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1.
Abstract

The concept of a bioeconomy has been placed central in formation of a Swedish National Forest Program (NFP). Drawing on Hajer’s conceptual framework of storylines, we present a discourse analysis of the working group reports underlying the establishment of the NFP strategy. We ask what stories about Swedish forests come to dominate the NFP process, how well they reflect the commitment of balancing economic, social and environmental interests, and what role the concept of a bioeconomy, has on the formation of these stories. Storylines of Swedish forests in the bioeconomy unite wider European discourses on the bioeconomy and climate change with historical Swedish forest policy discourses, revitalizing a discourse coalition comprising the state and the industry. Particular to the Swedish discourse is the strong emphasis on creating consensus around a single story of the forest-based bioeconomy.  相似文献   
2.
A large-scale contourite drift complex has been recognised on multi-channel 2D reflection seismic data acquired in the south-eastern Davis Strait and adjacent Labrador Sea slope offshore West Greenland between 63°?C66°N. Based on well-tie data, the drift complex developed from the Middle Miocene to the Recent. It has been mapped in a wide variety of water depths ranging from about 700?m, at a NNW-ESE-elongated crest located above structural highs in the Davis Strait, to more than 2,000?m beyond the slope to the Labrador Sea. The overall drift geometry has been described by subdivision into two first-order seismic units, enabling the generation of time-isochore maps. The reflection patterns demonstrating current-related deposition are illustrated by seismic examples. The time-isochores of the two first-order seismic units show lateral changes in their depocentres: the lower unit is absent in a zone slightly displaced south-westwards of the present-day crest, indicating changes in the prevailing deepwater current system during the Early Pliocene. The observations can be explained by two alternative palaeoceanographic scenarios: (1) either the present-day oceanographic setting with Arctic?CAtlantic water exchange across the Davis Strait was largely established by the mid-Miocene, with only minor adjustments during the Early Pliocene caused by tectonic movements, or (2) it became established during the Early Pliocene as a consequence of enhanced northward flow across the Davis Strait due to lowering of the sill depth.  相似文献   
3.
A regional correlation of Neogene stratigraphy has been attempted along and across the NW European Atlantic continental margin, between Mid-Norway and SW Ireland. Two unconformity-bounded successions are recognised. These are referred to as the lower and upper Neogene successions, and have been dated as Miocene–early Pliocene and early Pliocene–Holocene, respectively, in age. Their development is interpreted to reflect plate-wide, tectonically driven changes in the sedimentary, oceanographic and latterly climatic evolution of the NE Atlantic region. The lower Neogene succession mainly preserves a record of deep-water sedimentation that indicates an expansion of contourite sediment drifts above submarine unconformities, within this succession, on both sides of the eastern Greenland–Scotland Ridge from the mid-Miocene. This is interpreted to record enhanced deep-water exchange through the Faroe Conduit (deepest part of the Southern Gateway), and can be linked to compressive inversion of the Wyville–Thomson Ridge Complex. Thus, a pervasive, interconnected Arctic–North Atlantic deep-water circulation system is a Neogene phenomenon. The upper Neogene succession records a regional change, at about 4 Ma, in the patterns of contourite sedimentation (submarine erosion, new depocentres) coeval with the onset of rapid seaward-progradation of the continental margin by up to 100 km. This build-out of the shelf and slope is inferred to record a marked increase in sediment supply in response to uplift and tilting of the continental margin. Associated changes in deep-water circulation may be part of an Atlantic-wide reorganisation of ocean bottom currents. Glacial sediments form a major component of the prograding shelf margin (shelf-slope) sediment wedges, but stratigraphic data indicate that the onset of progradation pre-dates significant high-latitude glaciation by at least 1 Ma, and expansive Northern Hemisphere glaciation by at least 3 Ma.  相似文献   
4.
