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1.
In most fisheries catch per unit effort shows significant seasonal and spatial variation. Traditionally, i.e. when vessels are free to choose their harvesting strategy, 80% of the Norwegian cod is landed during the winter in a limited geographical area. To alter the seasonal and spatial supply of cod to the fish processing industry, rural community quotas were introduced. In this paper, we develop a model to predict how different vessels will adapt to the quotas introduced. The hypotheses developed are mostly confirmed in an empirical study. Theoretical, methodological, and managerial implications of the findings are discussed. 相似文献
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3.
Øystein Dalland 《Geoforum》1983,14(2):193-203
This paper explores the historical, geographical and human ecology aspects of an extreme conflict between development and conservation in northern Scandinavia. Development of hydro-power projects not only affects the physical environment but also conflicts with the culture of a distinct ethnic community, the Sami Lapps. Over one hundred power and mining projects have now been constructed in Sami territory, the cumulative effects of which have focused opposition to the Alta—Kautokeino Waterway. The long- and short-term origins of the conflict are analysed in the light of Sami ecology and Norwegian administrative principles. How the Sami ecology has affected the national frontiers and recent resource management issues are described. Finally, the importance of environmental protests and public hearings in the resolution of fundamental resource/land use conflicts is discussed. The author concludes that the basic aspects of land use conflict may be analysed by using a symbiotic ecology model and applying this to technical human activities. 相似文献
4.
Sverre Solberg Norbert Schmidbauer Arne Semb Frode Stordal Øystein Hov 《Journal of Atmospheric Chemistry》1996,23(3):301-332
Several years of measurements of ozone, hydrocarbons, sulphate and meteorological parameters from Spitsbergen in the Norwegian Arctic are presented. Most of the measurements were taken on the Zeppelin Mountain at an altitude of 474 m a.s.l. The focus is the episodes of ozone depletion in the lower troposphere in spring, which are studied in a climatological way. Episodes of very low ozone concentrations are a common feature on the Zeppelin Mountain in spring. The low ozone episodes were observed from late March to the beginning of June. When the effect of transport direction was subtracted, the frequenty of the low ozone episodes was found to peak in the beginning of May, possibly reflecting the seasonal cycle in the actual depletion process. Analyses based on trajectory calculations show that most of the episodes occurred when the air masses were transported from W-N. Ozone soundings show that the ozone depletion may extend from the surface and up to 3–4 km altitude. The episodes were associated with a cold boundary layer beneath a thermally stable layer, suppressing mixing with the free troposphere. The concentration of several individual hydrocarbons was much lower during episodes of low ozone than for the average conditions. The change in concentration ratio between the hydrocarbons was in qualitative agreement with oxidation of hydrocarbons by Br and Cl atoms rather than by OH radicals. 相似文献
5.
Two years of individual nonmethane hydrocarbon (NMHC) measurements at a rural site close to the south coast of Norway show that there was a distinct annual cycle with a late winter maximum and late summer minimum in the slowly reacting NMHCs acetylene, ethane, propane and i- and n-butane. The average January—March concentrations were a factor 2–4 higher than the July-September concentrations. Also ethene, propene and the pentanes show a similar annual cycle, but the individual scatter in the measurements in particular of propene, is large. The highest concentrations of NMHC were found in winter for easterly transport on a regional scale (out to 1500 km from the site), and for southeasterly transport in the summer. 相似文献
6.
High resolution spectral observations between 500 MHz and 550 MHz on 1972 October 25, revealed an emission event of special interest. The main feature was bursts with a single frequency duration of about 0.09 s and with a bandwidth of the same order of magnitude as the band covered by the spectrograph. The bursts occurred in showers' which lasted for one or two minutes and which were separated by quiet intervals of roughly the same length. Frequently the activity assumed a periodic nature. Periods between 0.1 s and 0.3 s were found. The most remarkable feature of the records was a very large number of bursts with the same duration as the wide band bursts, but showing a bandwidth of a mere 1–2 MHz.The wide band bursts may be plasma waves excited by proton streams trapped in coronal magnetic fields and the narrow band bursts may possibly be explained as perpendicular electrostatic electron cyclotron waves. 相似文献
7.
Herbjørn Presthus Heggen John Inge Svendsen Jan Mangerud Øystein S. Lohne 《Boreas: An International Journal of Quaternary Research》2012,41(4):527-545
Recently, the sediment stratigraphy and geochronology of the well‐known Palaeolithic site Byzovaya in northern Russia were investigated. New technological analyses of the artefacts suggest a Middle Palaeolithic Mousterian culture, and occupation by Neanderthals, not Modern humans as previously thought. We present here a new and detailed documentation of the stratigraphy, including the geological context of the artefacts and faunal remains. From sedimentological criteria we confidently interpret the find‐bearing strata as debris‐flow deposits, covered by aeolian sediments. The chronology is based on radiocarbon and luminescence (OSL) dates from the find‐bearing and overlying strata. The results are utilized to reconstruct the geological history at the excavation area. The stratigraphy varies considerably across the excavation area. The most intact and undisturbed part of the sequence was found inside the most recent Excavation II. In this part the artefacts and bones appear to have been permanently sealed and protected by aeolian sand. The older Excavation I shows a more complicated stratigraphy, as the finds may have been temporarily exposed during the early Holocene owing to ravine incision and slumping activity. The individual radiocarbon dates that were collected from different parts of the site and from various stratigraphic positions are re‐investigated in this study. By using Bayesian statistics the conclusion is that the site was occupied during a restricted period around 30.6–34.7 ka. A series of partly unpublished OSL dates of coversand from different sites demonstrates a regional aeolian signal during the Lateglacial in northern Russia, 15–14 ka. 相似文献
8.
