| 1. |
- Blennow, Kristina, et al.
(författare)
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Implementing storm damage in a dynamic vegetation model for regional applications in Sweden
- 2012
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Ingår i: Ecological Modelling. - : Elsevier BV. - 0304-3800 .- 1872-7026. ; 247, s. 71-82
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Tidskriftsartikel (refereegranskat)abstract
- Wind is the dominant agent of damage in forests in Western Europe. Traditional wind-damage models calculate a probability for damage or a critical wind speed at which damage occurs. However, in a dynamic vegetation model actual damage to stands and individual trees is needed to get a dynamical progression of the vegetation. We present a prototype for a new approach to modelling forest wind damage at the regional scale, which we incorporate within a dynamic vegetation model. The approach is based on knowledge from both empirical and mechanical models and calculates the damaged fraction of a cohort based on wind load and a sensitivity that depends on the current physical state and history of the cohort in relation to the ecosystem. The modelling concept has been developed, calibrated and evaluated for Swedish conditions but can be applicable to other similar areas with minor modification. Because of the stochastic nature of local wind load and the difficulty of describing the stand-level exposure, the ability to explain observed damage at stand level was low. Regional level variation in damage, which more depends on the wind load, was however explained reasonably well (R-2 = 0.43). We suggest that this is a useful concept for evaluating alternatives of forest management under different climate scenarios in the process of adaptation to future storm-damage risks. (C) 2012 Elsevier B.V. All rights reserved.
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| 2. |
- Stridbeck, Petter, et al.
(författare)
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Partly decoupled tree-ring width and leaf phenology response to 20th century temperature change in Sweden
- 2022
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Ingår i: Dendrochronologia. - : Elsevier BV. - 1125-7865 .- 1612-0051. ; 75
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Tidskriftsartikel (refereegranskat)abstract
- The recent warming trend, and associated shifts in growing season length, challenge the principle of uniformitarianism, i.e., that current relations are persistent over time, and complicates the uncritical inferences of past climate from tree-ring data. Here we conduct a comparison between tree-ring width chronologies of Pinus sylvestris L. (Scots pine), Picea abies (L.) Karst. (Norway spruce) and Betula pubescens Ehrh. (Downy birch) and phenological observations (budburst and leaf senescence) of Fagus sylvatica L. (European beech), Quercus robur L. (European oak), Betula sp. (Birch), Norway spruce and Scots pine) in Sweden to assess to what extent the tree-ring width–temperature relationship and the timing of phenological phases are affected by increased temperature. Daily meteorological observations confirm a prolongation of the thermal growing season, most consistently observed as an earlier onset of around 1–2 weeks since the beginning of the 20th century. Observations of budburst closely mimic this pattern, with budburst of the deciduous trees occurring 1–2.5 weeks earlier. In contrast to the changes seen in phenology and observational temperature data, the tree-ring width–temperature relationships remain surprisingly stable throughout the 20th century. Norway spruce, Scots pine and Downy birch all show consistently significant correlations with at least one 30 day-long window of temperature starting in late June–early July season. Norway spruce displays the largest degree of stability, with a consistent 60 day-long temperature window with significant correlation starting around Julian calendar day 150. Thus, our results suggest that the principle of uniformitarianism is not violated during the period covered by modern meteorological observations. Further research is needed to determine at what thresholds the temperature sensitivity of these species may alter or deteriorate as a consequence of the ongoing climate change.
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| 3. |
- Jönsson, Anna Maria, et al.
