Checklist of marine and estuarine fishes from the Alaska–Yukon Border, Beaufort Sea, to Cabo San Lucas, Mexico

This paper is a checklist of the fishes that have been documented, through both published and unpublished sources, in marine and estuarine waters, and out 200 miles, from the United States-Canadian border on the Beaufort Sea to Cabo San Lucas, Mexico. A minimum of 241 families and 1,644 species are known within this range, including both native and nonnative species. For each of these species, we include maximum size, geographic and depth ranges, whether it is native or nonnative, as well as a brief mention of any taxonomic issues.

CONTENT OF SUSPENDED SUBSTANCES IN MACROPRIENT ESTUARIES OF THE WHITE AND BARENTS SEA RIVERS

The statistical characteristics of the content of suspended matter in the macrotidal estuaries of the Kuloi River with a lateral tributary of the Pocha, the Pyya River (White Sea) and the Chesha River in the Barents Sea. Their maximum values in the surface layers of estuarine waters due to the roiling of bottom sediments by tidal currents can reach a level of 500–4000 mg/l and even more. The typical range of fluctuations in the concentration of suspended matter in such river mouths will be 90–720 mg/l for taiga rivers and 200–1830 mg/l for tundra rivers. The higher turbidity of the estuarine waters of the tundra zone is associated with the degradation of its permafrost soils against the background of the observed climate warming. The relationship between suspended solids and salinity distribution at the mouths of small rivers may differ markedly from the conditions observed at the mouths of medium and large rivers.

Redox Speciation of Vanadium in Estuarine Waters Using Improved Methodology Based on Anion Exchange Chromatography Coupled to HR ICP-MS System

An improved methodology was developed for V redox speciation in estuarine waters using a hyphenated technique consisting of ion chromatograph (IC) with an anion exchange column and a high-resolution inductively coupled plasma mass spectrometer (HR ICP-MS). This approach enables the direct determination of V(V), whereas reduced species (mainly V(IV)) are calculated by subtracting V(V) concentrations from the measured total V concentration. Based on the “on-column” V(V) chelation mechanism by EDTA, with the eluent composed of 40 mmol L−1 ammonium bicarbonate, 40 mmol L−1 ammonium sulphate, 8 mmol L−1 ethylenediaminetetraacetic acid and 3% acetonitrile, the method was successfully used for analyses of V redox speciation in samples taken in the vertical salinity gradient of the highly stratified Krka River estuary. Due to the matrix effects causing different sensitivities, a standard addition method was used for V(V) quantification purposes. The limit of detection (LOD) was also found to be matrix related: 101.68 ng L−1 in the seawater and 30.56 µg L−1 in the freshwater. Performed stability tests showed that V redox speciation is preserved at least 7 days in un-treated samples, possibly due to the stabilization of V-reduced species with natural organic matter (NOM). The dominant V form in the analysed samples was V(V) with the reduced V(IV) accounting for up to 26% of the total dissolved pool. The concentration of V(IV) was found to correlate negatively with the oxygen concentration. Significant removal of dissolved V was detected in oxygen depleted zones possibly related to the particle scavenging.