Björn S. Frengstad Kaj Lax Timo Tarvainen Øystein Jæger Börge J. Wigum 《Journal of Geochemical Exploration》2010
Twenty-two bottled mineral and spring waters from Norway, Sweden, Finland and Iceland have been analysed for 71 inorganic chemical parameters with low detection limits as a subset of a large European survey of bottled groundwater chemistry (N = 884). The Nordic bottled groundwaters comprise mainly Ca–Na–HCO3–Cl water types, but more distinct Ca–HCO3, Na HCO3 and Na–Cl water types are also offered. The distributions for most elements fall between groundwater from Fennoscandian Quaternary unconsolidated aquifers and groundwater from Norwegian crystalline bedrock boreholes. Treated tap waters have slightly lower median values for many parameters, but elements associated with plumbing have significantly higher concentrations in tap waters than in bottled waters. The small dataset is able to show that excessive fluoride and uranium contents are potential drinking water problems in Fennoscandia. Nitrate and arsenic displayed low to moderate concentrations, but the number of samples from Finland and Northern Sweden was too low to detect that elevated concentrations of arsenic occur in bedrock boreholes in some regions. The data shows clearly that water sold in plastic bottles is contaminated with antimony. Antimony is toxic and suspected to be carcinogenic, but the levels are well below the EU drinking water limit. The study does not provide any health-based arguments for buying bottled mineral and spring waters for those who are served with drinking water from public waterworks. Drinking water from crystalline bedrock aquifers should be analysed. In case of elevated concentrations of fluoride, uranium or arsenic, most bottled waters, but not all, will be better alternatives when treatment of the well water is not practicable. 相似文献
9.
Towards a 4D topographic view of the Norwegian sea margin 总被引:1,自引:1,他引:0
Morten Smelror John Dehls Jrg Ebbing Eiliv Larsen Erik R. Lundin
ystein Nordgulen Per Terje Osmundsen Odleiv Olesen Dag Ottesen Christophe Pascal Thomas F. Redfield Leif Rise 《Global and Planetary Change》2007,58(1-4):382
The present-day topography/bathymetry of the Norwegian mainland and passive margin is a product of complex interactions between large-scale tectonomagmatic and climatic processes that can be traced back in time to the Late Silurian Caledonian Orogeny. The isostatic balance of the crust and lithosphere was clearly influenced by orogenic thickening during the Caledonian Orogeny, but was soon affected by post-orogenic collapse including overprinting of the mountain root, and was subsequently affected by a number of discrete extensional events eventually leading to continental break-up in Early Eocene time. In the mid-Jurassic the land areas experienced deep erosion in the warm and humid climate, forming a regional paleic surface. Rift episodes in the Late Jurassic and Early Cretaceous, with differential uplift along major fault zones, led to more pronounced topographic contrasts during the Cretaceous, and thick sequences of clastic sediments accumulated in the subsiding basins on the shelf. Following renewed extension in the Late Cretaceous, a new paleic surface developed in the Paleocene. Following break-up the margin has largely subsided thermally, but several Cenozoic shortening events have generated positive contraction structures. On the western side of the on-shore drainage divide, deeper erosion took place along pre-existing weakness zones, creating the template of the present day valleys and fjords. In the Neogene the mainland and large portions of the Barents Sea were uplifted. It appears that this uplift permitted ice caps to nucleate and accumulate during the Late Pliocene northern hemisphere climatic deterioration. The Late Pliocene to Pleistocene glacial erosion caused huge sediment aprons to be shed on to the Norwegian Sea and Barents Sea margins. Upon removal of the ice load the landmass adjusted isostatically, and this still continues today. 相似文献
10.
John Inge Svendsen Lars Martin B. Frseth Richard Gyllencreutz Haflidi Haflidason Mona Henriksen Morten N. Hovland
ystein S. Lohne Jan Mangerud Dmitry Nazarov Carl Regnll Joerg M. Schaefer 《Boreas: An International Journal of Quaternary Research》2019,48(2):407-431
Our knowledge about the glaciation history in the Russian Arctic has to a large extent been based on geomorphological mapping supplemented by studies of short stratigraphical sequences found in exposed sections. Here we present new geochronological data from the Polar Ural Mountains along with a high‐resolution sediment record from Bolshoye Shchuchye, the largest and deepest lake in the mountain range. Seismic profiles show that the lake contains a 160‐m‐thick sequence of unconsolidated lacustrine sediments. A well‐dated 24‐m‐long core from the southern end of the lake spans the last 24 cal. ka. From downward extrapolation of sedimentation rates we estimate that sedimentation started about 50–60 ka ago, most likely just after a large glacier had eroded older sediments from the basin. Terrestrial cosmogenic nuclide (TCN) exposure dating (10Be) of boulders and Optically Stimulated Luminescence (OSL) dating of sediments indicate that this part of the Ural Mountains was last covered by a coherent ice‐field complex during Marine Isotope Stage (MIS) 4. A regrowth of the glaciers took place during a late stage of MIS 3, but the central valleys remained ice free until the present. The presence of small‐ and medium‐sized glaciers during MIS 2 is reflected by a sequence of glacial varves and a high sedimentation rate in the lake basin and likewise from 10Be dating of glacial boulders. The maximum extent of the mountain glaciers during MIS 2 was attained prior to 24 cal. ka BP. Some small present‐day glaciers, which are now disappearing completely due to climate warming, were only slightly larger during the Last Glacial Maximum (LGM) as compared to AD 1953. A marked decrease in sedimentation rate around 18–17 cal. ka BP indicates that the glaciers then became smaller and probably disappeared altogether around 15–14 cal. ka BP. 相似文献