(författare)
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Annual changes in MODIS vegetation indices of Swedish coniferous forests in relation to snow dynamics and tree phenology
- 2010
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Ingår i: Remote Sensing of Environment. - : Elsevier BV. - 0034-4257 .- 1879-0704. ; 114:11, s. 2719-2730
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Tidskriftsartikel (refereegranskat)abstract
- Remote sensing provides spatially and temporally continuous measures of forest reflectance, and vegetation indices calculated from satellite data can be useful for monitoring climate change impacts on forest tree phenology. Monitoring of evergreen coniferous forest is more difficult than monitoring of deciduous forest, as the new buds only account for a small proportion of the green biomass, and the shoot elongation process is relatively slow. In this study, we have analyzed data from 186 coniferous monitoring sites in Sweden covering boreal, southern-boreal, and boreo-nemoral conditions. Our objective was to examine the possibility to track seasonal changes in coniferous forests by time-series of MODIS eight-day vegetation indices, testing the coherence between satellite monitored vegetation indices (VI) and temperature dependent phenology. The relationships between two vegetation indices (NDVI and WDRVI) and four phenological indicators (length of snow season, modeled onset of vegetation period, tree cold hardiness level and timing of budburst) were analyzed. The annual curves produced by two curve fitting methods for smoothening of seasonal changes in NDVI and WDRVI were to a large extent characterized by the occurrence of snow, producing stable seasonal oscillations in the northern part and irregular curves with less pronounced annual amplitude in the southern part of the country. Measures based on threshold values of the VI-curves, commonly used for determining the timing of different phenological phases, were not applicable for Swedish coniferous forests. Evergreen vegetation does not have a sharp increase in greenness during spring, and the melting of snow can influence the vegetation indices at the timing of bud burst in boreal forests. However, the interannual variation in VI-values for specific eight-day periods was correlated with the phenological indicators. This relation can be used for satellite monitoring of potential climate change impacts on northern coniferous spring phenology. (C) 2010 Elsevier Inc. All rights reserved.
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| 4. |
- Jönsson, Anna Maria, et al.
(författare)
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Enhanced science-stakeholder communication to improve ecosystem model performances for climate change impact assessments.
- 2015
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Ingår i: Ambio: a Journal of Human Environment. - : Springer Science and Business Media LLC. - 0044-7447. ; 44:3, s. 249-255
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Tidskriftsartikel (refereegranskat)abstract
- In recent years, climate impact assessments of relevance to the agricultural and forestry sectors have received considerable attention. Current ecosystem models commonly capture the effect of a warmer climate on biomass production, but they rarely sufficiently capture potential losses caused by pests, pathogens and extreme weather events. In addition, alternative management regimes may not be integrated in the models. A way to improve the quality of climate impact assessments is to increase the science-stakeholder collaboration, and in a two-way dialog link empirical experience and impact modelling with policy and strategies for sustainable management. In this paper we give a brief overview of different ecosystem modelling methods, discuss how to include ecological and management aspects, and highlight the importance of science-stakeholder communication. By this, we hope to stimulate a discussion among the science-stakeholder communities on how to quantify the potential for climate change adaptation by improving the realism in the models.
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| 5. |
- Olofsson, Jörgen, et al.
(författare)
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Educating the next generation decision makers - the multi-disciplinary classroom as a platform for developing communication skills needed for future progress of adaptation measures
- 2015
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Konferensbidrag (refereegranskat)abstract
- The scientific knowledge of climate change processes and their worrying future implications for human societies and natural systems has developed considerably during the last decade, but necessary adaptive actions by decision makers have so far been rather limited. There are several causes to this, such as a discrepancy related to the communication between climate scientists and end-users, and the lack of climate educational background of several decision makers. This results in decision makers not fully incorporating knowledge on climate change and impacts into adaptive action measures. Hence, educating future decision makers, as well as scientists providing the climate knowledge, is therefore highly important in order to minimise this reduction of knowledge transfer, and by so improve the necessary decision processes of climate actions. Here we report how the Department of Physical Geography and Ecosystem Sciences, and the Centre for Environmental and Climate Research at Lund University, work on continuously improving climate communication skills of our Masters students. Throughout the academic programs with Masters in Physical Geography and Ecosystem Analysis, and in Climate Strategy, our students have mixed educational background (ranging from meteorologists to geographers, from biologists to engineers as well as political science students) which generates a unique classroom environment for learning communication across borders of different understanding and knowledge background. Here we present interesting outcomes of such a set-up, including work hands-on with issues related to climate change, impacts and adaptation through exercises, seminars and projects. Students learn how to systematically treat background climate information and carefully analyse their results, and to efficiently communicate their findings through written reports and oral presentations. Teachers provide formative constructive feedback on assignments throughout the programs, for students to improve their subject knowledge and understanding as well as their communication performance. To further motivate our students, external professionals from enterprises and authorities working on climate related issues are frequently invited as guest lecturers, which also may act as co-supervisors of degree projects. These networks also contribute to valuable transfer of scientific knowledge between our departments and the non-academia world. Furthermore, teachers are encouraged to develop their own communication skills by e.g. attend tailored pedagogic courses and conferences. Our Master programs provide a highly stimulating learning environment in which students are trained to become effective communicators of climate related knowledge, being able to critically analyse climate information, impact probabilities, and adaptation strategies, and thereby to take on the role as decision makers.
