| 1. |
- Abelev, Betty, et al.
(författare)
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Measurement of prompt J/psi and beauty hadron production cross sections at mid-rapidity in pp collisions at root s=7 TeV
- 2012
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Ingår i: Journal of High Energy Physics. - 1029-8479. ; :11
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Tidskriftsartikel (refereegranskat)abstract
- The ALICE experiment at the LHC has studied J/psi production at mid-rapidity in pp collisions at root s = 7 TeV through its electron pair decay on a data sample corresponding to an integrated luminosity L-int = 5.6 nb(-1). The fraction of J/psi from the decay of long-lived beauty hadrons was determined for J/psi candidates with transverse momentum p(t) > 1,3 GeV/c and rapidity vertical bar y vertical bar < 0.9. The cross section for prompt J/psi mesons, i.e. directly produced J/psi and prompt decays of heavier charmonium states such as the psi(2S) and chi(c) resonances, is sigma(prompt J/psi) (p(t) > 1.3 GeV/c, vertical bar y vertical bar < 0.9) = 8.3 +/- 0.8(stat.) +/- 1.1 (syst.)(-1.4)(+1.5) (syst. pol.) mu b. The cross section for the production of b-hadrons decaying to J/psi with p(t) > 1.3 GeV/c and vertical bar y vertical bar < 0.9 is a sigma(J/psi <- hB) (p(t) > 1.3 GeV/c, vertical bar y vertical bar < 0.9) = 1.46 +/- 0.38 (stat.)(-0.32)(+0.26) (syst.) mu b. The results are compared to QCD model predictions. The shape of the p(t) and y distributions of b-quarks predicted by perturbative QCD model calculations are used to extrapolate the measured cross section to derive the b (b) over bar pair total cross section and d sigma/dy at mid-rapidity.
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| 2. |
- Abelev, Betty, et al.
(författare)
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Underlying Event measurements in pp collisions at root s=0.9 and 7 TeV with the ALICE experiment at the LHC
- 2012
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Ingår i: Journal of High Energy Physics. - 1029-8479. ; :7
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Tidskriftsartikel (refereegranskat)abstract
- We present measurements of Underlying Event observables in pp collisions at root s = 0 : 9 and 7 TeV. The analysis is performed as a function of the highest charged-particle transverse momentum p(T),L-T in the event. Different regions are defined with respect to the azimuthal direction of the leading (highest transverse momentum) track: Toward, Transverse and Away. The Toward and Away regions collect the fragmentation products of the hardest partonic interaction. The Transverse region is expected to be most sensitive to the Underlying Event activity. The study is performed with charged particles above three different p(T) thresholds: 0.15, 0.5 and 1.0 GeV/c. In the Transverse region we observe an increase in the multiplicity of a factor 2-3 between the lower and higher collision energies, depending on the track p(T) threshold considered. Data are compared to PYTHIA 6.4, PYTHIA 8.1 and PHOJET. On average, all models considered underestimate the multiplicity and summed p(T) in the Transverse region by about 10-30%.
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| 3. |
- Angelstam, Per, et al.
(författare)
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Effects of Land Use Intensification on Avian Predator Assemblages: A Comparison of Landscapes with Different Histories in Northern Europe
- 2019
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Ingår i: Diversity. - : MDPI AG. - 1424-2818. ; 11
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Tidskriftsartikel (refereegranskat)abstract
- Land use and landcover change alter the ability of habitat networks to maintain viable species populations. While their effects on the quality, amount and patterns of landcover patches are commonly studied, how they affect ecological processes, such as predation on focal species remains neglected. This macroecological study tests the hypothesis that predator assemblages are affected by land use intensity linked to different socio-economic contexts. We measured the distribution and abundance of two avian predator groups (generalist corvid birds and specialist raptors), and proxy variables that mirror their food resources, at three spatial scales in northern Europe's West and East. In total, we made 900 survey counts for avian predators and their resources in six landcover strata throughout five landscapes and analyzed their relationships. The abundance of omnivorous corvid birds was associated with the number of anthropogenic food resources. Thus, corvid birds were most common in the urban and agricultural landcovers, and where forest cover was low. Corvid bird abundance, and availability of their resources, increased with increasing land use intensity. Raptors were less abundant than corvid birds and most common in semi-natural grasslands. The number of raptor species increased with decreasing land use intensity. This study shows that the abundance and composition of avian predator species must be understood to maintain functional habitat networks.
