Communities and microhabitats of living benthic foraminifera from the tropical East Atlantic

Living (Rose Bengal stained) benthic foraminifera were collected with a multicorer from six stations between 2°N and 12°S off West Africa. The foraminiferal communities in the investigated area reflect the direct influence of different productivity regimes, and are characterized by spatially and seasonally varying upwelling activity. At five stations, foraminiferal abundance coincides well with the gradient of surface productivity. However, at one station off the Congo River, the influence of strong fresh water discharge is documented. Although this station lies directly in the center of an upwelling area, foraminiferal standing stocks are surprisingly low. It is suggested that the Congo discharge may induce a fractionation of the organic matter into small and light particles of low nutritional content, by contrast to the relatively fast-sinking aggregates found in the centers of high productivity areas. Quality and quantity of the organic matter seem to influence the distribution of microhabitats as well. The flux of organic carbon to the sea-floor controls the sequence of degradation of organic matter in sediment and the position of different redox fronts. The vertical foraminiferal stratification within sediment closely parallels the distribution of oxygen and nitrate in porewater, and reflects different nutritive strategies and adaptation to different types of organic matter. The epifauna and shallow infauna colonize oxygenated sediments where labile organic matter is available. The intermediate infauna (M. barleeanum) is linked to the zone of nitrate reduction in sediments where epifaunal and shallow infaunal species are not competitive anymore, and must feed on bacterial biomass or on metabolizable nutritious particles produced by bacterial degradation of more refractory organic matter. The deep infauna shows its maximum distribution in anoxic sediments, where no easily metabolizable organic matter is available.

Elementa geometriae planae ac solidae, nec non selecta ex Archimede theoremata /

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Andreae Tacquet Societatis Iesu Trigonometria plana /

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Christophori Clavii Bambergensis e Societate Iesv Opervm mathematicorvm tomvs primvs[-qvintvs]...

Vol. 1 contains In Euclidem commentarius only. The rest of v. 1 is bound at the end of v. 2. Refutatio Cyclometriae Iosephi Scaligeri is bound in v. 5.

Distribution of Upper Cretaceous deep water agglutinated foraminifera in sediments of the North Atlantic and its marginal seas (Tab. 1)

The stratigraphic and biogeographic distribution of more than 170 species of deep-water agglutinated benthic foraminifers (DWAF) from the North Atlantic and adjacent marginal seas has been compared with paleoenvironmental data (e.g. paleobathymetry, oxygenation of the bottom waters, amount of terrigenous input and substrate disturbance). Six general types of assemblages, in which deep water agglutinated taxa occur, are defined from the Turonian to Maastrichtian times: 1. High latitude slope assemblages 2. Low to mid latitude slope assemblages 3. Flysch-type assemblages 4. Deep water limestone assemblages (,,Scaglia,,-type) 5. Abyssal mixed calcareous-agglutinated assemblages 6. Abyssal purely agglutinated assemblages Latitudinal differences in faunal composition are observed, the most important of which is the lack or extreme paucity of calcareous forms in high latitude assemblages. East-to-west differences appear to be of comparatively minor importance. Most DWAF species occur in all studied regions and are thus considered as cosmopolitan. Biostratigraphic turnovers in the taxonomic content of assemblages are observed in the lowermost Turonian, mid-Campanian and in the upper Maastrichtian to lowermost Paleocene. These datum levels correspond to inter-regional and time-constant paleooceanographic events, which probably also affected the deep-water benthic biota. This allows us to use deep-water agglutinated foraminifers for biostratigraphy in the North Atlantic sequences deposited below CCD and to geographically extend the currently used zonal schemes which have been established in the Carpathian and Alpine areas.

Occurence of monothalamous foraminifera in Admiralty Bay, King George Island, West Antarctica (Table 1, 2)

During the late 2007 austral summer, 20 sediment samples were collected in Admiralty Bay (King George Island, South Shetlands, West Antarctica) from 8 down to 254 m water-depth (mwd). The samples yielded abundant assemblage of monothalamous benthic foraminifera, belonging to at least 40 morphospecies. They constituted the first such collection from Antarctic Peninsula fjords and provided a new insight into this group's diversity and distribution. Among organic-walled taxa, Psammophaga sp., Allogromia cf. crystallifera, and three morphotypes of Gloiogullmia were especially abundant. Agglutinated forms were dominated by Hippocrepinella hirudinea, Psammosphaera spp., Lagenammina spp., and various mudballs. Although, the majority of the morphotypes were known from other high?latitude locations, somewere reported for the first time. Our quantitative data (>125 µm) showed the greatest differences between monothalamous foraminifera assemblages at shallowest water depths above 50 mwd. The deepest assemblages from between 179 and 254 mwd, were most similar, suggesting uniform near-bottom conditions at ~200 mwd throughout the Admiralty Bay.

