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41.
ABSTRACT

The objective of the article is to show how the demonstration project and battery ferry Ampere has contributed to a greening of public ferry procurement in Norway. Building on theories on demonstration projects in transition studies and institutional work, the author argues for a more integrated focus than hitherto on the dynamic interplay of materiality, organization, and discourse in demonstration projects, and how the agency of actor networks and the materiality connected to demonstration projects can affect institutional change accompanying transition processes. This is done by conceptualizing Ampere as a ‘performing project’: a complex of discursive and organizational strategies of framing and lobbying deployed by the actor networks connected to it and its materiality. Methodically, the author draws on semi-structured interviews and document analysis. The results suggest that Ampere’s ‘performance’ has contributed to changes in national and regional ferry procurement practices and been vital for an emerging maritime battery niche.  相似文献   
42.
43.
ABSTRACT

Efficiency in agricultural food production has long been in focus and this has affected the spatial structure of agricultural land use. One outcome has been extensive criticism based on a wide range of negative consequences, such as for biodiversity, accessibility, cultural heritage, and aesthetics. In line with the European Landscape Convention (ELC), management of people’s everyday landscapes is important. In Norway, agricultural landscapes are the ‘everyday landscape’ for a large proportion of the population. The aim of the article is to contribute to the understanding of landscape changes perceived as positive or negative by the inhabitants. The authors focused on grain-crop dominated landscapes and the impact of smaller non-crop elements on people’s landscape preferences. They administered a photo-based questionnaire using manipulated photos to assess preferences for different agricultural landscapes. Additionally, people’s perceived objectives for the agricultural sector and agriculture’s primary functions were assessed. The results documented positive perceptions of added landscape elements and that people were both aware of and agreed on the multifunctional role of agriculture. The authors conclude that if the public’s preferences are to be taken into consideration, such as during policymaking, it is important to maintain various landscape elements in the large-scale grain field landscapes of Norway.  相似文献   
44.
The Arctic Mediterranean is the ocean area north of the Greenland-Scotland Ridge. Exchanges between this region and the North Atlantic both provide the main source for production of North Atlantic Deep Water and supply heat and salt to the northern oceans. The exchange occurs through several gaps in the ridge; in terms of volume flux the Iceland-Scotland Gap is the most important one as it carries more than half the total, with approximately three quarters of the total inflow and one third of the total outflow. The Nordic WOCE observational system was initiated to monitor the exchanges through this gap and it has provided data that allow estimates of typical fluxes and their seasonal variation. The flux measurements show that most of the Atlantic inflow to the Arctic Mediterranean returns as overflow and hence the processes forming intermediate and deep waters in the Arctic Mediterranean are the main forcing mechanism for the Atlantic inflow. The inflow between Iceland and Scotland seems to be a maximum in late winter while the Faroe Bank Channel overflow is strongest in late summer. Using the results from the Nordic WOCE system it has been possible to interpret historical observations from Ocean Weather Ship Station M and conclude that the flux of the Faroe Bank Channel overflow decreased in magnitude from 1950 to 2000.  相似文献   
45.
Using synchronous cultures of the unicellular green alga Chlamydomonas reinhardti, the toxicities of mixtures of Ekofisk crude oil and oil dispersants were measured. Sixteen so-called concentrates and 10 solvent-based dispersants were tested. The dispersing effectiveness of these compounds with respect to the Ekofisk crude oil was also measured. The concentrates were tested undiluted as well as diluted using algal growth medium (2‰ salinity) and artificial sea water (33‰ salinity) as dispersing liquid. The solvent-based compounds were tested in algal medium. For all compounds we found significant correlations between their toxicity and their effectiveness in dispersing the Ekofisk oil, such that the more effective the compound, the more toxic it was.  相似文献   
46.
Hydrographic time series from the northern North Atlantic throughout the 20th century show oscillations in temperature and salinity at more or less regular intervals. The Great Salinity Anomalies described during the 1970s [Dickson, R.R., Meincke, J., Malmberg, S.-A., Lee, A.J., 1988. The “Great Salinity Anomaly” in the North Atlantic, 1968-1982. Progress in Oceanography 20, 103-151.], during the 1980s [Belkin, I.M., Levitus, S., Antonov, J., Malmberg, S.-A., 1998. “Great Salinity Anomalies” in the North Atlantic. Progress in Oceanography 41, 1-68.], and during the 1990s [Belkin, I.M., 2004. Propagation of the “Great Salinity Anomaly” of the 1990s around the northern North Atlantic. Geophysical Research Letters 31(8), L08306, doi:10.1029/2003GL019334.] have distinct amplitudes, and all three of them were interpreted as low salinity anomalies propagating downstream through the anti-clockwise circulation system of the northern North Atlantic Ocean. Further inspection of time series from the Northeast Atlantic and the Northwest Atlantic over the past century shows, however, several other distinct negative anomalies of lesser amplitudes. Additionally, a number of high salinity anomalies can be identified. The present paper analyses further the propagation of the negative and positive anomalies and links them together. It is shown that they have varying speeds of propagation, and that the varying speeds are correlated across the North Atlantic. We propose that varying volume fluxes in and out of the Arctic Basin is the causal mechanism behind the anomaly signals, and that the North Atlantic Oscillation (NAO) partly has influence on the flux variations described. Periods of large decadal-scale amplitudes of the NAO coincide with periods of large decadal-scale oscillation in the marine climate.  相似文献   
47.
