Total organic carbon, lithology and alkylthiophenes in immature sediments (Table 1)

A series of novel long-chain 3,4-dialkylthiophenes (C36-C54) was identified in a number of sediments ranging from Pleistocene to Cretaceous. The identifications were based on mass spectral characterisation, desulphurisation and mass spectral data of synthesised model compounds. These organic sulphur compounds are probably formed by sulphur incorporation into mid-chain dimethylalkadienes with two methylenic double bonds. These putative precursor lipids are unprecedented and may be considered rather unusual. The distribution of 3,4-dialkylthiophenes in sediments varies considerably with the depositional palaeoenvironment, indicating that these compounds have a potential as molecular markers reflecting changes in palaeoenvironment.

Reefs shift from net accretion to net erosion along a natural environmental gradient

Coral reefs persist in an accretion-erosion balance and ocean acidification resulting from anthropogenic CO2 emissions threatens to shift this balance in favor of net reef erosion. Corals and calcifying algae, largely responsible for reef accretion, are vulnerable to environmental changes associated with ocean acidification, but the direct effects of lower pH on reef erosion has received less attention, particularly in the context of known drivers of bioerosion and natural variability. This study examines the balance between reef accretion and erosion along a well-characterized natural environmental gradient in Kane'ohe Bay, Hawai'i using experimental blocks of coral skeleton. Comparing before and after micro-computed tomography (µCT) scans to quantify net accretion and erosion, we show that, at the small spatial scale of this study (tens of meters), pH was a better predictor of the accretion-erosion balance than environmental drivers suggested by prior studies, including resource availability, temperature, distance from shore, or depth. In addition, this study highlights the fine-scale variation of pH in coastal systems and the importance of microhabitat variation for reef accretion and erosion processes. We demonstrate significant changes in both the mean and variance of pH on the order of meters, providing a local perspective on global increases in pCO2. Our findings suggest that increases in reef erosion, combined with expected decreases in calcification, will accelerate the shift of coral reefs to an erosion-dominated system in a high-CO2 world. This shift will make reefs increasingly susceptible to storm damage and sea-level rise, threatening the maintenance of the ecosystem services that coral reefs provide.

Lithofacies, chronostratigraphy, minerals and diagenetic silica facies at DSDP Leg 80 Holes

X-ray powder diffraction and optical and scanning-electron microscope analyses of sediment samples taken from four sites drilled in the Goban Spur area of the northeast Atlantic show variable diagenetic silicification of sediments at several stratigraphic horizons. The results are as follows: 1. The silicified sediments are middle Eocene at Site 548, Paleocene to lower Albian at Site 549, upper to lower Paleocene at Site 550, and lower Turanian at Site 551. 2. There are three types of these silicified sediments: nodular type in carbonate-rich host sediments, bedded type in clayey host sediments, and a type transitional between the other two. 3. Silica diagenesis is considered to progress as follows: dissolution of siliceous fossils; precipitation of opal CT in pore spaces and transformation of biogenic silica (opal A) to opal CT, development of opal CT cement; chalcedonic quartz precipitation in pore spaces and replacement of foraminiferal tests by chalcedonic quartz; and finally, transformation of opal CT to quartz, and cementation. But the strong influence of host-sediment types on diagenetic silica fades is recognized. Bedded-type silicified sediments in a clayey environment indicate a lower grade of silica diagenesis. Only very weak chalcedonic quartz formation is recognized, and there is no opal CT cementation, even in Lower Cretaceous bedded-type clayey silicified sediments. 4. The rf(101) spacing of opal CT shows two distinct trends of ordering or decrease with burial depth; one is a rapid change, in the case of nodular silicified sediments, and the other is a more gentle shift, found in bedded silicified sediments. 5. Diagenetic silica facies of the nodular type develop as irregular concentric zones around some nodule nuclei. Also, quartz-chert nodule formation occurs at rather shallower horizons, and is discordant with the trend of decreasing d(101) spacing in opal CT. 6. Silicified sediments at Site 551 are shallower than at the other sites. The diagenetic silica facies suggest the probable erosion of 300 m or more of sediment at this site. 7. The zeolites clinoptilolite and phillipsite were found in the sediment samples recovered on Leg 80. Clinoptilolite occurs from the shallower levels to the deepest horizons of diagenetically silicified zones, suggesting that clinoptilolite formation is related to diagenesis of biogenic silica. Phillipsite at Site 551 (Section 551-5-2) may originate from volcanogenie material.

