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The use of trade measures to combat illegal, unreported and unregulated (IUU) fishing in the Northeast Atlantic has evolved from unilateral denial of the landing of fish taken outside international quota arrangements to a multilateral Scheme of Control and Enforcement under the North-East Atlantic Fisheries Commission (NEAFC). International trade rules have not constrained this development, mostly due to successful management of the interplay between international resource management and trade regimes. States protect resource management objectives from such constraint by inserting clauses that establish a normative hierarchy, or they employ various means for adapting IUU measures to the ‘environmental window’ of the global trade regime. The fact that regional states have introduced trade restrictions only when non-restrictive or less restrictive measures have failed enhances such compatibility, as do the gradual shift from unilateral to multilateral measures and the rise in transparency, openness and target-state involvement. None of those features reduces the effectiveness of regional trade measures; they minimize tension with trade commitments and largely strengthen their clout in the struggle to combat IUU fishing in the Northeast Atlantic. 相似文献
33.
Physiographically Controlled Allometry of Specific Sediment Yield in the Canadian Cordillera: A Lake Sediment-based Approach 总被引:2,自引:0,他引:2
Erik Schiefer Olav Slaymaker & Brian Klinkenberg 《Geografiska Annaler: Series A, Physical Geography》2001,83(1-2):55-65
It is generally supposed that specific sediment yield declines as the drainage basin area increases, as part of the mobilized sediment becomes trapped in the downstream cascade of storage zones. In British Columbia, using fluvial suspended sediment load data, Church and Slaymaker (Nature 1989, Vol 337, pp. 452–454) have observed a pattern of increasing specific sediment yield at all spatial scales up to 3×104 km2 . This trend has been attributed to the dominance of secondary remobilization of Quaternary sediments over primary denudation of the land surface. Using a larger data set of lake sediment-based estimates of long-term sediment yield, sub-regional patterns of specific yield have been investigated for the Canadian Cordillera. Between spatial scales of 0.9 and 190 km2 sediment yield trends are differentiated by physiography, as indicated by the variable allometry observed in the specific sediment yield–drainage basin area relations. Highest sediment yields were observed in the Coast Mountains where specific sediment yields conform to the regional pattern described by Church and Slaymaker. However, in flat-lying plateau and major valley areas specific sediment yield decreases with increasing drainage area, thus conforming to the conventional model of sediment delivery. In several other sub-regions of intermediate relief there were no significant relations between specific yield and drainage area. These results suggest that no single model of sediment yield is adequate to describe sediment transfer processes in the Canadian Cordillera at the sub-regional scale. 相似文献
34.
Heat flow taken between Svalbard and Greenland reveal three thermal provinces:
- 1. (1) the Molloy Ridge within the Spitsbergen Transform,
- 2. (2) the Yermak Plateau
- 3. (3) the northeastern margin of Svalbard (Nordaustlandet).
35.
Recent geophysical measurements, including multi-channel seismic reflection, on the Svalbard passive margin have revealed that it has undergone a complex geological history which largely reflects the plate tectonic evolution of the Greenland Sea and the Arctic Ocean. The western margin (75–80°N) is of a sheared-rifted type, along which the rifted margin developed subsequent to a change in the pole of plate rotation about 36 m.y. B.P. The north-trending Hornsund Fault on the central shelf and the eastern escarpment of the Knipovich Ridge naturally divide the margin into three structural units. These main marginal structures strike north, paralleling the regional onshore fault trends. This trend also parallels the direction of Early Tertiary plate motion between Svalbard and Greenland. Thus, the western Svalbard margin was initially a zone of shear, and the shear movements have affected the adjacent continental crust. Although, the nature and location of the continent—ocean crustal transition is somewhat uncertain, it is unlikely to lie east of the Hornsund Fault. The northern margin, including the Yermak marginal plateau, is terminated to the west by the Spitsbergen Fracture Zone system. This margin is of a rifted type and the preliminary analysis indicates that the main part of the investigated area is underlain by continental crust. 相似文献
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Theocharis Baxevanis Euripides Papamichos Olav Flornes Idar Larsen 《Acta Geotechnica》2006,1(2):123-135
The mechanical behavior and permeability of the Tuffeau de Maastricht calcarenite were studied. Compactions bands were found to form in the “transitional” regime between brittle faulting and cataclastic flow. In order to predict the formation of compaction bands, bifurcation analysis was applied on a model developed by Lade and Kim. The numerical results proved to be in good agreement with the experimental ones where the localization point was identified to be the onset of shear-enhanced compaction (a threshold in differential stress after which significant reduction of porosity is induced). Before the onset of shear-enhanced compaction, permeability was primarily controlled by the effective mean stress, independent of the deviatoric stresses. With the onset of shear-enhanced compaction, however, coupling of the deviatoric and hydrostatic stresses induced considerable permeability and porosity reduction. 相似文献
38.
Olav Vestøl 《Journal of Geodesy》2006,80(5):248-258
Precise leveling, tide-gauge recordings and time series from continuous GPS stations are all sources of information about the ongoing postglacial land uplift in Fennoscandia. This article describes how to gather these three sources of data together in a least-squares collocation adjustment in order to calculate uplift rates, as well as new heights for the benchmarks in the leveling network. The estimated reliability of the resulting uplift model is in general better than 0.4 mm/year, decreasing in areas of fewer data.A smoother and extended version of the land uplift model described here is used in the adjustment of the new height system in Sweden (RH 2000) under the name RH 2000 LU. Later on, the name was changed to NKG2005LU. The Finnish Geodetic Institute (FGI) has decided to use the same model when they calculate their new height system, N2000. 相似文献
39.
Contrasts in elastic parameters can be estimated directly from seismic data using offset-dependent information in the PP reflection coefficient. A linear approximation to the PP reflection coefficient including three coefficients is fitted to the data, and relative contrasts in various elastic parameters are obtained from linear combinations of the estimated coefficients. Linearized elastic parameter sections for the contrasts in P-wave impedance, P-wave velocity, density, plane-wave modulus, and the change in bulk modulus and shear modulus normalized with the plane-wave modulus are estimated. If the average P- to S-wave velocity ratio is known, linearized parameter sections including the contrast in the average P- to S-wave velocity ratio and a fluid factor section can be computed. Applied to synthetic data, visual comparison of the estimated and true elastic parameter sections agree qualitatively, and the results are confirmed by an analysis of the standard deviation of the estimated parameters. The parameter sections obtained by inversion of a shallow seismic anomaly in the Barents Sea are promising, but the reliability is uncertain because neither well data nor regional trends are available. 相似文献
40.