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• risk analysis of climate-induced fatigue on wooden surfaces inside six rural Swedish churches. • Past monitoring campaigns used for gathering info about number/entity of thermal fluctuations. • Investigated constant- and variable-amplitude climate-induced fatigue behaviors. ○ Assessed possible damage accumulation caused by repeated thermal fluctuations over time. ○ Compared results with surface decay level from in-situ conservation surveys. Environmental variations of Temperature (T) and Relative Humidity (RH) in air cause a superficial and/or sub-surface deformation (shrinkage/swelling) of organic hygroscopic objects, as for example wood. These environmental variations may be due to the natural variability of climate, to the use of Heating, Ventilation and Air Conditioning (HVAC) systems and to the presence of people. This contribution focuses on a group of wooden rural churches located in harsh climates in Sweden. The churches, which are still in use for the local communities, are heated during wintertime to reach acceptable indoor comfort levels causing potentially risky T and RH fluctuations for hygroscopic objects. In this framework, the main goal is assessing the risk of fracture on wooden structural elements caused by hygrothermal fluctuations. The method is based on a preliminary approach for reconstructing the climate history experienced by a typical wooden structural element of these churches and that, over time, results in a cyclic fatigue loading, naturally induced by the outdoor climate. Then, the effect of the artificial heating on the indoor microclimate and, therefore, on the reconstructed fatigue curve is assessed. Main outcomes were obtained by using a methodology that is preliminary based on simplifying assumptions, due to a severe lack of knowledge, in literature, about the fatigue behavior of wood. Finally, main considerations on the fatigue behavior of exposed wooden elements are drawn up, namely the estimation of their residual life (or "life-to-damage"), which may support conservators or church managers in better managing the microclimate to reduce the risk of fracture on valuable objects. [ABSTRACT FROM AUTHOR]

The transition to a fossil-free society in Sweden is expected to cause an increased demand for forest-derived products which may intensify existing conflicts between forest ecosystem services. This study investigated the preferences among non-industrial private forest owners for maintaining multiple forest ecosystem services and their preferences for future forest development. The findings were related to their prioritizations for and knowledge of forest management. The study results were generated through the means of a survey which revealed a consistent high valuation among all respondents of ecosystem services relating to water quality, timber quality, recreation, and biodiversity. A majority of the respondents desired increasing proportions of mixed species and broadleaved stands within the future forest landscape. Certified forest owners who were members of a forest owner association (CMs) prioritized achieving high economic income through roundwood production with strong preferences for the ecosystem services high stand growth and high timber quality. For CMs, carbon substitution was the preferred means of mitigating climate change. Forest owners lacking both certification and membership in a forest owner association ranked the ecosystem services recreation and biodiversity significantly higher, and also preferred retaining more old forest within the landscape. The survey results revealed a higher management activity among CMs, resulting in a more frequent establishment of mixed and broadleaved stands. Forest owners with medium to large scale properties were well-represented within the CM category. The results indicated that while the CMs have stronger preferences for roundwood production compared to owners of small properties, they are also more likely to have taken adaptive measures favoring risk management and biodiversity. [ABSTRACT FROM AUTHOR]

This paper examines how agents inscribed their persona in buildings during the Renaissance in Scania in present-day Sweden. Through an analysis of stone tablets and timber beams with inscriptions, images, and dates, questions of identity and individuality are highlighted. The objects were often placed above doors in noble country residences or in buildings belonging to the urban elite. The paper discusses who was able to see and understand the messages communicated by the buildings, and when, how, and why the tradition of putting up this type of object on buildings emerged in a Scandinavian context. [ABSTRACT FROM AUTHOR]

This study assesses glulam and reinforced concrete (RC) beams in a multi-storey building in Gävle in Sweden. StruSoft FEM-Design software is used to conduct the current study. First, the building having the RC beams is modelled, analysed, and designed. Utilisation ratio, stress, weight, reaction force, stability, and deflection of the building are examined. It is concluded that the building can function well with RC beams. Then, the RC beams are replaced with glulam beams and the building is again analysed. It is revealed that larger cross-sections are needed for the replaced glulam beams in most of the spans compared with the RC beams in order for them to have acceptable results from the utilisation ratio viewpoint. However, for large spans of 8 m, a timber column is used in the mid-span for all the storeys as a strengthening alternative so that a shorter span for these glulam beams can be adopted which leads to acceptable results. Stresses of the RC and glulam beams are also evaluated. The building having the glulam beams is 23.79 % lighter than the building having the RC beams. The maximum reaction force of the building having the glulam beams is obtained 24.27 % lower than the building having the RC beams. Stability and deflection of the building in both cases are discussed as well. [ABSTRACT FROM AUTHOR]