Micropaleontological investigation of sediment core Kronsmoor

Benthic foraminiferal and calcareous nannofossil assemblages, as well as stable isotope data from the Campanian/Maastrichtian boundary interval (~71.4 to ~70.7 Ma) of the Kronsmoor section (North German Basin), were investigated in order to characterize changes in surface-water productivity and oxygen content at the seafloor and their link to climatic and paleoceanographic changes. A nutrient index based on calcareous nannofossils is derived for the high-latitude, epicontinental North German Basin, reflecting changes in surface-water productivity. Oxygen isotopes of well-preserved planktic foraminiferal specimens of Heterohelix globulosa reflect warmer surface-water temperatures in the lower part of the studied succession and a cooling of up to 2°C (0.5 per mil) in the upper part (after 71.1 Ma). For the lower and warmer part of the investigated succession, benthic foraminiferal assemblages and the calcareous nannofossils indicate well-oxygenated bottom waters and low-surface water productivity. In contrast, the upper part of the succession is characterized by cooler conditions, lower oxygen content at the seafloor and increasing surface-water productivity. It is proposed that the cooling phase starting at 71.1 Ma was accompanied by increasing surface-water mixing caused by westerly winds. As a consequence of mixing, nutrients were advected from sub-surface waters into the mixed layer, resulting in increased surface-water productivity and enhanced organic matter flux to the seafloor. We hypothesize that global sea-level fall during the earliest Maastrichtian (~71.3 Ma), indicated by decreasing carbon isotope values, may have led to a weaker water mass exchange through narrower gateways between the Boreal Realm and the open North Atlantic and Tethys oceans. Both the weaker water mass exchange and enhanced surface-water productivity may have led to slightly less ventilated bottom waters of the upper part of the studied section. Our micro-paleontological and stable isotopic approach indicates short-term (<100 kyr) changes in oxygen consumption at the seafloor and surface-water productivity across the homogeneous Boreal White Chalk succession of the North German Basin.

Distribution of microorganisms in recent sediments of Kiel Bay

Die angewandte Mikropaläontologie bestimmt heute im wesentlichen das Alter eines Gesteins mit Hilfe von Faunenvergesellschaftungen. Aus der Zusammensetzung der Fauna, aus dem Einsatz oder Fehlen bestimmter Gattungen und Arten, aus den Mineralien, die das Gestein aufbauen, aus dem ganzen Bild, das eine aus einem Gestein herausgeschlämmte Fauna dem Bearbeiter gibt, läßt sich das Alter dieses Gesteins festlegen. Will man aber verschiedene Bohrungen, vor allem auch räumlich weit voneinander getrennter Gebiete, miteinander parallelisieren, so liegt das Kernproblem der Mikropaläontologie in der Frage, ob es sich bei verschiedenen Faunen tatsächlich um Alters- oder nur um Faziesunterschiede handelt. Da die Grundlagen der mikropaläontologischen Arbeitsweise zum weitaus größten Teil auf den Ergebnissen von Untersuchungen fossiler Faunen beruhen, müssen zu ihrer Unterbauung Untersuchungen an recentem Material folgen. Besonders spielt das Ineinandergreifen mariner und brackischer Sedimente in der angewandten Mikropaläontologie eine große Rolle. Auf Grund der Tatsache, daß ein großer Teil von Gattungen und Arten der Foraminiferen an der Wende Kreide/Tertiär ausstirbt und neue an ihre Stelle treten, stellt Glässner (1948) die Behauptung auf, daß die aktualistisch gewonnenen Ergebnisse für vortertiäre Faunen nur eine geringe Bedeutung besitzen. Auch seien vortertiäre, brackische Foraminiferen nicht bekannt (Glässner 1948, S. 191). Hiltermann (1948) konnte aber bereits im nordwestdeutschen Malm brackische, d. h. in Brackwasser eindringende Foraminiferen nachweisen. Auf jeden Fall behalten aktualistische Unterlagen ihren Wert für das Tertiär und Quartär. Die Faunen, die in recenten, brackischen Sedimenten nebeneinander auftreten, sind in einem Bohrprofil in einem Gestein übereinander zu erwarten. Gelingt es, die Beziehungen einer recenten Fauna zu ihrer Umwelt zu klären, dann können umgekehrt aus fossilen, ihnen gleichen oder ähnlichen Faunen Rückschlüsse auf die Entstehungsbedingungen von Gesteinen gezogen werden. Unter Umständen können der Verlauf einer Transgression, Küstennähe, die Höhe des Salzgehaltes des Meerwassers, die vorherrschenden Temperaturen u. a., aus ihnen abgelesen werden. Die Ostsee ist ein klassisches Brackwassergebiet der Erde. Ihr westlicher Teil, die Kieler Bucht, wurde erst in jüngster geologischer Zeit vom Meer überflutet. Nach Tapfer (1940) begann hier die flandrische Transgression erst etwa um 7500 v. d. Zw. mit dem Erreichen des heutigen Meeresniveaus. Seit dieser Zeit erst entstehen neue Küstenformen, wird der Meeresboden umgelagert und bilden sich marine und brackische Absätze in diesem Gebiet.