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| 6. |
- Akselsson, Cecilia, et al.
(författare)
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Synergier och konflikter mellan miljömål i skogen
- 2021
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Ingår i: Dragkampen om skogen : en syntes om skogsbruk i perspektivet av klimat, miljö och biologisk mångfald - en syntes om skogsbruk i perspektivet av klimat, miljö och biologisk mångfald. - 9789198434972 ; :7, s. 30-55
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Bokkapitel (populärvet., debatt m.m.)
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| 7. |
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| 8. |
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| 9. |
- Jaakkola, Erica, et al.
(författare)
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Spruce bark beetles (Ips typographus) cause up to 700 times higher bark BVOC emission rates compared to healthy Norway spruce (Picea abies)
- 2023
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Ingår i: Biogeosciences. - : Copernicus GmbH. - 1726-4189. ; 20:4, s. 803-826
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Tidskriftsartikel (refereegranskat)abstract
- Biogenic volatile organic compound (BVOC) emissions from trees subjected to biotic stress are higher compared to healthy trees, and they may also have a different compound composition. This in turn affects atmospheric chemistry and can lead to either positive or negative feedback to the climate. Climate change favors the abundance of the European spruce bark beetle (Ips typographus) which attacks the bark of Norway spruce (Picea abies) trees, causing induced BVOC emissions from the trees as a response to the insect stress. Here, results are reported from a study analyzing the difference in emission rates between healthy and bark-beetle-infested Norway spruce trees, changes in emission rates over time since the infestation started, and differences in emission rates from bark-beetle-drilled entry and exit holes.Bark chamber measurements on both healthy and infested trees were performed during the summer of 2019 at Hyltemossa and Norunda research stations in Sweden. The measurements showed that induced BVOC emissions following the bark beetle infestation were dominated by entry hole emissions in the early growing season and exit hole emissions in the later season. The results showed a significant difference in emission rates between healthy and infested trees during both seasons. The seasonal average standardized BVOC emission rate of healthy trees was 32 ± 52 µg m−2 h−1 (mean ± standard deviation), while the average standardized BVOC emission rates of infested trees were 6700 ± 6900 and 2000 ± 1300 µg m−2 h−1 during the early and late season respectively. BVOC emission rates were highest at the start of the infestation and decreased exponentially with time, showing induced emission rates for up to 1 year after which the emission rates were similar to those from healthy bark. Constitutive needle emission rates from healthy trees were found to be 11 times higher than bark emissions from healthy trees. However, when Norway spruce trees were infested, the bark emission rates were instead 6 to 20 times higher than the needle emissions, causing substantial increases in the total tree BVOC emission rate. This could lead to high impacts on atmospheric processes, specifically the formation of secondary organic aerosols, which have a higher yield from some monoterpene compounds, which increased from infested trees.
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| 10. |
- Jönsson, Anna Maria, et al.
(författare)
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Reflections on Science–Stakeholder Interactions in Climate Change Adaptation Research within Swedish Forestry
- 2014
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Ingår i: Society & Natural Resources. - : Informa UK Limited. - 0894-1920 .- 1521-0723. ; 27:11, s. 1130-1144
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Tidskriftsartikel (refereegranskat)abstract
- Stakeholder engagement has become increasingly important in research programs focusing on climate change impact on ecosystem services. Communication between researchers and stakeholders, however, is often impaired by linguistic barriers, different priorities, and time constraints. This article examines the organizational aspects of science–stakeholder interactions, focusing on examples from the Swedish forestry sector. The study highlights the need articulated by the Swedish forestry sector for access to scientific knowledge, and we discuss how to present research findings in formats suitable to serve as decision support. Clear communication about common goals, expectations, resources, and time frames is needed in order to reduce the risk of stakeholder fatigue.
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