Similar to their tropical counterparts, cold-water corals (CWCs) are able to build large three-dimensional reef structures. These unique ecosystems are at risk due to ongoing climate change. In particular, ocean warming, ocean acidification and changes in the hydrological cycle may jeopardize the existence of CWCs. In order to predict how CWCs and their reefs or mounds will develop in the near future one important strategy is...

Thaumarchaea are among the most abundant microbial groups in the ocean, but controls on their abundance and the distribution and metabolic potential of different subpopulations are poorly constrained. Here, two ecotypes of ammonia‐oxidizing thaumarchaea were quantified using ammonia monooxygenase ( amoA ) genes across the equatorial Pacific Ocean. The shallow, or water column “A” (WCA), ecotype was the most abundant ecotype at...

The Arabian Sea is a productive basin where seasonal upwelling and convective mixing result in high surface nutrient concentrations and widespread algal blooms. The factors controlling primary productivity in the Arabian Sea are of interest because the region contains an intense oxygen minimum zone (OMZ) that is a major sink for nitrate in the ocean. A survey of iron (Fe) distribution and redox chemistry was carried out in 200...

Vertical profiles of total dissolved iron (DFe), Fe(II), and hydrographic parameters were obtained along three transects across the continental shelf off Peru in October 2005. Fe(II) and DFe concentrations were determined using luminol chemiluminescence and isotope dilution inductively coupled plasma mass spectrometry (ICP‐MS), respectively. The objective was to study the relationships among redox chemistry, nitrogen‐cycle pro...

We present full‐depth zonal sections of total dissolved cobalt, iron, manganese, and labile cobalt from the South Atlantic Ocean. A basin‐scale plume from the African coast appeared to be a major source of dissolved metals to this region, with high cobalt concentrations in the oxygen minimum zone of the Angola Dome and extending 2500 km into the subtropical gyre. Metal concentrations were elevated along the coastal shelf, like...

We discuss the concept of colimitation of primary productivity in aquatic environments, with an emphasis on reconciling this concept with recent advances in marine bioinorganic chemistry. Colimitations are divided into three categories on the basis of their mathematical formulations and visualizations: type I, independent nutrient colimitation (e.g., N and P); type II, biochemical substitution colimitation (e.g., Co and Zn); a...

We present evidence demonstrating the capability of Phaeocystis antarctica colonies to substitute cobalt (Co) and zinc (Zn) as micronutrients, in which Co limitation is alleviated by additions of Zn and vice versa. Maximal growth rates and biomass were determined by fluorescence and the values obtained under replete Zn and no added Co conditions were significantly higher than under replete Co and no added Zn conditions, sugges...

Glutathione is an abundant intracellular thiol that is involved in the detoxification of reactive oxygen species generated in the presence of light. We used short‐term continuous cultures of Emiliania huxleyi and Thalassiosira pseudonana to show that a diurnal light cycle causes intracellular glutathione to undergo at least twofold variations, with maximum concentrations occurring during light periods. Cysteine concentrations...