The European spruce bark beetle (SBB) is an important insect pest in many countries such as Sweden and has caused the loss of millions of trees over the past few decades. Forest management targeting key variables in the forest can be a potential tool to decrease SBB susceptibility. In this paper, we simulated forest development over a 70-year planning horizon and evaluated the effect of different forest management strategies on spruce bark beetle susceptibility, timber production and biodiversity indicators. We used national forest inventory plots located in Kronoberg county, Southern Sweden, from 2016 to 2020 to perform the analyses. A reference strategy mimicking current management practices was simulated and compared with four other management strategies that can be an alternative to decrease spruce bark beetle damage. The four management strategies were (1) mixed forest stands, (2) shorter rotations and no thinnings, (3) prolonged rotations and (4) continuous cover forestry. The strategies differed in how and when regeneration, pre-commercial thinning, thinnings and final fellings were performed. The optimization of each of the strategies was aimed at reducing spruce bark beetle susceptibility while simultaneously investigating trade-offs with a range of timber production demands. In addition, we simulated a combined strategy where any of the strategies could be chosen with the objective of reducing spruce bark beetle susceptibility. Also, we evaluated each strategy with respect to biodiversity indicators described in the Swedish environmental quality objective Living Forests. The results show that a combination of all strategies is the most effective option to manage the forest to achieve the lowest average susceptibility in the analysed forest area. Shorter rotation management also resulted in low susceptibility. In addition, management strategies leading to large reductions in the abundance of large stem diameter Norway spruce trees in the landscape achieve lower susceptibility values. Our results suggest that various management strategies, alone or in combination with others, can be successfully employed to decrease forest susceptibility to spruce bark beetle damage. However, achieving multiple management objectives simultaneously, such as timber production and promotion of biodiversity, may require additional constraints in the mathematical models in addition to the settings used to describe each of the strategies. Future work should explore incorporating these additional constraints to better optimize management decisions. • We evaluate management impacts on forest susceptibility to Ips typographus. • Diversifying management is the best option to reduce Ips typographus susceptibility. • Reducing the abundance of large Norway spruce trees in the forest is key. • Our results suggest that management diversity mitigates disturbance risks. [ABSTRACT FROM AUTHOR]

• P. gigantea as biological control against root rot is not working in practice. • Failure in stump treatment of Norway spruce leads to Heterobasidion infections. • Swedish forest operators are not achieving sufficient coverage on the stumps. • In over a quarter of all stumps PCR failed to detect P. gigantea. • Future studies need to address failures in handling and application of P. gigantea. For about 25 years, forest managers in Sweden have been treating stumps following harvesting with Phlebiopsis gigantea , retailed as Rotstop®S gel, against spore infections of Heterobasidion , which cause root rot in order to minimize losses in timber production. However, not all forest managers trust the efficacy of stump treatment and this fact has hindered widespread adoption of stump treatment using P. gigantea. In this study, we evaluated stump treatment in the field during commercial thinning operations across 15 sites, by assessing the degree of stump coverage and subsequent infection levels in stump discs. In total, 45 % of all stumps were infected with Heterobasidion spp.. Nineteen percent of all stumps were considered to have full (100 %) coverage by Rotstop®S but contractors failed to achieve the manufacturers stipulated minimum coverage (85 %) in approximately 1/3 of all stumps. Using PCR, we could only detect the presence of P. gigantea in 73 % of the tested stumps. Large variation occurred between stump coverage and the recovery of P. gigantea in wood chip samples collected from stump discs across sites. In the worst case, we detected P. gigantea in only three out of ten treated stumps at one site. Despite this discrepancy we saw a clear reduction of the size of Heterobasidion infections on stumps where stump treatment coverage was more than 85 % of the stump surface. Our results suggest that forest operators in Sweden repeatedly fail to either apply a spore solution of P. gigantea or cover enough of the stumps to provide the desired protection. The outcome of such sub-standard application, could further undermine the usage of biological control agents in forestry and limit any potential control against Heterobasidion spp.. [ABSTRACT FROM AUTHOR]