Based on studies of sediment accumulations deposited from-and erode by-alongslope flowing ocean currents on the European continental margin from Porcupine (Ireland) to Lofoten (Norway), the evolution of the Cenozoic paleocirculation was reconstructed as part of the STRATAGEM project. There is evidence of ocean current-controlled erosion and deposition in the Rockall Trough, in the Faeroe-Shetland Channel and on the Vøring Plateau since the late Eocene, although the circulation pattern remains ambiguous. The late Palaeogene flow in the Rockall Trough was almost probably driven by southerly-derived Tethyan Outflow Water. The extent and strength of any northerly-derived flow is uncertain. From the early Neogene (early-mid-Miocene), there was a massive regional expansion of contourite drift development both in the North Atlantic and in the Norwegian-Greenland Sea. This was most probably related to the development of the Faroe Conduit, the opening of the Fram Strait and the general subsidence of the Greenland-Scotland Ridge. These may have combined to cause a considerable acceleration in the exchange and overflow of deep waters between the Arctic and Atlantic Oceans. An early late Neogene (late early Pliocene) regional erosional event has been ascribed to a vigorous pulse of bottom-current activity, most probably the result of a global reorganisation of ocean currents associated with the closure of the Central American Seaway. During the late Neogene, contourites and sediment drifts developed in deep-water basins, between units of glacigenic sediments as well as infill of several paleo-slide scars. These sediments were derived from areas of bottom-current erosion as well as from the development of Plio-Pleistocene prograding sediment wedges, incorporating the extensive sediment supply derived from shelf-wide ice sheets. Presently a profound winnowing prevails along the shelf and upper slope due to the inflowing currents of Atlantic water. Depocentres of sediments derived from the winnowing are located (locally) in lower slope embayments and in slide scars.  相似文献   
5.
The inflow of Atlantic Water to the Nordic seas from mid–late Younger Dryas to earliest Holocene (12 450–10 000 a BP) is reconstructed on the basis of a high‐resolution core (LINK14) from 346 m water depth on the east Faroe shelf. We have analysed the distribution of planktic and benthic foraminifera, stable isotopes and ice‐rafted debris (IRD), and calculated absolute temperatures and salinities by transfer functions. During the investigated time period there was almost continuous inflow of Atlantic Water to the Nordic seas. Deposition of IRD during the mid–late Younger Dryas and Pre‐Boreal coolings indicates the presence of melting icebergs and that summer sea surface temperatures were low. The east–west temperature gradient across the Faroe–Shetland Channel was much steeper than today. The cold conditions around the Faroe Islands are attributed to stronger East Greenland and East Icelandic currents than at present. The near‐continuous inflow of Atlantic Water is consistent with published evidence suggesting that deep convection took place in the Nordic seas, although the convection sites probably had shifted to a more easterly position than at present. Around the time of deposition of the Saksunarvatn Tephra c. 10 350 a BP, sea surface temperatures increased to the present level. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
6.
The east Greenland margin has been influenced by oceanographic and cryospheric processes since the late Miocene, when the southwards flow of the East Greenland Current (EGC) initiated and ice sheets first advanced across the margin. However, the relative importance of these processes, and their influence on the sedimentation of the margin through time remains poorly understood. High‐resolution single‐channel seismic, chirp sub‐bottom profiles and swath bathymetry data were acquired along the middle/lower slope and proximal basinal area off Liverpool Land, central‐east Greenland margin. In this study, seismic‐stratigraphical and morphological analyses allowed us to distinguish between the major sedimentary processes that influenced this margin during the Quaternary. The stratigraphical architecture reveals mass transport deposits (MTDs) related to glacially influenced down‐slope sedimentation. These are intercalated with buried contourite systems associated with bottom‐current controlled along‐slope sedimentation. The distribution of the MTDs suggests the influence of two distinct ice‐stream systems. Initial phases of down‐slope deposition during the early‐middle Quaternary appears to be related to distal deposition fed by an ice stream from the Scoresby Sund area in the south. Shallow sedimentary processes, together with morphological analysis of the sea floor, show that the most recent activity of down‐slope processes during the latest Quaternary has occurred in the north, linked to an ice stream from the Kong Oscar Fjord area. These observations document a temporal shift in the relative dominance of the Scoresby Sund and Kong Oscar Fjord ice‐stream systems. The glacial influence on the margin has been interrupted by periods of stronger activity of along‐slope bottom‐current flow, demonstrating that the EGC periodically controlled sedimentation on the continental margin.  相似文献   
7.
ICZM (Integrated Coastal Zone Management) is a decision-making process for sustainable use, development and protection of coastal marine areas and their resources, in continuous realization. Norway is currently dependent upon the commitment and motivations of the municipalities to fulfill its ICZM initiatives. These communities are lacking epistemic communities that can help prevent the simmering conflicts surrounding aquaculture expansion, as demonstrated by media data from 1984–2010. With the forthcoming harvest of the zooplankton redfeed in Norwegian and surrounding waters, the Aquaculture industry could be in a situation of expanded feed resources, which would ensure its expansion if localities are made available. This would also be in line with the Norwegian government's commitment to the expansion of this industry. A government-endorsed growth of the Aquaculture industry will add fuel to these simmering conflicts concerning the use of the eco-system of collective goods and services available along national coastline in Norway for Aquaculture purposes. The suggestions from the recently released report from the Select Committee appointed by the Ministry of Fisheries and Coastal Affairs in Norway on Effective and Sustainable Area Use in the Aquaculture Industry cab be an aid to supporting the growth of epistemic communities and a subsequent successful national ICZM implementation, thereby paving the way for a conflict-less coastal area management.  相似文献   
8.
