Zooplankton and seston in the White Sea and its chemical composition

A technique of zooplankton net sampling at night in the Kandalaksha and Dvinskii Bays and during the full tide in the Onezhskii Bay of the White Sea allowed us to obtain "clean" samples without considerable admixtures of terrigenous particulates. Absence of elements-indicators of the terrigenous particulates (Al, Ti, and Zr) in the EDX spectra allows to conclude that ash composition of tested samples is defined by constitutional elements comprising organic matter and integument (chitin, shells) of plankton organisms. A quantitative assessment of accumulation of ca. 40 chemical elements by zooplankton based on a complex of modern physical methods of analysis is presented. Values of the coefficient of the biological accumulation of the elements (Kb) calculated for organic matter and the enrichment factors (EF) relative to Clarke concentrations in shale are in general determined by mobility of the chemical elements in aqueous solution, which is confirmed by calculated chemical speciation of the elements in the inorganic subsystem of surface waters of Onezhskii Bay.

Hydrocarbons in surface layer bottom sediments from the North Dvina Riverand the southern part of the Dvina Bay, White Sea

Analysis of molecular composition of alkanes in bottom sediments of the southern part of Dvina Bay (White Sea) in October 2001 revealed the following main peculiarities of hydrocarbon behavior in the estuary: dominating of high molecular C23-C45 compounds and irregular distribution of hydrocarbons in bottom sediments as a result of high sedimentation rate and active hydrodynamics in the studied area.

Surface water properties, phytoplankton composition and photosynthesis rates of Amundsen Sea sites

The phytoplankton community composition and productivity in waters of the Amundsen Sea and surrounding sea ice zone were characterized with respect to iron (Fe) input from melting glaciers. High Fe input from glaciers such as the Pine Island Glacier, and the Dotson and Crosson ice shelves resulted in dense phytoplankton blooms in surface waters of Pine Island Bay, Pine Island Polynya, and Amundsen Polynya. Phytoplankton biomass distribution was the opposite of the distribution of dissolved Fe (DFe), confirming the uptake of glacial DFe in surface waters by phytoplankton. Phytoplankton biomass in the polynyas ranged from 0.6 to 14 µg Chl a / L, with lower biomass at glacier sites where strong upwelling of Modified Circumpolar Deep Water from beneath glacier tongues was observed. Phytoplankton blooms in the polynyas were dominated by the haptophyte Phaeocystis antarctica, whereas the phytoplankton community in the sea ice zone was a mix of P. antarctica and diatoms, resembling the species distribution in the Ross Sea. Water column productivity based on photosynthesis versus irradiance characteristics averaged 3.00 g C /m**2/d in polynya sites, which was approximately twice as high as in the sea ice zone. The highest water column productivity was observed in the Pine Island Polynya, where both thermally and salinity stratified waters resulted in a shallow surface mixed layer with high phytoplankton biomass. In contrast, new production based on NO3 uptake was similar between different polynya sites, where a deeper UML in the weakly, thermally stratified Pine Island Bay resulted in deeper NO3 removal, thereby offsetting the lower productivity at the surface. These are the first in situ observations that confirm satellite observations of high phytoplankton biomass and productivity in the Amundsen Sea. Moreover, the high phytoplankton productivity as a result of glacial input of DFe is the first evidence that melting glaciers have the potential to increase phytoplankton productivity and thereby CO2 uptake, resulting in a small negative feedback to anthropogenic CO2 emissions.

Sedimentaology, pollen profile, and climate reconstruction on a sediment core from Trou Lake, Yukon, Canada

Beringian climate and environmental history are poorly characterized at its easternmost edge. Lake sediments from the northern Yukon Territory have recorded sedimentation, vegetation, summer temperature and precipitation changes since ~16 cal ka BP. Herb-dominated tundra persisted until ~14.7 cal ka BP with mean July air temperatures less than or equal to 5 °C colder and annual precipitation 50 to 120 mm lower than today. Temperatures rapidly increased during the Bølling/Allerød interstadial towards modern conditions, favoring establishment of Betula-Salix shrub tundra. Pollen-inferred temperature reconstructions recorded a pronounced Younger Dryas stadial in east Beringia with a temperature drop of ~1.5 °C (~2.5 to 3.0 °C below modern conditions) and low net precipitation (90 to 170 mm) but show little evidence of an early Holocene thermal maximum in the pollen record. Sustained low net precipitation and increased evaporation during early Holocene warming suggest a moisture-limited spread of vegetation and an obscured summer temperature maximum. Northern Yukon Holocene moisture availability increased in response to a retreating Laurentide Ice Sheet, postglacial sea level rise, and decreasing summer insolation that in turn led to establishment of Alnus-Betula shrub tundra from ~5 cal ka BP until present, and conversion of a continental climate into a coastal-maritime climate near the Beaufort Sea.

