Acidobacteria constitute a still poorly studied phylum that is well represented in soils. Recent studies suggest that members of this phylum may be also abundant in deep-sea plankton, but their relative abundance and ecological role in this ecosystem are completely unknown. A recent screening of three metagenomic deep-sea libraries of bathypelagic plankton from the South Atlantic (1000 m depth)...

[1] Satellite measurements allow global assessments of phytoplankton concentrations and, from observed temporal changes in biomass, direct access to net biomass accumulation rates (r). For the subarctic Atlantic basin, analysis of annual cycles in r reveals that initiation of the annual blooming phase does not occur in spring after stratification surpasses a critical threshold but rather occurs...

The pre-Ediacaran biomarker record has several characteristic features that distinguish it from its Phanerozoic counterpart, including high concentrations of unresolved complex mixture (UCM), low concentrations or absence of eukaryotic steranes, and a conspicuous carbon isotopic enrichment of n-alkyl lipids relative to bulk sedimentary carbon. We propose that these derive from a common, non-act...

Abstract Copepods of the genera Calanus and Pseudocalanus are important components Arctic marine ecosystems. Despite key roles these zooplankters, little is known about organisms they interact with most intimately, their parasites symbionts. We applied metabarcode sequencing to uncover eukaryotic present within two copepod from three areas around high archipelago Svalbard. Ten distinct parasite...

The seasonal succession of all major planktonic groups, i.e., phytoplankton, bacteria, heterotrophic flagellates, ciliates, rotifers, and crustaceans, was investigated during five years (1987-1991) of weekly sampling with elaborate sampling methods and microscopic countings. This allows to study the seasonal changes of the biomass and production allocation patterns within the epilimnetic food w...

Dissolved organic matter (DOM) in the ocean represents about 662 billion tons of C, 200 times more than living biomass. It is produced mainly by microbial primary production. The largest fraction this DOM old (>weeks to months) and both chemically biologically recalcitrant. remainder young (seconds weeks), labile surface active. Part latter changes rheological properties bulk phase water at ...

Increasing concentrations of atmospheric carbon dioxide are projected to lead to an increase in sea surface temperatures, potentially impacting marine ecosystems and biogeochemical cycling. Here we conducted an indoor mesocosm experiment with a natural plankton community taken from the Baltic Sea in summer. We induced a plankton bloom via nutrient addition and followed the dynamics of the diffe...

Marine ecosystems are undergoing substantial changes due to human-induced pressures. Analysis of long-term data series is a valuable tool for understanding naturally and anthropogenically induced changes in plankton communities. In the present study, seasonal monitoring data were collected in three sub-basins of the northern Baltic Sea between 1979 and 2011 and statistically analysed for trends...

We studied the effects of future climate change scenarios on plankton communities of a Norwegian fjord using a mesocosm approach. After the spring bloom, natural plankton were enclosed and treated in duplicates with inorganic nutrients elevated to pre-bloom conditions (N, P, Si; eutrophication), lowering of 0.4 pH units (acidification), and rising 3°C temperature (warming). All nutrient-amended...