Assimilation and turnover rates of lipid compounds in dominant Antarctic copepods fed with C-enriched diatoms.

The study revealed species- and stage-specific differences in lipid accumulation of the dominant Antarctic copepods, the primarily herbivorous (copepodite stage V (CV), females) and the more omnivorous (females) storing wax esters and triacylglycerols, respectively, which were collected in summer (end of December). Feeding carbon-labelled diatoms to these copepods, C elucidated assimilation and turnover rates of copepod total lipids as well as specific fatty acids and alcohols. The C incorporation was monitored by compound-specific stable isotope analysis (CSIA).

Stoichiometry, polarity, and organometallics in solid-phase extracted dissolved organic matter of the Elbe-Weser estuary.

Dissolved organic matter (DOM) is ubiquitous in natural waters and plays a central role in the biogeochemistry in riverine, estuarine and marine environments. This study quantifies and characterizes solid-phase extractable DOM and trace element complexation at different salinities in the Weser and Elbe River, northern Germany, and the North Sea. Dissolved organic carbon (DOC), total dissolved nitrogen (TDN), Co and Cu concentrations were analyzed in original water samples.

Lipid and fatty acid/alcohol compositions of the subarctic copepods Neocalanus cristatus and Eucalanus bungii from various depths in the Oyashio region, western North Pacific.

Lipids of Neocalanus cristatus and Eucalanus bungii (C3 to adults), collected in March, May, and December from various depths (0-2000m) were studied in the Oyashio region, western North Pacific. Total lipid and wax ester contents of younger N. cristatus stages increased during the development, being higher in May than in March and December.

Seasonal baseline of nutrients and stable isotopes in a saline lake of Argentina: biogeochemical processes and river runoff effects.

The seasonal variability of inorganic and organic nutrients and stable isotopes and their relations with plankton and environmental conditions were monitored in Lake Chasicó. Principal component analysis evidenced the strong influence of the river runoff on several biogeochemical variables. Silicate concentrations were controlled by diatom biomass and river discharge.

Inorganics in organics: quantification of organic phosphorus and sulfur and trace element speciation in natural organic matter using HPLC-ICPMS.

A method is presented for the chemical characterization of natural organic matter (NOM). We combined reversed-phase chromatographic separation of NOM with high resolution inductively coupled plasma mass spectrometry. A desolvation technique was used to remove organic solvent derived from the preceding chromatographic separation.