Effects of elevated seawater temperature show high spatial heterogeneity and variation within and among coral species. The objective of this study was to investigate how two coral species, Porites lutea and Galaxea fascicularis, from two high latitude reefs differently exposed to chronic disturbance, respond to elevated seawater temperatures. Corals were collected from reefs nearshore (i.e. subjected to high sediment load, higher chlorophyll α concentrations, turbidity etc.) and offshore (i.e. less exposed). The corals were exposed in the lab to gradually increasing temperatures (25.5-33.5?°C) for 72?h after which they were allowed to recover to ambient temperature (25.5?°C) for 24?h. Production and respiration were measured after 24, 48, 72 and 96?h. The results show that P. lutea from nearshore reefs suffered an initial decrease in gross primary production/respiration (GP/R) ratio after 24?h, after only a moderate temperature increase (+2?°C, from 25.5 to 27.5?°C), while there was no difference in GP/R ratio between heat-exposed and controls the other days, indicating that the chronic disturbance in the nearshore reef had no effect on their thermotolerance. Furthermore, P. lutea from the offshore reef showed a decrease in GP/R ratio both after 24?h and 72?h (33.5?°C) of exposure. In comparison, G. fascicularis showed a decrease in GP/R ratio after 48?h, 72?h and 96?h of exposure for the nearshore corals. Also, after 72?h these corals had withdrawn their polyps. There were no differences between heat-treated and controls for the offshore G. fascicularis. This implies that the chronically disturbed G. fascicularis had lower thermotolerance when exposed to a temperature increase. This study, hence, shows that the response of corals to elevated seawater temperature varies with species and environmental background history.  相似文献   
9.
The Maastrichtian chalk of the southern Central Graben, Danish North Sea, is a homogeneous pure white coccolithic chalk mudstone deposited in a deep epeiric shelf sea, which covered large parts of northern Europe. The sediment displays a pronounced cyclicity marked by decimetre‐thick bioturbated beds alternating with slightly thinner non‐bioturbated, mainly laminated beds. The laminated half‐cycles consist of alternating millimetre‐thick, graded, high‐porosity laminae and non‐graded, low‐porosity laminae. The cyclicity has been interpreted previously as caused by periods of slow background sedimentation and bioturbation interrupted by periods of rapid deposition of laminated beds, with the latter reflecting random and local resedimentation processes. Based on textural and structural analysis, the millimetre‐scale, non‐graded laminae are interpreted as having been deposited directly from pelagic rain of pelleted coccoliths representing the primary production. The graded laminae were deposited from small‐volume, low‐density turbidity currents and suspension clouds. The sedimentation rates of the cyclical chalk are similar to those known elsewhere, and the lamination is interpreted as having been preserved from destruction through bioturbation by anoxic conditions at the seafloor. Bioturbated–laminated cycles are thus formed by slow sedimentation during alternating seafloor redox conditions probably on a Milankovitch scale. A direct implication of this interpretation is that the cycles are areally widespread, probably extending throughout the southern Central Graben area and may be useful for correlation and high‐resolution cyclostratigraphy in the chalk fields of the Danish North sea. If the laminated half‐cycles represent a few rapid resedimentation events, with a high sedimentation rate as suggested by most workers, then the sediment would not be truly cyclic, but would represent event sedimentation within a pelagic background represented by the bioturbated beds. In this case, the cycles would have very limited potential for correlation.  相似文献   
10.
A complex history of Cenozoic vertical movements in the Faroe region has been revealed from interpretation of geophysical and geological data, mainly offshore reflection seismic data, side-scan images, shallow cores, and onshore mapping. The history comprises several phases of tectonic disturbances observed at different scales. On the eastern margin of the Faroe Platform a late Eocene–early Oligocene phase of doming of the Faroe Platform has caused a postdepositional tilting of Eocene strata along the southern margin of the platform; a mid-Miocene phase of compressional tectonics is evidenced on seismic transects as gentle anticlines and associated reverse faults; and possible Pliocene uplift of the Faroe Islands is indicated by a progradational wedge of sediments deposited on the eastern Faroe Platform. At the continental margin/slope north of the Faroe Platform, reflection seismic data imaging the postbasalt sedimentary strata indicate three distinct tectonic events phases in the Eocene–Oligocene, Miocene and Pliocene, respectively. In contrast to the Faroe Platform the Faroe–Shetland Channel was characterised by more or less continuous subsidence dominated throughout the Cenozoic. During the Eocene, sediments deposited in the Faroe–Shetland Channel was mostly derived from a source area on the British shelf.  相似文献   
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