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Jägerbrand, A., Antonson, H. & Ahlström, C. (2018). Speed reduction effects over distance of animal-vehicle collision countermeasures: a driving simulator study. European Transport Research Review, 10(2), Article ID 40.
Open this publication in new window or tab >>Speed reduction effects over distance of animal-vehicle collision countermeasures: a driving simulator study
2018 (English)In: European Transport Research Review, ISSN 1867-0717, E-ISSN 1866-8887, Vol. 10, no 2, article id 40Article in journal (Refereed) Published
Abstract [en]

Purpose: This study examined if speed reduction effects from animal-vehicle collision (AVC) countermeasures are merely local or do extend to a wider area, and what implications the results have on road planning practice regarding AVCs.

Methods: Twenty-five drivers drove repeatedly on a 9-km long road stretch in a high-fidelity driving simulator. The development of vehicle speed in the surrounding of an automatic speed camera, a wildlife warning sign and a radio message, were investigated in a full factorial within-subject experiment. The factors wildlife fence (with/without) and forest (dense/open landscape) were also included.

Results: The radio warning message had the largest influence on vehicle speed with a speed reduction of 8 km/h that lasted beyond 1 km and 2 km after the implementation. Eighty-eight per cent of the drivers reported being made extra aware of AVC due to the radio message, which was also associated with stress, insecurity and unsafety. The warning sign reduced vehicle speed by 1.5 km/h, but speed reductions were not significantly reduced 1 km after the implementation. Only 8 % of the drivers felt insecure/unsafe after passing the wildlife warning sign, explaining its limited impact on speed. There were no main effects of the automatic speed camera on vehicle speed at longer distances after implementation.

Conclusions: We recommend that AVC countermeasures should be of various design, occur at various segments along the road, and preferably be adaptive and geo-localized to minimize habituation effects on drivers.

Place, publisher, year, edition, pages
Springer Verlag, 2018
Keywords
Animal protection, Speed, Decrease, Accident prevention, Simulator (driving), Driver, Reaction (human)
National Category
Vehicle Engineering
Research subject
30 Road: Highway design, 34 Road: Safety devices; 80 Road: Traffic safety and accidents, 81 Road: Accidents
Identifiers
urn:nbn:se:vti:diva-13240 (URN)10.1186/s12544-018-0314-8 (DOI)2-s2.0-85052734562 (Scopus ID)
Available from: 2018-09-12 Created: 2018-09-12 Last updated: 2019-04-24Bibliographically approved
Folkeson, L., Jägerbrand, A. K. & Genell, A. (2017). State of preparedness for climate change adaptation in operations and maintenance of transport infrastructure in eight Swedish municipalities. Linköping: Statens väg- och transportforskningsinstitut
Open this publication in new window or tab >>State of preparedness for climate change adaptation in operations and maintenance of transport infrastructure in eight Swedish municipalities
2017 (English)Report (Other academic)
Alternative title[sv]
Åtta kommuners beredskap för att anpassa drift och underhåll av transportinfrastruktur till klimatförändringarna
Abstract [en]

This study analysed the preparedness for climate change adaptation (CCA) of transport infrastructure in eight municipalities in Sweden. The study focused on municipal officials’ role in organizing and implementing CCA measures. The interviews were done in 2011. Many respondents confused CCA with climate change mitigation. Three of the municipalities had performed vulnerability analyses but apart from that, well-documented decision support in long-term adaptation was largely lacking. Adaptation measures were often based on day-to-day problems and recently experienced weather incidents. Strategic work with long-term CCA seemed to be largely lacking. The placing of the responsibility for CCA in the municipal organization was often unclear. Six of the respondents found there were no actual hindrances to their work with CCA and no conflicts with other municipal aims. However, several responses indicated budgetary competition with environmental aims or other societal strivings. The planning and implementation of CCA measures seemed to be highly dependent on individual officials, their engagement, their passivity/activity regarding this issue, their defined responsibility and the boundaries for their current position in the municipality organization. 

