[1] Time-series observations of optical fields in the euphotic layer and particle fluxes at 150 m were made in the western North Pacific for half year of 2005. The ratio of surface photosynthetically available radiation (surface PAR) to in situ quantum irradiance at ca. 40 m (in situ QI), as an index of turbidity, began to increase in the middle of April, peaking between the end of June and the...

We have determined the relationship between carbon-specific photosynthesis and phytoplankton cell size in a coastal ecosystem. The normalized size spectra of carbon (C) biomass and photosynthesis allow to determine both biomass and photosynthesis within any size class along the community size spectrum. By dividing the size spectra of photosynthesis and biomass, the size spectrum of C-specific p...

The structure of the total and metabolically active communities of attached and free-living bacteria were analysed in the euphotic zone in the NW Mediterranean Sea with the use of DNA- and RNA-derived capillary electrophoresis single-strand conformation polymorphism fingerprinting. More than half (between 52% and 69%) of the DNA-derived operational taxonomic units (OTUs) were common in both att...

High-precision triple oxygen isotope data on 40 water samples (5–10 923 m in depth) collected at the Challenger Deep of Mariana Trench are reported this study. The analyses Laboratoire des Sciences du Climat et l’Environnement yield mean values δ18O = −0.084 ± 0.224‰, δ17O −0.061 0.117‰, and 17O-excess −17 5 per meg, with standard deviations 1σ. range (from −0.480 to 0.544‰) falls within record...

The export of organic carbon from the surface ocean by sinking particles is an important, yet highly uncertain, component of the global carbon cycle. Here we introduce a mechanistic assessment of the global ocean carbon export using satellite observations, including determinations of net primary production and the slope of the particle size spectrum, to drive a food-webmodel that estimates the ...

To overcome sinking, plankton have devised various types of strategies. One is swimming, that is, an active, energy-consuming self-propulsion than can oppose gravitational sinking. Other phytoplankters can modify their buoyancy, becoming, at least for some time, positively buoyant. Others can exploit the turbulence in the mixed layer, using it to stay suspended for longer times. This latter opt...

The phytoplankton of the world's oceans play an integral part in global carbon cycling and food webs by conversion of carbon dioxide into organic carbon. They accomplish this task through the action of the Calvin cycle enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO). Here we have investigated the phylogenetic diversity in the form I rbcL locus in natural phytoplankton communiti...

Aim We conduct the first model-based assessment of biogeographical subdivision Eurasian Arctic seas to (1) delineate spatial distribution and boundaries macrobenthic communities on a seascape level; (2) assess significance environmental drivers community structures; (3) compare our modelling results historical classifications; (4) couple model climate scenarios changes project potential shifts ...