Continuous daylight in the high-Arctic summer supports high plankton respiration rates compared to those supported in the dark.

Plankton respiration rate is a major component of global CO production and is forecasted to increase rapidly in the Arctic with warming. Yet, existing assessments in the Arctic evaluated plankton respiration in the dark. Evidence that plankton respiration may be stimulated in the light is particularly relevant for the high Arctic where plankton communities experience continuous daylight in spring and summer.

Strong Seasonality of Marine Microbial Eukaryotes in a High-Arctic Fjord (Isfjorden, in West Spitsbergen, Norway).

The Adventfjorden time series station (IsA) in Isfjorden, West Spitsbergen, Norway, was sampled frequently from December 2011 to December 2012. The community composition of microbial eukaryotes (size, 0.45 to 10 μm) from a depth of 25 m was determined using 454 sequencing of the 18S V4 region amplified from both DNA and RNA.

New production regulates export stoichiometry in the ocean.

The proportion in which carbon and growth-limiting nutrients are exported from the oceans' productive surface layer to the deep sea is a crucial parameter in models of the biological carbon pump. Based on >400 vertical flux observations of particulate organic carbon (POC) and nitrogen (PON) from the European Arctic Ocean we show the common assumption of constant C:N stoichiometry not to be met. Exported POC:PON ratios exceeded the classical Redfield atomic ratio of 6.

Partitioning of polychlorinated biphenyls between Arctic seawater and size-fractionated zooplankton.

Concentrations of hydrophobic organic contaminants in zooplankton have been hypothesized to be governed by either near-equilibrium partitioning with surrounding water, growth dilution, or biomagnification. Concentrations of 17 polychlorinated biphenyls (PCBs) were measured in size-fractionated zooplankton, in phytoplankton (> 0.7 microm), and in the dissolved water phase (< 0.