Abstract [sv]

I denna studie analyserades beredskapen för transportsystemets anpassning till klimatförändring i åtta svenska kommuner. Studien fokuserade på kommunala tjänstemäns roll i arbetet med att organisera och genomföra åtgärder för klimatanpassning. Intervjuerna genomfördes 2011. Många av de intervjuade blandade samman klimatanpassning med åtgärder mot klimatförändring. Tre av kommunerna hade utfört sårbarhetsanalyser, men väldokumenterade beslutsstöd för anpassningsåtgärder saknades i hög grad. Där åtgärder genomförts, var de ofta baserade på dagliga problem och erfarenheter från nyligen inträffade väderincidenter. Strategiskt arbete med klimatanpassning verkade i stort sett saknas. Ansvaret för klimatanpassning var ofta oklart. Sex av de intervjuade angav att det inte fanns några egentliga hinder för deras arbete med klimatanpassning eller konflikter med andra kommunala intressen. Flera svar angav dock budgetkonkurrens med kommunala prioriteringar inriktade mot miljö eller andra samhällsintressen. Såväl de intervjuades kunskaper som planeringen och genomförandet av klimatanpassningsåtgärder verkade vara starkt beroende av enskilda tjänstemän och deras engagemang samt definition och avgränsning av deras ansvarsområden inom organisationen.

Place, publisher, year, edition, pages
Linköping: Statens väg- och transportforskningsinstitut, 2017. p. 36
Series
VTI rapport, ISSN 0347-6030 ; 924A
Keywords
Climate change, Adaptation (gen), Local authority, Planning
National Category
Public Administration Studies
Research subject
10 Road: Transport, society, policy and planning, 15 Road: Environment
Identifiers
urn:nbn:se:vti:diva-11895 (URN)
Projects
Planering och beslutsprocesser för klimatanpassning av drift och underhåll
Available from: 2017-07-03 Created: 2017-07-03 Last updated: 2019-05-14Bibliographically approved
Ali, A., Molau, U., Bai, Y., Jägerbrand, A. K. & Alatalo, J. M. (2016). Diversity-productivity dependent resistance of an alpine plant community to different climate change scenarios. Ecological research, 31(6), 935-945
Open this publication in new window or tab >>Diversity-productivity dependent resistance of an alpine plant community to different climate change scenarios
Show others...
2016 (English)In: Ecological research, ISSN 0912-3814, E-ISSN 1440-1703, Vol. 31, no 6, p. 935-945Article in journal (Refereed) Published
Abstract [en]

Here we report from a experiment imposing different warming scenarios [control with ambient temperature, constant level of moderate warming for 3 years, stepwise increase in warming for 3 years, and one season of high level warming (pulse) simulating an extreme summer event] on an alpine ecosystem to study the impact on species diversity–biomass relationship, and community resistance in terms of biomass production.

Multiple linear mixed models indicate that experimental years had stronger influence on biomass than warming scenarios and species diversity. Species diversity and biomass had almost humpback relationships under different warming scenarios over different experimental years. There was generally a negative diversity–biomass relationship, implying that a positive diversity–biomass relationship was not the case.

The application of different warming scenarios did not change this tendency. The change in community resistance to all warming scenarios was generally negatively correlated with increasing species diversity, the strength of the correlation varying both between treatments and between years within treatments. The strong effect of experimental years was consistent with the notion that niche complementarity effects increase over time, and hence, higher biomass productivity over experimental years. The strongest negative relationship was found in the first year of the pulse treatment, indicating that the community had weak resistance to an extreme event of one season of abnormally warm climate.

Biomass production started recovering during the two subsequent years. Contrasting biomass-related resistance emerged in the different treatments, indicating that micro sites within the same plant community may differ in their resistance to different warming scenarios.

