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61.
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
62.
Matsumoto Takeshi Goslin Jean Lagabrielle Yves Ruellan Etienne Tanahashi Manabu 《Marine Geophysical Researches》1997,19(1):37-53
A surface ship gravity survey was carried out in the northern part of the North Fiji Basin during the NOFI cruise by the R/V l'Atalante in August-September, 1994. The two ridges inside the study area, the South Pandora Ridge and the Tripartite Ridge, present different structures and states of isostatic equilibrium in terms of gravity anomaly and its tectonic implications. The former is supported by a restoring force of an imaginary elastic plate in the crust and the latter by the Airy type isostasy. These characteristics can be derived from the difference in magmatic activity, as influenced by the difference in lithospheric structure. The latter is characterised by greater active magmatism and hydrothermalism underneath the ridge than the former. Such a difference in the magmatic activity and the horizontal scale of the shallow subsurface structure is derived from the difference in the stiffness or viscosity of the lithosphere beneath the two ridges. 相似文献
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68.
Identification of Danish North Sea trawl fisheries 总被引:1,自引:3,他引:1
69.
本文采用1985年12月12日至1986年2月8日“向阳红14”号调查船在太平洋调查所获海洋水文气象资料,计算了四种热交换量。结果表明:海-气热输送与天气系统和海洋水文条件关系密切。冬季,在各种天气系统条件下西太平洋及中太平洋的大气主要是从海洋得到热量,其中以黑潮流经的海域最为明显,而热交换的方式主要是海洋以潜热的形式把热量输送给大气。 相似文献
70.
Short-Term Benthic Recolonization after Dredging in the Harbour of Ceuta, North Africa 总被引:2,自引:0,他引:2
Abstract. The benthic recovery after dredging (area: 2625 m2) was studied in a polluted and enclosed area of the harbour of Ceuta, in which the recolonization through the water column (larvae and adult bedload transport) could be limited by the lack of renewal. The benthos was sampled at two sites (control and dredged) using a van Veen grab and adopting a BACI (Before, After, Control, Impacted) approach. Five samplings were conducted after dredging (3, 15, 30, 90, 180 days). The proportion of gravel in the sediment of the dredged site increased after dredging, while the organic matter decreased. The impact on the community was estimated at species level, using both univariate and multivariate analyses. The maximum negative effect on benthic macrofauna was a reduction by 65% for species richness (15 days after dredging) and by 75% for abundance (3 days after dredging). Between 15 and 30 days after dredging, the abundance of some species such as the molluscs Parvicardium exiguum and Retusa obtusa and the polychaete Pseudomalacoceros tridentata increased considerably in the dredged site, while typical ‘opportunistic’ species such as Capitella capitata were disfavoured by the disturbance. For this small‐scale dredging, about 6 months are required for the disturbed area to re‐establish a sediment structure and a macrobenthic community similar to the undisturbed area. Small‐patch dredging operations are proposed in harbour management whenever possible, since they allow a quick re‐adjustment of the initial sediment structure and benthic communities. 相似文献