticulopodia, the diagnostic cytoplasmicappendage of the foraminifera, are complex networksof branched and anastomosed pseudopodia.The instantaneous patterns of these networksare highly variable and are remodeled almostcontinuously. Real-time light microscopic observationsdemonstrate that these morphogeneticprocesses occur autonomously throughout theentire networks, even at their farthest reacheswhich may be located at great distances from thecell body. Portions of reticulopodia severed fromthe cell body undergo autonomous and stereotypedmorphological rearrangements to formsatellites, which are a relatively large cytoplasmicmass located centrally within a radiatingpseudopodial network. Pseudopodial movementsand structural rearrangements are active energyrequiringprocesses that depend on intracellularfactors such as the formation and reorganizationof microtubule cytoskeletal elements. Here weshow that that reticulopodia consistently assumea spiral shape when placed on a cationic substrate,indicating that the pseudopodial pattern isalso influenced by environmental factors such asinteractions with the substratum. Our studies71