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| 4. |
- Angelstam, Per, et al.
(författare)
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Green infrastructure development at European Union's eastern border: Effects of road infrastructure and forest habitat loss
- 2017
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Ingår i: Journal of Environmental Management. - : Elsevier BV. - 0301-4797 .- 1095-8630. ; 193, s. 300-311
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Tidskriftsartikel (refereegranskat)abstract
- The functionality of forest patches and networks as green infrastructure may be affected negatively both by expanding road networks and forestry intensification. We assessed the effects of (1) the current and planned road infrastructure, and (2) forest loss and gain, on the remaining large forest landscape massifs as green infrastructure at the EU's eastern border region in post -socialistic transition. First, habitat patch and network functionality in 1996-98 was assessed using habitat suitability index modelling. Second, we made expert interviews about road development with planners in 10 administrative regions in Poland, Belarus and Ukraine. Third, forest loss and gain inside the forest massifs, and gain outside them during the period 2001-14 were measured. This EU cross -border region hosts four remaining forest massifs as regional green infrastructure hotspots. While Poland's road network is developing fast in terms of new freeways, city bypasses and upgrades of road quality, in Belarus and Ukraine the focus is on maintenance of existing roads, and no new corridors. We conclude that economic support from the EU, and thus rapid development of roads in Poland, is likely to reduce the permeability for wildlife of the urban and agricultural matrix around existing forest massifs. However, the four identified forest massifs themselves, forming the forest landscape green infrastructure at the EU's east border, were little affected by road development plans. In contrast, forest loss inside massifs was high, especially in Ukraine. Only in Poland forest loss was balanced by gain. Forest gain outside forest massifs was low. To conclude, pro-ctive and collaborative spatial planning across different sectors and countries is needed to secure functional forest green infrastructure as base for biodiversity conservation and human well-being. (C) 2017 Published by Elsevier Ltd.
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| 5. |
- Angelstam, Per, et al.
(författare)
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Green infrastructure maintenance is more than land cover: large herbivores limit recruitment of key-stone tree species in Sweden
- 2017
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Ingår i: Landscape and Urban Planning. - : Elsevier BV. - 0169-2046 .- 1872-6062. ; 167, s. 368-377
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Tidskriftsartikel (refereegranskat)abstract
- Due to anthropogenic alteration of stand composition and landscape pattern in Swedish forest landscapes managed for industrial wood production, remnant patches of deciduous forests and woodlands do not form a functional green infrastructure for biodiversity conservation. We assessed if large herbivore browsing hampers the restoration of deciduous forest as green infrastructure by reducing the recruitment of boreal and temperate deciduous tree species of particular importance for biodiversity conservation. A natural experiment approach was applied in the distinct Swedish temperate-boreal forest gradient in Sweden. We measured the potential for saplings of aspen, rowan, sallow and oak to become recruited into the population of ecologically mature trees, as well as the amount of tree and field layer food. Sampling was made in forest stands representing four strata of managed forest landscapes accessible to large herbivores (experiment) and human settlements avoided by large herbivores (control). All four focal deciduous tree species had lower damage levels in controls (towns and villages) compared to experimental (forest) sites. While tree forage was much more abundant in controls, field layer forage in controls was not different from experimental stands. For all tree species except aspen we found a positive relationship between damage levels and large herbivore abundance, to which moose contributed > 89%. We discuss the role of research design for assessing the impact of large herbivores on plants, and highlight the need for integration of multi-species wildlife management as well as conservation planning and management.