Keywords
Vegetation, Climate change
National Category
Ecology
Research subject
SAB, U Science
Identifiers
urn:nbn:se:vti:diva-10993 (URN)10.1007/s11284-016-1403-6 (DOI)2-s2.0-84990831312 (Scopus ID)
Available from: 2016-11-17 Created: 2016-11-03 Last updated: 2017-11-29Bibliographically approved
Jägerbrand, A. & Antonson, H. (2016). Driving behaviour responses to a moose encounter, automatic speed camera, wildlife warning sign and radio message determined in a factorial simulator study. Accident Analysis and Prevention, 86, 229-238
Open this publication in new window or tab >>Driving behaviour responses to a moose encounter, automatic speed camera, wildlife warning sign and radio message determined in a factorial simulator study
2016 (English)In: Accident Analysis and Prevention, ISSN 0001-4575, E-ISSN 1879-2057, Vol. 86, p. 229-238Article in journal (Refereed) Published
Abstract [en]

In a driving simulator study, driving behaviour responses (speed and deceleration) to encountering a moose, automatic speed camera, wildlife warning sign and radio message, with or without a wildlife fence and in dense forest or open landscape, were analysed. The study consisted of a factorial experiment that examined responses to factors singly and in combination over 9-km road stretches driven eight times by 25 participants (10 men, 15 women). The aims were to: determine the most effective animal–vehicle collision (AVC) countermeasures in reducing vehicle speed and test whether these are more effective in combination for reducing vehicle speed; identify the most effective countermeasures on encountering moose; and determine whether the driving responses to AVC countermeasures are affected by the presence of wildlife fences and landscape characteristics. The AVC countermeasures that proved most effective in reducing vehicle speed were a wildlife warning sign and radio message, while automatic speed cameras had a speed-increasing effect. There were no statistically significant interactions between different countermeasures and moose encounters. However, there was a tendency for a stronger speed-reducing effect from the radio message warning and from a combination of a radio message and wildlife warning sign in velocity profiles covering longer driving distances than the statistical tests. Encountering a moose during the drive had the overall strongest speed-reducing effect and gave the strongest deceleration, indicating that moose decoys or moose artwork might be useful as speed-reducing countermeasures. Furthermore, drivers reduced speed earlier on encountering a moose in open landscape and had lower velocity when driving past it. The presence of a wildlife fence on encountering the moose resulted in smaller deceleration.

Keywords
Simulator (driving), Driver, Behaviour, Wildlife crossing, Animal, Camera, Surveillance, Warning, Radio, Message, Landscape
National Category
Applied Psychology Fish and Wildlife Management
Research subject
80 Road: Traffic safety and accidents, 841 Road: Road user behaviour
Identifiers
urn:nbn:se:vti:diva-8219 (URN)10.1016/j.aap.2015.11.004 (DOI)000367105600026 ()26600095 (PubMedID)2-s2.0-84947557382 (Scopus ID)
Funder
Swedish Environmental Protection Agency, 802-0224-09
Available from: 2015-11-19 Created: 2015-11-19 Last updated: 2018-01-10Bibliographically approved
Jägerbrand, A. K. & Sjöbergh, J. (2016). Effects of weather conditions, light conditions, and road lighting on vehicle speed. SpringerPlus, 5(1), Article ID 505.
Open this publication in new window or tab >>Effects of weather conditions, light conditions, and road lighting on vehicle speed
2016 (English)In: SpringerPlus, E-ISSN 2193-1801, Vol. 5, no 1, article id 505Article in journal (Refereed) Published
Abstract [en]

