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21.
Torbjørn Rundmo Trond Nordfjærn Hilde Hestad Iversen Sigve Oltedal Stig H. Jørgensen 《Safety Science》2011,49(2):226-235
AimsThe core aim of the present study was to examine the role of risk perception in use of private and public modes of transportation. An additional aim was to examine the relative importance of perception of transport risks with risk perception of non-transport factors and also to investigate differences in worry, perceived control of transportation modes, as well as trust in authorities’ risk handling, safety motivation, and attitudes towards transport safety.SampleThe results are based on a mailed self-completion questionnaire survey carried out among a representative sample of the Norwegian public aged from 18 to 65 years (n = 1864). Data collection was carried out during October–December 2008.ResultsPerceived control related to private modes of transportation, knowledge about safety and trust in authorities were found to be significantly different among respondents who often used private modes of transportation compared to those who most often used public modes. It was no significant difference in severity of consequences due to which transport modes that the respondents used most frequently.ConclusionIt may be that conclusions of previous research about the role of consequence judgement for precautionary action and demand for risk reduction are misleading when generalised to decisions about transport mode use. 相似文献
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23.
Winter losses of nitrogen and phosphorus from Italian ryegrass, meadow fescue and white clover in a northern temperate climate 总被引:1,自引:0,他引:1
Ievina Sturite Trond Maukon Henriksen Tor Arvid Breland 《Agriculture, ecosystems & environment》2007,120(2-4):280-290
We have studied to what degree Italian ryegrass (Lolium multiflorum Lam.), white clover (Trifolium repens L.) and meadow fescue (Festuca pratensis L.) are able to preserve nitrogen (N) and phosphorous (P) in shoots and roots from one growing season to the next in a northern temperate climate. Field experiments were performed during four consecutive winters in central southeast Norway (60°42′N, 10°51′E), and N and P in plant biomass were measured in the autumn and in the spring. We also measured the contents of total N, total P and organic carbon (C) in seepage water that percolated through the aboveground plant material. Uptake of N and P in Italian ryegrass and white clover was substantially larger than in meadow fescue. The winter losses varied greatly from year to year, depending on the winter climate. On the average for all three of the plant species, the winter losses of N from aboveground biomass were 6, 35, 68 and 10% in the four experimental years, respectively. The corresponding P losses were 11, 36, 60 and 22%. On the average for all plant species and experimental years, 43 (±12)% (S.E., n = 12) of the N, 34 (±9)% of the P and 4 (±1)% of the C that was lost from the aboveground plant biomass during the winter, was recovered in seepage water, basically as a nutrient pulse in melt water in early spring. The very low C recovery rate in seepage water suggested a considerable microbial growth on lost plant C. Assuming that all un-recovered plant C was consumed by microorganisms not included in measurements of the seepage water, modelling showed that microbial immobilisation theoretically might explain the unexpectedly low recovery rates of N and P. The study was not designed to investigate the possible effects of psychrophilic microbes on N and P cycling. Therefore, it is inconclusive and underlines the need for more knowledge on this matter. 相似文献
24.
Trond Husby Henri L. F. de Groot Marjan W. Hofkes Tatiana Filatova 《Mitigation and Adaptation Strategies for Global Change》2018,23(2):147-168
Human migration is increasingly seen as a promising climate change adaptation and flood risk reduction strategy. The purpose of this paper is to investigate how spatial differences in flood risk, due to differences in flood protection, reduce the mobility of vulnerable households through a credit constraint mechanism. Using an equilibrium model with two households types and endogenous sorting, we show how spatial differences in flood protection lead to clustering of vulnerable households in a risky region, in a real-world setting of common United States (US) flood zones. We find clustering effects of some size for flood zones with return periods of less than 30 years. 相似文献
25.
Edwards DP Woodcock P Edwards FA Larsen TH Hsu WW Benedick S Wilcove DS 《Ecological applications》2012,22(2):561-571
A key driver of rain forest degradation is rampant commercial logging. Reduced-impact logging (RIL) techniques dramatically reduce residual damage to vegetation and soils, and they enhance the long-term economic viability of timber operations when compared to conventionally managed logging enterprises. Consequently, the application of RIL is increasing across the tropics, yet our knowledge of the potential for RIL also to reduce the negative impacts of logging on biodiversity is minimal. We compare the impacts of RIL on birds, leaf-litter ants, and dung beetles during a second logging rotation in Sabah, Borneo, with the impacts of conventional logging (CL) as well as with primary (unlogged) forest. Our study took place 1-8 years after the cessation of logging. The species richness and composition of RIL vs. CL forests were very similar for each taxonomic group. Both RIL and CL differed significantly from unlogged forests in terms of bird and ant species composition (although both retained a large number of the species found in unlogged forests), whereas the composition of dung beetle communities did not differ significantly among forest types. Our results show little difference in biodiversity between RIL and CL over the short-term. However, biodiversity benefits from RIL may accrue over longer time periods after the cessation of logging. We highlight a severe lack of studies investigating this possibility. Moreover, if RIL increases the economic value of selectively logged forests (e.g., via REDD+, a United Nations program: Reducing Emissions from Deforestation and Forest Degradation in Developing Countries), it could help prevent them from being converted to agricultural plantations, which results in a tremendous loss of biodiversity. 相似文献
26.