A database of multi-year (2004-2010) quality-assured surface solar hourly irradiation measurements for the Egyptian territory

A database containing the global and diffuse components of the surface solar hourly irradiation measured from 1 January 2004 to 31 December 2010 at eight stations of the Egyptian Meteorological Authority is presented. For three of these sites (Cairo, Aswan, and El-Farafra), the direct component is also available. In addition, a series of meteorological variables including surface pressure, relative humidity, temperature, wind speed and direction is provided at the same hourly resolution at all stations. The details of the experimental sites and instruments used for the acquisition are given. Special attention is paid to the quality of the data and the procedure applied to flag suspicious or erroneous measurements is described in details. Between 88 and 99% of the daytime measurements are validated by this quality control. Except at Barrani where the number is lower (13500), between 20000 and 29000 measurements of global and diffuse hourly irradiation are available at all sites for the 7-year period. Similarly, from 9000 to 13000 measurements of direct hourly irradiation values are provided for the three sites where this component is measured. With its high temporal resolution this consistent irradiation and meteorological database constitutes a reliable source to estimate the potential of solar energy in Egypt. It is also adapted to the study of high-frequency atmospheric processes such as the impact of aerosols on atmospheric radiative transfer. In the next future, it is planned to complete regularly the present 2004-2010 database.

Biogeochemical measurements of cold seep sediments inhabit by vesicomyid clams in the Japan Deep Sea Trench

Vesicomyidae clams harbor sulfide-oxidizing endosymbionts and are typical members of cold seep communities associated with tectonic faults where active venting of fluids and gases takes place. We investigated the central biogeochemical processes that supported a vesicomyid clam colony as part of a locally restricted seep community in the Japan Trench at 5346 m water depth, one of the deepest seep settings studied to date. An integrated approach of biogeochemical and molecular ecological techniques was used combining in situ and ex situ measurements. During the cruise YK06-05 in 2006 with the RV Yokosuka to the Japan Trench, we investigated a clam colony inhabited by Abyssogena phaseoliformis (former known as Calyptogena phaseoliformis) and Isorropodon fossajaponicum (former known as Calyptogena fossajaponica). The targeted sampling and precise positioning of the in situ instruments were achieved with the manned research submersible Shinkai 6500 (JAMSTEC, Nankoku, Kochi, Japan). Sampling was first performed close to the rim of the JTC colony and then at the center. Immediately after sample recovery onboard, the sediment core was sub-sampled for ex situ rate measurements or preserved for later analyses. In sediment of the clam colony, low sulfate reduction (SR) rates (max. 128 nmol ml**-1 d**-1) were coupled to the anaerobic oxidation of methane (AOM). They were observed over a depth range of 15 cm, caused by active transport of sulfate due to bioturbation of the vesicomyid clams. A distinct separation between the seep and the surrounding seafloor was shown by steep horizontal geochemical gradients and pronounced microbial community shifts. The sediment below the clam colony was dominated by anaerobic methanotrophic archaea (ANME-2c) and sulfate-reducing Desulfobulbaceae (SEEP-SRB-3, SEEP-SRB-4). Aerobic methanotrophic bacteria were not detected in the sediment and the oxidation of sulfide seemed to be carried out chemolithoautotrophically by Sulfurovum species. Thus, major redox processes were mediated by distinct subgroups of seep-related microorganisms that might have been selected by this specific abyssal seep environment. Fluid flow and microbial activity was low but sufficient to support the clam community over decades and to build up high biomasses. Hence, the clams and their microbial communities adapted successfully to a low-energy regime and may represent widespread chemosynthetic communities in the Japan Trench.

Pedology, geochronology, palynology and macrofossils of soil profiles in the Altdarss area, german Baltic Sea coast

A new site with Lateglacial palaeosols covered by 0.8 - 2.4 m thick aeolian sands is presented. The buried soils were subjected to multidisciplinary analyses (pedology, micromorphology, geochronology, dendrology, palynology, macrofossils). The buried soil cover comprises a catena from relatively dry ('Nano'-Podzol, Arenosol) via moist (Histic Gleysol, Gleysol) to wet conditions (Histosol). Dry soils are similar to the so-called Usselo soil, as described from sites in NW Europe and central Poland. The buried soil surface covers ca. 3.4 km**2. Pollen analyses date this surface into the late Aller0d. Due to a possible contamination by younger carbon, radiocarbon dates are too young. OSL dates indicate that the covering by aeolian sands most probably occurred during the Younger Dryas. Botanical analyses enables the reconstruction of a vegetation pattern typical for the late Allerod. Large wooden remains of pine and birch were recorded.