Stable isotope analysis of Porites coral core EILAT-1

The environmental interpretation of the 13C/12C variations in the skeletons of massive corals is still a matter of debate. A 19-year seasonal skeletal 13C/12C record of a shallow-water Pontes coral from the northern Red Sea (Gulf of Aqaba) documents interannual events of extraordinarily large plankton blooms, indicated by anomalous 13C depletions in the coral skeleton. These blooms are caused by deep vertical water mass mixing, convectively driven in colder winters, which results in increased supplies of nutrients to the surface waters. The deep vertical mixings can sometimes be driven by the cooling occurring throughout the Middle East after large tropical volcanic eruptions. We therefore have evidence in our coral skeletal 13C/12C record for an indirect volcanic signal of the eruptions of El Chichón (1982) and Mount Pinatubo (1991). Deep mixing induced 13C/12C variations of the dissolved inorganic carbon in the surface waters can be neglected at this location. We therefore suggest that the 13C skeletal depletions can be best explained by changes in the coral's autotrophy-heterotrophy diet, through increased heterotrophic feeding on Zooplankton during the blooms. Increased feeding on 13C-depleted Zooplankton or increased heterotrophy at the expense of autotrophy can both result in a 13C-depleted coral skeleton. However, this suggestion requires more testing. If our conclusions are substantiated, seasonal skeletal 13C/12C records of corals which change from autotrophy under normal conditions to increased heterotrophy during bloom events may be used as indicators of ocean paleoproductivity at interannual resolution, available from no other source.

The impact of ocean acidification and warming on the skeletal mechanical properties of the sea urchin Paracentrotus lividus from laboratory and field observations

Increased atmospheric CO2 concentration is leading to changes in the carbonate chemistry and the temperature of the ocean. The impact of these processes on marine organisms will depend on their ability to cope with those changes, particularly the maintenance of calcium carbonate structures. Both a laboratory experiment (long-term exposure to decreased pH and increased temperature) and collections of individuals from natural environments characterized by low pH levels (individuals from intertidal pools and around a CO2 seep) were here coupled to comprehensively study the impact of near-future conditions of pH and temperature on the mechanical properties of the skeleton of the euechinoid sea urchin Paracentrotus lividus. To assess skeletal mechanical properties, we characterized the fracture force, Young's modulus, second moment of area, material nanohardness, and specific Young's modulus of sea urchin test plates. None of these parameters were significantly affected by low pH and/or increased temperature in the laboratory experiment and by low pH only in the individuals chronically exposed to lowered pH from the CO2 seeps. In tidal pools, the fracture force was higher and the Young's modulus lower in ambital plates of individuals from the rock pool characterized by the largest pH variations but also a dominance of calcifying algae, which might explain some of the variation. Thus, decreases of pH to levels expected for 2100 did not directly alter the mechanical properties of the test of P. lividus. Since the maintenance of test integrity is a question of survival for sea urchins and since weakened tests would increase the sea urchins' risk of predation, our findings indicate that the decreasing seawater pH and increasing seawater temperature expected for the end of the century should not represent an immediate threat to sea urchins vulnerability

