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41.
Toshiro Saino Alexander Bychkov Chen-Tung Arthur Chen Paul J. Harrison 《Journal of Oceanography》2004,60(1):1-4
This special issue is comprised of 13 papers, including this overview, and focuses on the synthesis of the Joint Global Ocean
Flux Study (JGOFS) in the North Pacific which took place from 1997 through 2003. The effort was led by the JGOFS North Pacific
Synthesis Group, with the aim of quantifying CO2 drawdown by physical and biological pumps in the North Pacific by identifying and studying the regional, seasonal to inter-annual
variations in the key processes, and understanding their regulating mechanisms. Emphasis was placed on the similarities and
differences of the biogeochemical regimes in the eastern and western subarctic Pacific. Effort was also made to address the
future research directions which arose from the scientific findings during the North Pacific JGOFS process study. A brief
overview of the papers from view points of CO2 drawdown by physical and biological pumps, spatial variability, and temporal variability from seasonal to decadal scales
is made, followed by suggestions for the directions of future research.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
42.
A 3-year program, to determine spatial and temporal trends in sediment concentrations of hydrocarbons and metals from oil and gas exploration and development activities, was conducted in the US Beaufort Sea. Concentrations of saturated and aromatic hydrocarbons in sediments from the Beaufort Sea were elevated in comparison to non-polluted shelf-sediments from other regions of the US coast. Potential natural sources for hydrocarbons that were examined included riverine sediments and coastal peat. Significant quantities of fossil hydrocarbons characterize the surface sediments from the entire region. Sediment inputs from river discharges appear to account for this observation. The use of source-diagnostic ratios has allowed the differentiation of various sources in an area with high naturally-occurring hydrocarbon concentrations where effects due to oil and gas exploration and development activities may be obscured. 相似文献
43.
Brent L. Lewis Pamela D. Holt Steven W. Taylor Steven W. Wilhelm Charles G. Trick Alison Butler George W. Luther III 《Marine Chemistry》1995,50(1-4)
Thermodynamic stability constants have been estimated for the complexation of iron(III) with catecholate-type siderophores isolated from the marine bacterium Alteromonas luteoviolacea and from the marine cyanobacterium Synechococcus sp. PCC 7002. Stability constants were determined utilizing the “chelate scale” of Taylor et al. (1994). The scale is based upon a linear relationship between the reduction potentials and the pH-independent thermodynamic stability constants for known iron(III) complexes. Log K values for the alterobactin B ferric iron complex are 43.6 ± 1.5 at pH 8.2 and 37.6 ± 1.2 at pH 6, consistent with a shift from bis-catecholate to monosalicylate/monocatecholate iron coordination with decreasing pH. Synechococcus isolates PCC 7002 Nos. 1 and 3 formed iron(III) complexes with stability constants of approximately 38.1 ± 1.2 and 42.3 ± 1.5, respectively. The binding strengths of the iron(III) complexes examined in this study are quite high, suggesting that catecholate siderophores may play a role in the solubilization and biological uptake of iron in the marine environment. 相似文献
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Interannual variability in Nordic seas primary production 总被引:1,自引:0,他引:1
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