The present study aimed to investigate differences in risk perception, the demand for risk mitigation, priorities and worry related to transport among the Norwegian public in 2004 and 2008. Age, gender, education, driver licence and number of injuries in transport were controlled for. The comparison was carried out with questionnaire surveys among representative samples of the Norwegian public in 2004 (n = 1730) and 2008 (n = 1864). The results showed that the perceived probabilities of transport accidents decreased, whereas the perceived severity of consequences increased during this period. Both samples estimated higher probabilities of accidents by private means of transport. The demand for risk mitigation and priorities related to transport safety increased significantly in the same period. The 2008 sample also reported more worry regarding accidents by private transport. Results were discussed in relation to transport safety campaigns, safety measures and significant accidents which occurred in this period. 相似文献
27.
Do males and females differ in the feeding of large and small siblings? An experiment with the bluethroat 总被引:3,自引:0,他引:3
Per T. Smiseth Trond Amundsen Lars T. T. Hansen 《Behavioral ecology and sociobiology》1998,42(5):321-328
Males and females have been reported to differ in their feeding of large and small siblings in several species of birds.
According to recent hypotheses, this phenomenon may be related to a sexual conflict over avian hatching patterns. We designed
an experiment to test for the existence of such a sex difference by manipulating nestling size hierarchies of the bluethroat
(Luscinia s. svecica) in two directions; half the broods were “asynchronized” to yield large size-differences within broods and the other half
were “synchronized” to yield small size-differences. In all broods, nestlings were categorized as being either large or small
according to body mass. We recorded male and female food distribution by video early (day 4 after hatching) and late (day
8) in the nestling period. Males and females did not differ in their distribution of food among different-sized nestlings.
With large size-differences, both males and females fed large nestlings nearly twice as often as small ones. In contrast,
when the size-differences were small, food was more evenly distributed among nestlings. Early in the nestling period, males
fed more nestlings during each feeding visit than did females. Our finding that male and female bluethroats do not differ
in the feeding of large and small siblings is in contrast to most previous studies. Variation in costs and benefits to males
and females from feeding different-sized nestlings, and restrictions to parental choice due to nestling interactions, may
explain interspecific variation.
Received: 27 June 1997 / Accepted after revision: 26 January 1998 相似文献
28.
Females in several sexually dimorphic species with conventional sex roles possess ornamental traits that resemble those found
in males. The evolution of such traits, however, is still poorly understood. Bluethroats (Luscinia s. svecica) are socially monogamous, sexually dichromatic passerine birds, in which female throat patch coloration varies from near
absence to near full expression of male-like coloration. A recent study, demonstrating that male bluethroats prefer colourful
females, suggests that female coloration is subject to sexual selection through male choice. However, the benefits males may
gain from mating with colourful females have not yet been identified. In this study we tested the hypothesis that female coloration
signals parental quality (the good-parent hypothesis). During the course of the same day, we recorded female care both in
the presence and the absence of the male mate. The latter was done to eliminate the confounding effect of variable male care
by removing the male temporarily. Female coloration did not correlate with female feeding rates either in the presence or
in the absence of the male. Female feeding rates in the absence and the presence of the male were positively, although weakly,
correlated. Female coloration did not correlate with female ability to compensate for the loss of male care, or with the change
in brood mass during male removal. Therefore, there is no evidence for the good-parent hypothesis to explain female plumage
coloration in bluethroats.
Received: 4 March 1999 / Received in revised form: 14 October 1999 / Accepted: 23 October 1999 相似文献
29.
Helene Amundsen 《Local Environment》2015,20(3):257-276
Changes in a range of interlinked factors, in social, economic, environmental and climatic conditions, require adaptation in many communities. This paper explores how place attachment affects adaptive responses to a changing social context through analysing adaptation in two coastal municipalities in Northern Norway. The main challenge in these municipalities is declining populations and the consequences accompanying this trend, including livelihood uncertainties and decreased provision of public services. This paper discusses the role of place attachment in motivating adaptation to these changes to contribute to a growing body of literature within climate change adaptation on “subjective” (values, culture and place) dimensions. The findings suggest that people are motivated to act based on their emotional connection with place, and the paper argues that place attachment may offer a better starting point for climate change adaptation than an emphasis on climate change impacts. 相似文献
30.
The investigation was carried out from 62°N to 73°N and from 14°E to 11°W in the Norwegian Sea during 19 June-12 July 1997. Regional differences in the phase of the seasonal development of the plankton community were evident, most pronounced across the Arctic front. In the Coastal and eastern Atlantic domains, post-bloom conditions prevailed, characterised by low chlorophyll a (chl a) levels and a phytoplankton assemblage dominated by coccolithophorids and small flagellates. During the study period, egg production rates of Calanus finmarchicus were low (<10 eggs female-1 day-1), older copepodite stages dominated, and the seasonal descent to deeper waters had started. In the Arctic domain, bloom conditions were evident by high chl a levels and a high abundance of large diatoms. Egg production rates were higher (a maximum of 29 eggs female-1 day-1), but the dominance of stages CI-CIII indicated that considerable spawning had already occurred prior to the spring bloom. The seasonal descent had barely started. Both invertebrate and fish predators were most abundant in the Coastal and eastern Atlantic domains, with abundance strongly decreasing north-westwards. No tight relationship between total abundance of invertebrate or fish predators and that of C. finmarchicus was apparent. However, a weak, but significant, relationship between abundance of young stages of chaetognaths and Euchaeta spp. versus young stages of C. finmarchicus was found, indicating that these invertebrate predators develop parallel to the development of the new cohort of C. finmarchicus. In early summer, C. finmarchicus had reached overwintering stages, and had started to accumulate in deeper waters in areas with the highest abundance of horizontally migratory planktivorous fish. 相似文献