Recent benthic foraminifera of the Scotia Sea and Argentine Basin

We investigated 88 surface sediment samples taken with a multiple corer from the southwestern South Atlantic Ocean for their live (Rose Bengal stained) and dead benthic foraminiferal content. Using Q-Mode Principal Component Analysis six live and six dead associations are differentiated. Live and dead association distributions correspond fairly well; differences are mainly caused by downslope transport and selective test destruction. In addition, four potential fossil associations are calculated from the dead data set after removal of non-fossilizable species. These potential fossil associations are expected to be useful for paleoceanographic reconstructions. Environments are described in detail for the live and potential fossil associations and for selected species. Along the upper Argentine continental slope strong bottom currents control the occurrence of live, dead and potential fossil Angulogerina angulosa associations. Here, particles of a high organic carbon flux rate remain suspended. Below this high energy environment live, dead and potential fossil Uvigerina peregrina dominated associations correlate with enhanced sediment organic carbon content and still high organic carbon flux rates. The live A. angulosa and U. peregrina associations correlate with high standing crops. Furthermore, live and dead Epistominella exigua-Nuttallides umbonifer associations were separated. Dominance of a Nuttallides umbonifer potential fossil association relates to coverage by Antarctic Bottom Water (AABW) and Lower Circumpolar Deep Water (LCDW), above the Calcite Compensation Depth (CCD). Three associations of mainly agglutinated foraminifera occur in sediments bathed mainly by AABW or CDW. A Reophax difflugiformis association was found in mud-rich and diatomaceous sediments. Below the CCD, a Psammosphaera fusca association occurs in coarse sediments poor in organic carbon while a Cribrostomoides subglobosus-Ammobaculites agglutinans association covers a more variable environmental range with mud contents exceeding 30%. One single Eggerella bradyi-Martinottiella communis association poor in both species and individuals remains from the agglutinated associations below the CCD if only preservable species are considered for calculation.

FUNGOS ASSOCIADOS ÀS SEMENTES DE Enterolobium contortisiliquum : ANÁLISE DA INCIDÊNCIA, CONTROLE E EFEITOS NA QUALIDADE FISIOLÓGICA COM O USO DE EXTRATOS VEGETAIS

Os fungos são os principais micro-organismos associados às sementes, podendo causar danos, tanto na fase de campo, como também na pós-colheita e durante o armazenamento. Nesta última fase, a deterioração pode ocorrer pela ação específica de fungos, afetando a qualidade fisiológica das sementes. A utilização de extratos de plantas com propriedades antimicrobianas são alternativas ecológicas e promissoras para substituir a proteção promovida pela aplicação de fungicidas. Objetivou-se nesta pesquisa avaliar a eficiência dos extratos de Allamanda blanchetti e Momordica charantia nas concentrações de 10, 100, 500 e 1000 ppm sobre a micoflora e germinação em sementes de Enterolobium contortisiliquum . As sementes foram coletadas em diferentes municípios do estado da Paraíba (Areia, Arara, Conde e Sobrado). Os lotes foram submetidos a testes de sanidade e de germinação. A avaliação da incidência de fungos foi feita a partir da visualização dos fungos através do método de papel de filtro. Utilizaram-se no teste de sanidade 100 sementes por tratamento, as quais foram imersas em 20 mL dos extratos por cinco minutos, em seguida incubadas em placas de Petri sobre dupla camada de papel de filtro. No teste de germinação utilizaram-se 200 sementes, distribuídas em papel germitest e germinadas à temperatura de 30 ± 2°C. O delineamento experimental utilizado foi o inteiramente casualizado. Constatou-se nas sementes de Enterolobium contortisiliquum os fungos: Aspergillus niger , Aspergillus flavus , Rhizopus stolonifer , Penicillium sp., Curvularia lunata , Nigrospora sp. e Cladosporium sp. Os extratos de Allamanda blanchetti e Momordica charantia nas concentrações de 500 e 1000 ppm causaram redução da frequência dos fungos. O extrato de Momordica charantia nas concentrações de 500 e 1000 ppm proporcionou o aumento na germinação e primeira contagem, além de reduzir o percentual de sementes mortas.

Fungal endophytic communities associated to the phyllosphere of grapevine cultivars under different types of management

Fungal endophytes present in different asymptomatic grapevine plants (Vitis vinifera L.) located in different vineyards within Alentejo, a highly important viticulture region in Portugal, were identified in this study. Sampled grapevine plants included the three most representative cultivars in the region, Syrah, Cabernet Sauvignon, and Aragonez, growing under two different modes of management, conventional and biological. Sixteen fungal taxa were identified through sequencing of the internal transcribed spacer region. Total number of endophytic fungi isolated showed significant differences both in management mode and in cultivars, with higher numbers in grapevines under conventional mode and from Syrah cultivar. The composition of fungal endophytic communities did not show significant differences among cultivars, but differences were observed between fungal communities isolated from grapevines under biological or conventional modes. The most fungal taxa isolated from grapevines cultivated under biological mode were Alternaria alternata, Cladosporium sp., and Nigrospora oryzae, and under conventional mode Botrytis cinerea, Epicoccum nigrum, and Epicoccum sp. These differences suggest that the different products used in grapevine production have impacts in fungal endophytic composition. Further investigation of the identified fungi with respect to their antagonistic characteristics and potential use in plant protection to ensure food safety is now in course.