Alkenone data of sediment traps off Cape Blanc, NW Africa

We analysed long-chain alkenones in sinking particles and surface sediments from the filamentous upwelling region off Cape Blanc, NW Africa, to evaluate the transfer of surface water signals into the geological record. Our study is based on time-series sediment trap records from 730 m (1990-1991) to 2195-3562 m depth (1988-1991). Alkenone fluxes showed considerable interannual variations and no consistent seasonality. The average flux of C37 and C38 alkenones to the deep traps was 1.9 µg/m**2/d from March 1988 to October 1990 and sevenfold higher in the subsequent year. Alkenone fluxes to the shallower traps were on average twice as high and showed similar temporal variations. The alkenone unsaturation indices UK'37, UK38Me and UK38Et closely mirrored the seasonal variations in sea-surface temperature (weekly Reynolds SST). Time lags of 10-48 days between the SST and unsaturation maxima suggest particle sinking rates of about 80 and 280 m/d for the periods of low and high alkenone fluxes, respectively. The average flux-weighted UK'37 temperature for the 4-year time series of the deeper traps was 22.1°C, in perfect agreement with the mean weekly SST for the same period. This and the comparison with seasonal temperature variations in the upper 100 m of the water column suggests that UK'37 records principally the yearly average of the mixed-layer temperature in this region. A comparison between the average annual alkenone fluxes to the lower traps (2400 µg/m**2/yr) and into the underlying sediments (4 µg/m**2/yr) suggests that only about 0.2% of the alkenones reaching the deep ocean became preserved in the sediments. The flux-weighted alkenone concentrations also decreased considerably, from 2466 µg/gC in the water column to 62 µg/gC in the surface sediments. Such a low degree of alkenone preservation is typical for slowly accumulating oxygenated sediments. Despite these dramatic diagenetic alkenone losses, the UK'37 ratio was not affected. The average UK'37 value of the sediments (0.796±0.010 or 22.3±0.3°C) was identical within error limits to the 4-year average of the lower traps. The unsaturation indices for C38 alkenones and the ratio between C37 and C38 alkenones also revealed a high degree of stability. Our results do not support the hypothesis that UK'37 is biased towards higher values during oxic diagenesis.

Thorium-234, POC and PON fluxes during POLARSTERN cruise ANT-XXVIII/3, January-March 2012

Carbon fixation by phytoplankton plays a key role in the uptake of atmospheric CO2 in the Southern Ocean. Yet, it still remains unclear how efficiently the particulate organic carbon (POC) is exported and transferred from ocean surface waters to depth during phytoplankton blooms. In addition, little is known about the processes that control the flux attenuation within the upper twilight zone. Here, we present results of downward POC and particulate organic nitrogen fluxes during the decline of a vast diatom bloom in the Atlantic sector of the Southern Ocean in summer 2012. We used thorium-234 (234Th) as a particle tracer in combination with drifting sediment traps (ST). Their simultaneous use evidenced a sustained high export rate of 234Th at 100 m depth in the weeks prior to and during the sampling period. The entire study area, of approximately 8000 km**2, showed similar vertical export fluxes in spite of the heterogeneity in phytoplankton standing stocks and productivity, indicating a decoupling between production and export. The POC fluxes at 100 m were high, averaging 26 ± 15 mmol C/m**2/d, although the strength of the biological pump was generally low. Only <20% of the daily primary production reached 100 m, presumably due to an active recycling of carbon and nutrients. Pigment analyses indicated that direct sinking of diatoms likely caused the high POC transfer efficiencies (~60%) observed between 100 and 300 m, although faecal pellets and transport of POC linked to zooplankton vertical migration might have also contributed to downward fluxes.

Leyes expedidas por el congreso nacional.

Title varies.

Zemirot Yiśraʾel.

Hebrew words (transliterated); caption titles not transliterated.

La Esmeralda : opera seria in 5 atti.

Libretto by Victor Hugo, based on his novel, Notre-dame de Paris; translated into Italian by the composer. Cf. Fétis. Biog. univ. des musiciens, 2. éd., suppl., v. 2, p. 85.

Ausgewählte Werke für den praktischen Gebrauch /

Errata slip inserted in Bd. 5, No. 1.

Histoire diplomatique de l'Europe depuis le Congrès de Berlin jusqu'à nos jours,

"Faisant suite à l'ouvrage du même auteur, Histoire diplomatique de l'Europe depuis l'ouverture du Congrès de Vienne jusqu'à la clôture du Congrès de Berlin (1814-1878)", Paris, 1891.

Ethnogénie gauloise, ou Mémoires critiques sur l'origine et la parenté des Cimmériens, des Cimbres, des Ombres, des Belges, des Ligures, et des anciens Celtes,

Vol. 1-2, 2. éd. 1872-5.

L'Espagne et Napoléon.

Vols. 1: 2. éd.; v. 2: 2. éd; v. 3: 3. éd.

La duchesse de Bourgogne et l'alliance savoyarde sous Louis XIV,

I. La réconciliation avec la Savoie et le mariage de la duchesse de Bourgogne. 2. éd.--II. Les années heureuses et la rupture de l'alliance.--III. Le duc de Bourgogne à l'armée; les années d'épreuves.--IV. L'avant-règne et la mort. Épilogue de l'alliance savoyarde. Table analytique.

Wisconsin day care news and views.

WI docs no.: Chi.6/2:D 3/4/195 -1962

Sistema de cirugia /

Mode of access: Internet.

Sistema de cirugia /

Mode of access: Internet.

Artemidori Daldiani & Achmetis Sereimi F. Oneirocritica : Astrampsychi [et] Nicephori versus etiam Oneirocritici /

Mode of access: Internet.

Dictionary of organic compounds; the constitution and physical and chemical properties of the principal carbon compounds and their derivatives, together with the relevant literature references.

Errata slips inserted.