'Serán ceniza, más tendrá sentido', los manuscritos de Campo de Sangre

La obra de Aub viene marcada por el sello de lo laberíntico, de its mundo interior obsesivo y multiforme que se express cuando y como pudo o le dejaron. No es por ello de extrañar que la elaboración de sus obras completes y la revision de sus papeles personales nos regale un sinfin de descubrimientos gratificantes. En mi trabajo como editor de Campo de sangre, en el rococo de las Obras completas del autor publicadas por la Biblioteca Valenciana, el hallazgo riles notable es el de los diversos cuadernos (quince, por ahora) que incluyen el esqueleto de la novela y sus primeros apuntes. El primer objetivo de este trabajo es intentar reconstruir el proceso genetico de la novela a partir de dicho material autógrafo, estableciendo unas hipótesis que el articulista sabe provisionales pero que pretender dar cuenta de un giro radical del autor entre su primera concepción de Campo de sangre y su redacción definitive. En segundo lugar, aunque de rnanera paralela, se pretende hacer que la labor mencionada contribuya a esclarecer la figura de Aub como creador y como hombre, en la medida en que dichas facetas seas separables.

'Serán ceniza, más tendrá sentido', los manuscritos de Campo de Sangre

La obra de Aub viene marcada por el sello de lo laberíntico, de its mundo interior obsesivo y multiforme que se express cuando y como pudo o le dejaron. No es por ello de extrañar que la elaboración de sus obras completes y la revision de sus papeles personales nos regale un sinfin de descubrimientos gratificantes. En mi trabajo como editor de Campo de sangre, en el rococo de las Obras completas del autor publicadas por la Biblioteca Valenciana, el hallazgo riles notable es el de los diversos cuadernos (quince, por ahora) que incluyen el esqueleto de la novela y sus primeros apuntes. El primer objetivo de este trabajo es intentar reconstruir el proceso genetico de la novela a partir de dicho material autógrafo, estableciendo unas hipótesis que el articulista sabe provisionales pero que pretender dar cuenta de un giro radical del autor entre su primera concepción de Campo de sangre y su redacción definitive. En segundo lugar, aunque de rnanera paralela, se pretende hacer que la labor mencionada contribuya a esclarecer la figura de Aub como creador y como hombre, en la medida en que dichas facetas seas separables.

Abundances and contents of major silicoflagellates from IODP Holes of Exp302

The silicoflagellate taxa obtained in IODP Expedition 302 (ACEX) were identified and counted in order to establish the silicoflagellate biostratigraphy in the central Arctic Ocean. These microfossils in the ACEX samples were preserved in the Lithology Units 1/6 and 2, which are dark silty clay and biosiliceous ooze, respectively. The silicoflagellate skeletons in the ACEX samples are assigned to 56 taxa. Seven taxa were described as new species, which were abundant in Lithology Unit 2. Comparison with several study cases outside the Eocene Arctic Ocean suggested that the silicoflagellate assemblages in ACEX were unique in Lithology Unit 2. The dominance of silicoflagellate taxa varied throughout the lithological section. Based on the cluster analysis by Morishita similarity index C(Lambda), the silicoflagellate assemblageswere divided into nine assemblage groups. The silicoflagellate datum event of the first occurrence of Corbisema hexacantha in the lower part of Lithology Unit 1/6 is regarded. Based on the datum events for silicoflagellate and palynomorphs, the assigned epoch of Lithology Units 1/6 and 2 is the middle Eocene.

'Serán ceniza, más tendrá sentido', los manuscritos de Campo de Sangre

La obra de Aub viene marcada por el sello de lo laberíntico, de its mundo interior obsesivo y multiforme que se express cuando y como pudo o le dejaron. No es por ello de extrañar que la elaboración de sus obras completes y la revision de sus papeles personales nos regale un sinfin de descubrimientos gratificantes. En mi trabajo como editor de Campo de sangre, en el rococo de las Obras completas del autor publicadas por la Biblioteca Valenciana, el hallazgo riles notable es el de los diversos cuadernos (quince, por ahora) que incluyen el esqueleto de la novela y sus primeros apuntes. El primer objetivo de este trabajo es intentar reconstruir el proceso genetico de la novela a partir de dicho material autógrafo, estableciendo unas hipótesis que el articulista sabe provisionales pero que pretender dar cuenta de un giro radical del autor entre su primera concepción de Campo de sangre y su redacción definitive. En segundo lugar, aunque de rnanera paralela, se pretende hacer que la labor mencionada contribuya a esclarecer la figura de Aub como creador y como hombre, en la medida en que dichas facetas seas separables.