Governors always have some image of what they are governing and why, and of what their role is. These images are often implicit. They are not reflected upon or discussed in the governance process, yet they have real consequences because they are acted upon. Interactive governance theory argues that image formation is an integral part of governance and that images are made as explicit as possible to avoid self-fulfilment. Such a process needs to be interactive and flexible to allow exploration of alternatives to existing governing images for the purpose of enhancing the governability of fisheries systems. In this paper, we contrast the classical image of the governing system (top down decision-making pyramid) and of the human-in-nature system (top down trophic pyramid) with alternative images (roses and inverted pyramid, respectively) and discuss the implication that these different images have on fisheries governance.  相似文献   
48.
Many west coastal and northern Norwegian rivers run through deep, confined valleys with permeable layers of glacial and alluvial deposits. Groundwater flows through these permeable layers and enter lakes and rivers as underwater seepage and springs. Groundwater inflow to inland Norwegian rivers may constitute 40–100% of total water discharge during low flow periods in late summer and winter. Juvenile salmonids may take advantage of groundwater upwellings and actively seek out such patches. In regulated rivers groundwater influx may create refuges during low flow or hydropeaking episodes. The importance of groundwater for salmon redd site selection and egg survival is also clear, although less known and documented in regulated rivers.Eggs of Atlantic salmon (Salmo salar) are deposited in redds in river bed gravels lacking fine sediments and with high oxygen levels. Egg development is therefore dependent on the interaction of a number of environmental factors such as groundwater influx, oxygen and temperature. Atlantic salmon in the regulated River Suldalslågen, Western Norway, spawn relatively late compared to other Norwegian rivers, with a peak in early January. Newly emerged fry are found from the end of May to the beginning of June, i.e. “swim up” one month earlier than expected using models for egg and alevin development and river water temperatures. The most plausible explanation is that groundwater has a higher and more stable temperature than surface river water. In field experiments, fertilized salmon eggs were placed in boxes close to natural spawning redds in the river bed at sites influenced and those not influenced by groundwater. A difference of up to 40 days in 50% hatching was found, and “swim up” occurred at the end of May in boxes influenced by groundwater.Preliminary studies have revealed that groundwater also plays an important role in survival of salmon eggs in the River Suldalslågen when dewatered in winter. Eggs placed in boxes in groundwater seepage areas during winter in the dewatered river bed survived even when covered by ice and snow. The survival from fertilization until 30 April, one month before hatching, was 91%, the same survival as found for eggs placed in boxes in the wetted river bed. However, mortality from fertilization to hatching was higher compared to the eggs placed in wetted river bed, 57 and 91% respectively.Groundwater creates a horizontal and vertical mosaic of temperatures in spawning redd areas leading to potentially greater variation in spawning sites, time of hatching and “swim up”. This is likely to increase egg survival during low flow periods in regulated rivers. In conclusion, the interaction between groundwater and surface river water should therefore be considered when managing fish populations in regulated rivers.  相似文献   
49.
The problem of insufficient age-control limits the utilisation of the 8.2 ka BP event for modelling freshwater forcing in climate change studies. High-resolution radiocarbon dates, magnetic susceptibility and lithostratigraphic evidence from a lake sediment core from Nedre Hervavatnet located at Sygnefjell in western Norway provide a record of the early Holocene. We use the method of radiocarbon wiggle-match dating of the lake sediments using the non-linear relationship between the 14C calibration curve and the consecutive accumulation order of the sample series in order to build a high-resolution age-model. The timing and duration of Holocene environmental changes is estimated using 38 AMS radiocarbon dates on terrestrial macrofossils, insects and chironomids covering the time period from 9750 to 1180 cal BP. Chironomids, Salix and Betula leaves produce the most consistent results. Sedimentological and physical properties of the core suggest that three meltwater events with high sedimentation rates are superimposed on a long-term trend with glacier retreat between 9750 and 8000 cal BP. The lake sediment sequence of Nedre Hervavatnet demonstrates the following: only a reliable high-resolution geochronology based on carefully selected terrestrial macrofossils allows the reconstruction of a more refined and complex environmental change history before and during the 8.2 ka event.  相似文献   
50.
Drawing on an EU-funded project titled “Sharing responsibilities in fisheries management” this paper assesses the institutional landscape of fisheries management in a number of European countries, with a particular emphasis on stakeholder involvement in regulatory decision-making. What are their roles and responsibilities in the chain of governance? What are the specific characteristics of each country, and what is similar and what is different as compared with other sectors? Although there is a move towards devolvement and decentralisation in some European countries, there is quite an ambivalence regarding such reforms in other countries. These differences in stakeholder involvement are partly a result of institutional traditions within each country, but also a reflection of how management authorities struggle with the dilemmas pertaining to such reforms of participatory practices. Thus, we argue that even within a reformed fisheries management system that allows greater participation of stakeholder groups, there can hardly be one European model that fits all.  相似文献   
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