Light conditions are known to affect the number of vehicle accidents and fatalities but the relationship between light conditions and vehicle speed is not fully understood. This study examined whether vehicle speed on roads is higher in daylight and under road lighting than in darkness, and determined the combined effects of light conditions, posted speed limit and weather conditions on driving speed. The vehicle speed of passenger cars in different light conditions (daylight, twilight, darkness, artificial light) and different weather conditions (clear weather, rain, snow) was determined using traffic and weather data collected on an hourly basis for approximately 2 years (1 September 2012–31 May 2014) at 25 locations in Sweden (17 with road lighting and eight without). In total, the data included almost 60 million vehicle passes. The data were cleaned by removing June, July, and August, which have different traffic patterns than the rest of the year. Only data from the periods 10:00 A.M.–04:00 P.M. and 06:00 P.M.–10:00 P.M. were used, to remove traffic during rush hour and at night. Multivariate adaptive regression splines was used to evaluate the overall influence of independent variables on vehicle speed and nonparametric statistical testing was applied to test for speed differences between dark–daylight, dark–twilight, and twilight–daylight, on roads with and without road lighting. The results show that vehicle speed in general depends on several independent variables. Analyses of vehicle speed and speed differences between daylight, twilight and darkness, with and without road lighting, did not reveal any differences attributable to light conditions. However, vehicle speed decreased due to rain or snow and the decrease was higher on roads without road lighting than on roads with lighting. These results suggest that the strong association between traffic accidents and darkness or low light conditions could be explained by drivers failing to adjust their speed to the reduced visibility in dark conditions.

Keywords
Weather, Lighting (street), Day, Night, Dusk, Impact study, Speed
National Category
Vehicle Engineering Infrastructure Engineering
Research subject
30 Road: Highway design, 34 Road: Safety devices; 80 Road: Traffic safety and accidents, 841 Road: Road user behaviour
Identifiers
urn:nbn:se:vti:diva-10609 (URN)10.1186/s40064-016-2124-6 (DOI)2-s2.0-84964310888 (Scopus ID)
Available from: 2016-05-10 Created: 2016-05-10 Last updated: 2017-11-30Bibliographically approved
Alatalo, J. M., Jägerbrand, A. K. & Molau, U. (2016). Impacts of different climate change regimes and extreme climatic events on an alpine meadow community. Scientific Reports, 6, Article ID 21720.
Open this publication in new window or tab >>Impacts of different climate change regimes and extreme climatic events on an alpine meadow community
2016 (English)In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 6, article id 21720Article in journal (Refereed) Published
Abstract [en]

Climate variability is expected to increase in future but there exist very few experimental studies that apply different warming regimes on plant communities over several years. We studied an alpine meadow community under three warming regimes over three years. Treatments consisted of (a) a constant level of warming with open-top chambers (ca. 1.9 °C above ambient), (b) yearly stepwise increases in warming (increases of ca. 1.0, 1.9 and 3.5 °C), and (c) pulse warming, a single first-year pulse event of warming (increase of ca. 3.5 °C). Pulse warming and stepwise warming was hypothesised to cause distinct first-year and third-year effects, respectively. We found support for both hypotheses; however, the responses varied among measurement levels (whole community, canopy, bottom layer, and plant functional groups), treatments, and time. Our study revealed complex responses of the alpine plant community to the different experimentally imposed climate warming regimes. Plant cover, height and biomass frequently responded distinctly to the constant level of warming, the stepwise increase in warming and the extreme pulse-warming event. Notably, we found that stepwise warming had an accumulating effect on biomass, the responses to the different warming regimes varied among functional groups, and the short-term perturbations had negative effect on species richness and diversity.

Keywords
Climate change, Vegetation
National Category
Climate Research
Research subject
SAB, Uh Environmental protection and nature conservation
Identifiers
urn:nbn:se:vti:diva-10114 (URN)10.1038/srep21720 (DOI)000370344700001 ()26888225 (PubMedID)2-s2.0-84959036557 (Scopus ID)
Available from: 2016-03-16 Created: 2016-03-16 Last updated: 2017-11-30Bibliographically approved
Jägerbrand, A. K. (2016). LED (Light-Emitting Diode) road lighting in practice: An evaluation of compliance with regulations and improvements for further energy savings. Energies, 9(5), Article ID 357.
Open this publication in new window or tab >>LED (Light-Emitting Diode) road lighting in practice: An evaluation of compliance with regulations and improvements for further energy savings
2016 (English)In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 9, no 5, article id 357Article in journal (Refereed) Published
Abstract [en]