Growth rates and skeletal density of the scleractinian cold-water coral Desmophyllum dianthus at Isla Liliguapi (Fjord Comau, southern Chile)

It has been hypothesized that endolithic photo-autotrophs inside the skeleton of cold-water corals may have a mutualistic relationship with the coral host positively affecting coral calcification. This study investigated the effect of endolithic photo-autotrophs on the apical septal extension of the cold-water coral Desmophyllum dianthus at Fjord Comau, southern Chile (42.41° - 42.15°S, 72.5°W). The fluorescent staining agent calcein was used to document the linear apical extension of septae for a period of one and a half years between 2006 and 2007. The results showed a severe reduction in extension rates associated with the presence of endolithic photo-autotrophs. Infested individuals grew about half as fast as non-infested polyps with a median value of 1.18 µm/day compared to 2.76 µm/day. Contrary to the initial hypothesis, these results point toward a parasitic relationship between D. dianthus and its endolithic photo-autotrophs potentially impairing coral fitness. However, further data on physiological parameters and other aspects of the calcification process are necessary to confirm these findings.

Documentation, profile descriptions and analytical results of loes profiles from Bavaria, southern Germany

This study investigates the landscape evolution and soil development in the loess area near Regensburg between approximately 6000-2000 yr BP (radiocarbon years), Eastern Bavaria. The focus is on the question how man and climate influenced landscape evolution and what their relative significance was. The theoretical background concerning the factors that controlled prehistoric soil erosion in Middle Europe is summarized with respect to rainfall intensity and distribution, pedogenesis, Pleistocene relief, and prehistoric farming. Colluvial deposits , flood loams, and soils were studied at ten different and representative sites that served as archives of their respective palaeoenvironments. Geomorphological, sedimentological, and pedological methods were applied. According to the findings presented here, there was a high asynchronity of landscape evolution in the investigation area, which was due to prehistoric land-use patterns. Prehistoric land use and settlement caused highly difIerenciated phases of morphodynamic activity and stability in time and space. These are documented at the single catenas ofeach site. In general, Pleistocene relief was substantially lowered. At the same time smaller landforms such as dells and minor asymmetric valleys filled up and strongly transformed. However, there were short phases at many sites, forming short lived linear erosion features ('Runsen'), resulting from exceptional rainfalls. These forms are results of single events without showing regional trends. Generally, the onset of the sedimentation of colluvial deposits took place much earlier (usually 3500 yr BP (radiocarbon) and younger) than the formation of flood loams. Thus, the deposition of flood loams in the Kleine Laaber river valley started mainly as a consequence of iron age farming only at around 2500 yr BP (radiocarbon). A cascade system explains the different ages of colluvial deposits and flood loams: as a result of prehistoric land use, dells and other minor Pleistocene landforms were filled with colluvial sediments. After the filling of these primary sediment traps , eroded material was transported into flood plains, thus forming flood loams. But at the moment we cannot quantify the extent ofprehistoric soil erosion in the investigation area. The three factors that controlled the prehistoric Iandscapc evolution in the Ioess area near Regensburg are as follows: 1. The transformation from a natural to a prehistoric cultural landscape was the most important factor: A landscape with stable relief was changed into a highly morphodynamic one with soil erosion as the dominant process of this change. 2. The sediment traps of the pre-anthropogenic relief determined where the material originated from soil erosion was deposited: either sedimentation took place on the slopes or the filled sediment traps of the slopes rendered flood loam formation possible. Climatic influence of any importance can only be documented as the result of land use in connection with singular and/or statistic events of heavy rainfalls. Without human impact, no significant change in the Holocene landscape would have been possible.