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| 6. |
- Angelstam, Per, et al.
(författare)
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Measurement, Collaborative Learning and Research for Sustainable Use of Ecosystem Services: Landscape Concepts and Europe as Laboratory
- 2013
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Ingår i: AMBIO: A Journal of the Human Environment. - : Springer Science and Business Media LLC. - 0044-7447 .- 1654-7209. ; 42, s. 129-145
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Tidskriftsartikel (refereegranskat)abstract
- Policies at multiple levels pronounce the need to encompass both social and ecological systems in governance and management of natural capital in terms of resources and ecosystems. One approach to knowledge production and learning about landscapes as social-ecological systems is to compare multiple case studies consisting of large spaces and places. We first review the landscape concepts' biophysical, anthropogenic, and intangible dimensions. Second, we exemplify how the different landscape concepts can be used to derive measurable variables for different sustainability indicators. Third, we review gradients in the three dimensions of the term landscape on the European continent, and propose to use them for the stratification of multiple case studies of social-ecological systems. We stress the benefits of the landscape concepts to measure sustainability, and how this can improve collaborative learning about development toward sustainability in social-ecological systems. Finally, analyses of multiple landscapes improve the understanding of context for governance and management.
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| 7. |
- Angelstam, Per, et al.
(författare)
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Transitioning from Soviet wood mining to sustainable forest management by intensification: are tree growth rates different in northwest Russia and Sweden?
- 2017
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Ingår i: Forestry. - : Oxford University Press (OUP). - 0015-752X .- 1464-3626. ; 90, s. 292-303
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Tidskriftsartikel (refereegranskat)abstract
- Russian forest policy stipulates that intensified wood production is part of sustainable forest management. Swedish forest practices form a role model for this ambition. However, are the biophysical conditions for tree growth the same in northwest (NW) Russia and Sweden? We compared growth rates of young Scots pine (Pinus silvestris L.) and Norway spruce (Picea abies H. Karst.) at 58 degrees, 60 degrees, 62 degrees, 64 degrees N in both countries. Stands on rich, mesic and poor sites were sampled using the intercept method as an indicator of the actual tree growth rate. Young Scots pine growth did not differ between NW Russia and Sweden, and should thus, if managed in the same way, have the same rate of wood production. However, for Norway spruce growth rates were 20 per cent lower in Russia than in Sweden. This was linked to few young spruce trees growing without removing competing deciduous trees in Russia. All Swedish stands had been pre-commercial cleaned, but this treatment had only been applied to 5 per cent of the Russian stands. We discuss that intensification towards sustainable forest management requires knowledge not only about forest ecology, but also a toolbox for governance, planning and management. This requires learning about societal development trajectories linked to ownership, governance and tenure systems as well as forest landscape history.
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| 8. |
- Angelstam, Per, et al.