Light-emitting diode (LED) road lighting has been widely implemented in recent years, but few studies have evaluated its performance after installation. This study investigated whether LED road lighting complies with minimum regulations in terms of traffic safety and whether improvements for energy efficiency are possible. Average road surface luminance (L), overall luminance uniformity (U0), longitudinal luminance uniformity (U1), power density (PD) and normalised power density (PN) were evaluated for 14 roads (seven designed for vehicular traffic and seven for pedestrians and bicycles). Energy savings were calculated as the percentage reduction to the minimum level of the existing lighting class or a lower lighting class and by applying a dimming schedule. The results showed that LED road lighting for vehicular traffic roads generally fulfilled the requirements, whereas that for pedestrian and bicycle roads generally corresponded to the lowest lighting class for L, and often did not meet the statutory requirements for U0 and UI. By adapting lighting levels to the minimum requirement of the existing lighting class or by dropping to a lower lighting class, vehicular traffic roads could save 6%-35% on L to lighting class M5 and 23%-61% on L to lighting class M6. A dimming schedule could lead to energy savings of 49%. There is little potential for savings on pedestrian and bicycle roads, except by implementing a dimming schedule. Thus, in general, for vehicular, pedestrian and bicycle roads, a dimming schedule can save more energy than can be achieved in general by reducing lighting class. Furthermore, since a dimming schedule can be adjusted to traffic intensity, any potential risk of compromising traffic safety is minimised.

Keywords
Light emitting diode, Luminance, Light intensity, Energy efficiency, Highway, Cycle track
National Category
Infrastructure Engineering
Research subject
30 Road: Highway design, 34 Road: Safety devices
Identifiers
urn:nbn:se:vti:diva-10682 (URN)10.3390/en9050357 (DOI)2-s2.0-84968845866 (Scopus ID)
Available from: 2016-06-08 Created: 2016-06-08 Last updated: 2017-11-30Bibliographically approved
Jägerbrand, A. & Kudo, G. (2016). Short-term responses in maximum quantum yield of PSII (Fv/Fm) to ex situ temperature treatment of populations of bryophytes originating from different sites in Hokkaido, Northern Japan. Plants, 5(2), 455-465
Open this publication in new window or tab >>Short-term responses in maximum quantum yield of PSII (Fv/Fm) to ex situ temperature treatment of populations of bryophytes originating from different sites in Hokkaido, Northern Japan
2016 (English)In: Plants, ISSN 2223-7747, Vol. 5, no 2, p. 455-465Article in journal (Refereed) Published
Abstract [en]

There is limited knowledge available on the thermal acclimation processes for bryophytes, especially when considering variation between populations or sites. This study investigated whether short-term ex situ thermal acclimation of different populations showed patterns of site dependency and whether the maximum quantum yield of PSII (Fv/Fm) could be used as an indicator of adaptation or temperature stress in two bryophyte species: Pleurozium schreberi (Willd. ex Brid.) Mitt. and Racomitrium lanuginosum (Hedw.) Brid.

We sought to test the hypothesis that differences in the ability to acclimate to short-term temperature treatment would be revealed as differences in photosystem II maximum yield (Fv/Fm). Thermal treatments were applied to samples from 12 and 11 populations during 12 or 13 days in growth chambers and comprised: (1) 10/5 °C; (2) 20/10 °C; (3) 25/15 °C; (4) 30/20 °C (12 hours day/night temperature).

In Pleurozium schreberi, there were no significant site-dependent differences before or after the experiment, while site dependencies were clearly shown in Racomitrium lanuginosum throughout the study. Fv/Fm in Pleurozium schreberi decreased at the highest and lowest temperature treatments, which can be interpreted as a stress response, but no similar trends were shown by Racomitrium lanuginosum.