Food composition of beryx-alfonsino over submarine rises near Azores

Qualitative and quantitative food composition, as well as intensity of feeding of beryx-alfonsino Beryx splendens was examined on banks near the Azores. Data are presented with respect to size groups and taking into account type of feeding of males and females. Crustaceans and fishes were constituents of their feeding ration. A tendency toward increase in the number of consumed fishes in the course of ontogenetic development of beryx-alfonsino was noted. Beryx-alfonsino was shown to occupy the trophic level of consumers of the third order performing function of a deep-water predator.

Results of biological and geological bottom investigations carried out during Cruise 43 of R/V Akademik Kurchatov in the South Atlantic

The book is devoted to investigations of benthic fauna and geology of the Southern Atlantic Ocean. These works have been carried out in terms of exploring biological structure of the ocean and are of great importance for development of this fundamental problem. They are based on material collected during Cruise 43 of R/V Akademik Kurchatov in 1985-1986 and Cruise 43 of R/V Dmitry Mendeleev in 1989. Problems of quantitative distribution, group composition and trophic structure of benthos in the Southern Scotia Sea, along the east-west Transatlantic section along 31°30'S, and offshore Namibia in the area of the Benguela upwelling are under consideration in the book. Authors present new data on fauna of several groups of deep-sea bottom animals and their zoogeography. Much attention is paid to analysis of morphological structure of the Scotia Sea floor considered in terms of plate tectonics. Bottom sediments along the Transatlantic section and facial variation of sediments in the area of South Shetland Islands and of the continental margin of Namibia are under consideration.

Table 1. Mean geochemical values for Baseline (pre-injection) and Monitor-1 (post-injection) samples, and the percent change between the two weighted means

The Weyburn Oil Field, Saskatchewan is the site of a large (5000 tonnes/day of CO2) CO2-EOR injection project By EnCana Corporation. Pre- and post-injection samples (Baseline and Monitor-1, respectively) of produced fluids from approximately 45 vertical wells were taken and chemically analyzed to determine changes in the fluid chemistry and isotope composition between August 2000 and March 2001. After 6 months of CO2 injection, geochemical parameters including pH, [HCO3], [Ca], [Mg], and ?13CO2(g) point to areas in which injected CO2 dissolution and reservoir carbonate mineral dissolution have occurred. Pre-injection fluid compositions suggest that the reservoir brine in the injection area may be capable of storing as much as 100 million tonnes of dissolved CO2. Modeling of water-rock reactions show that clay minerals and feldspar, although volumetrically insignificant, may be capable of acting as pH buffers, allowing injected CO2 to be stored as bicarbonate in the formation water or as newly precipitated carbonate minerals, given favorable reaction kinetics.

Composition and properties of rocks and sediments from the Cape Verde fracture zone

The book presents results of comprehensive geological and geophysical studies, carried out in the Cape Verde fault zone in the 3-rd cruise of R/V Akademik Nikolaj Strakhov (1986). Detailed characterization of bottom relief, thickness and structure of the sedimentary cover, magnetic field, crust structure, lithology and stratigraphy of sediments, petrography and geochemistry of magmatic rocks. Conclusions about tectonic layering of the crust and upper mantle in the fault zone, and about a concurrent structural section of large mantle inhomogeneities have been done. The book is the first monographic description of a major fault structure of the ocean floor.

Chemical and mineral compositions of sedimentary deposits and magmatic rocks from DSDP Legs 41, 45, 48, and 49

This collective monography by a group of lithologists from the Geological Institute of the USSR Academy of Sciences summarizes materials of the Deep-Sea Drilling Project from the Atlantic Ocean. It gives results of processing materials on the sequences drilled during DSDP Legs 41, 45, 48 and 49. These studies were based on lithological-facial analysis combined with detailed mineralogical-petrographic description. Its chapters give a number of ideas on formation of the Earth sedimentary cover, which can be used for compilation of regional and global schemes of ocean paleogeography, reconstruction of history of some structures in the World Ocean, correlation between sedimentary processes on continents and in oceans, estimation of perspectives for oil and gas fields and ore formation.

Abundance of nodules, chemical and mineral compositions of nodules and sediments from the Central Pacific

The monograph considers facial conditions of ore-formation in the Central Equatorial Pacific, as well as lithostratigraphy and local variability of bottom sediments. Mineral composition of nodules, forms of occurrence of chemical elements in sediments and nodules, composition of interstitial waters, age of nodules, regularities and processes of ore formation in the radiolarian belt of the Pacific Ocean zone are also under consideration.