(författare)
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Wood production and biodiversity conservation are rival forestry objectives in Europe's Baltic Sea Region
- 2018
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Ingår i: Ecosphere. - : Wiley. - 2150-8925. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- The policy term green infrastructure highlights the need to maintain functional ecosystems as a foundation for sustainable societies. Because forests are the main natural ecosystems in Europe, it is crucial to understand the extent to which forest landscape management delivers functional green infrastructures. We used the steep west-east gradient in forest landscape history, land ownership, and political culture within northern Europe's Baltic Sea Region to assess regional profiles of benefits delivered by forest landscapes. The aim was to support policy-makers and planners with evidence-based knowledge about the current conditions for effective wood production and biodiversity conservation. We developed and modeled four regional-level indicators for sustained yield wood production and four for biodiversity conservation using public spatial data. The western case study regions in Sweden and Latvia had high forest management intensity with balanced forest losses and gains which was spatially correlated, thus indicating an even stand age class distribution at the local scale and therefore long-term sustained yields. In contrast, the eastern case study regions in Belarus and Russia showed spatial segregation of areas with forest losses and gains. Regarding biodiversity conservation indicators, the west-east gradient was reversed. In the Russian, Belarusian, and Latvian case study regions, tree species composition was more natural than in Sweden, and the size of contiguous areas without forest loss was larger. In all four case study regions, 54-85% of the total land base consisted of forest cover, which is above critical fragmentation thresholds for forest landscape fragmentation. The results show that green infrastructures for wood production and biodiversity conservation are inversely related among the four case study regions, and thus rival. While restoration for biodiversity conservation is needed in the west, intensified use of wood and biomass is possible in the east. However, a cautious approach should be applied because intensification of wood production threatens biodiversity. We discuss the barriers and bridges for spatial planning in countries with different types of land ownership and political cultures and stress the need for a landscape approach based on evidence-based collaborative learning processes that include both different academic disciplines and stakeholders that represent different sectors and levels of governance.
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| 9. |
- Elbakidze, Marine, et al.
(författare)
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A bottom-up approach to map land covers as potential green infrastructure hubs for human well-being in rural settings : A case study from Sweden
- 2017
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Ingår i: Landscape and Urban Planning. - : Elsevier BV. - 0169-2046 .- 1872-6062. ; 168, s. 72-83
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Tidskriftsartikel (refereegranskat)abstract
- Green infrastructure (GI) policy encourages the spatial planning of natural and semi-natural areas to deliver biodiversity conservation and a wide range of ecosystem services (ES) important to human well-being. Much of the current literature relies on expert-led and top-down processes to investigate connections between landscapes' different land covers and ES. Little is known regarding the preferences of residents, and how they connect land covers with the delivery of ES important for their well-being. The aim of this study is to identify and locate such land cover types as GI that provide multiple ES important for human well-being in rural settings. First, we interviewed 400 urban and rural residents to identify ES important for personal well-being and the land covers that deliver multiple ES in three counties that best represent the existing rural-urban gradient in Sweden. Second, to support the inclusion of GI in spatial planning, we identified and located spatial concentrations of individual land covers providing multiple ES (GI hubs) and significant clusters of such land covers (GI hotspots). The majority of urban and rural respondents associated their well-being with lakes, mountains above the tree line, old-growth forests, wooded-pastures, mature pine forests and rural farmsteads. The areal proportion of each type of hub was low, on average 3.5%. At least three land management strategies are needed to sustain GI hubs: maintenance of the composition, structure and function of natural ecosystems in protected areas; support for traditional agroforestry and villages as social-ecological systems; and diversification of the current intensive forest management approach.
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| 10. |
- Elbakidze, Marine, et al.
(författare)
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Hållbar landsbygdsutveckling : samverkan för kunskapsproduktion och lärande
- 2017
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Ingår i: Fakta. Skog. - 1400-7789.
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Annan publikation (populärvet., debatt m.m.)abstract
- Landsbygdens naturresurser och andra värden är viktiga för att vidareutveckla en biobaserad ekonomi och att stärka Sverige som besöksnation. Därför är det viktigt med befolkade, aktiva och växande landsbygder. Landsbygden står dock inför stora utmaningar. Hur skapas attraktiva bygder? Hur bevaras gamla jobb, och skapas nya? Hur bevaras ekologiska, sociala och kulturella värden? Genom tvärvetenskaplig forskning tillsammans med aktörer på olika samhällsnivåer verkar vi för en hållbar landsbygd genom att generera kunskap och bidra till lärande. Vårt internationella arbetssätt ger nya perspektiv på kunskapsproduktion och lärande tillsammans med praktiker, och skapar förutsättningar för problembaserad utbildning för hållbar landsbygdsutveckling. Här presenteras huvudinriktningarna för vår forskning för hållbar landsbygdsutveckling.
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