Keywords
Vegetation, Temperature
National Category
Ecology
Research subject
SAB, U Science
Identifiers
urn:nbn:se:vti:diva-11467 (URN)10.3390/plants5020022 (DOI)2-s2.0-85005950328 (Scopus ID)
Available from: 2017-01-16 Created: 2017-01-16 Last updated: 2017-01-24Bibliographically approved
During, H. ., Verduyn, B. & Jägerbrand, A. K. (2015). Biomechanical properties of the terrestrial mosses Pleurozium schreberi (Brid.) Mitt. and Pogonatum japonicum Sull. & Lesq. along altitudinal gradients in northern Japan. Arctoa: A Journal of Briology, 24, 375-381
Open this publication in new window or tab >>Biomechanical properties of the terrestrial mosses Pleurozium schreberi (Brid.) Mitt. and Pogonatum japonicum Sull. & Lesq. along altitudinal gradients in northern Japan
2015 (English)In: Arctoa: A Journal of Briology, ISSN 0131-1379, Vol. 24, p. 375-381Article in journal (Refereed) Published
Abstract [en]

Altitudinal gradients along mountain slopes provide valuable opportunities to study variation in plant traits in response to changes in environmental conditions along such  gradients. This study focused on biomechanical traits of two moss species, the more or less horizontally growing Pleurozium schreberi and the erect-growing Pogonatum japonicum, along altitudinal gradients on two mountains in Hokkaido, northern Japan.

We measured stem diameter in two directions to determine the second moment of area I, used three-point bending tests with free stem ends to determine the slope of the force-deflection curve dF/dx, and used these data to calculate Young’s modulus and flexural rigidity of the stems. Both species showed much variation in all traits among replicates in the samples at each altitude. Environmental variation associated with altitude had more effect on the biomechanical traits of P. japonicum than on those of P. schreberi. Stems of P. japonicum were thicker (larger I) than those of P. schreberi and had a larger Young’s modulus and flexural rigidity. Stems tended to become thinner (lower second moment of area) and less rigid (lower flexural rigidity) at increasing altitude in both species.

Place, publisher, year, edition, pages
KMK Scientific Press Ltd., 2015
Keywords
Vegetation, Mountain, Gradients
National Category
Ecology
Research subject
SAB, U Science
Identifiers
urn:nbn:se:vti:diva-8250 (URN)10.15298/arctoa.24.30 (DOI)
Available from: 2015-11-30 Created: 2015-11-30 Last updated: 2017-12-01Bibliographically approved
Alatalo, J. M., Jägerbrand, A. & Čuchta, P. (2015). Collembola at three alpine subarctic sites resistant to twenty years of experimental warming. Scientific Reports, 5, Article ID 18161.
Open this publication in new window or tab >>Collembola at three alpine subarctic sites resistant to twenty years of experimental warming
2015 (English)In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 5, article id 18161Article in journal (Refereed) Published
Abstract [en]

This study examined the effects of micro-scale, site and 19 and 21 years of experimental warming on Collembola in three contrasting alpine subarctic plant communities (poor heath, rich meadow, wet meadow). Unexpectedly, experimental long-term warming had no significant effect on species richness, effective number of species, total abundance or abundance of any Collembola species. There were micro-scale effects on species richness, total abundance, and abundance of 10 of 35 species identified. Site had significant effect on effective number of species, and abundance of six species, with abundance patterns differing between sites. Site and long-term warming gave non-significant trends in species richness.

The highest species richness was observed in poor heath, but mean species richness tended to be highest in rich meadow and lowest in wet meadow. Warming showed a tendency for a negative impact on species richness. This long-term warming experiment across three contrasting sites revealed that Collembola is capable of high resistance to climate change. We demonstrated that micro-scale and site effects are the main controlling factors for Collembola abundance in high alpine subarctic environments. Thus local heterogeneity is likely important for soil fauna composition and may play a crucial role in buffering Collembola against future climate change.

Keywords
Vegetation, Global warming
National Category
Ecology
Research subject
SAB, U Science
Identifiers
urn:nbn:se:vti:diva-8273 (URN)10.1038/srep18161 (DOI)
Available from: 2015-12-16 Created: 2015-12-16 Last updated: 2017-12-01Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0001-5322-9827

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