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• Investigation on three commercial products used to clean varnished wooden furniture. • Non-destructive method for the study of interactions of wood with cleaning products. • Relevant for conservation treatments of wooden furniture in historical collections. The Royal Palace of Norway has a large 19th century wooden furniture collection and most of it is coated with shellac-based varnishes. Since these objects are part of the royal collections, they are still in daily use at the different residences and, therefore, need to be frequently cleaned. In this work, the effect of three cleaning commercial products (Baolin, Centurio, Fulgentin) used at the royal collections on shellac-coated mahogany is investigated for the first time. A non-invasive methodology (portable ER-FTIR spectroscopy and colorimetry) was applied to assess whether the chemical composition and the color of fresh and artificially aged mahogany wood mock-ups coated with shellac were affected by the above-mentioned cleaning products. This study shows that one of them causes changes in the varnished wood, thus potentially affecting the long-term conservation of this furniture collection. [ABSTRACT FROM AUTHOR]

Forest management is an important tool for GHG mitigation by representing three carbon pools: living biomass, forest soil, and wood-based products. Additionally, increasing attention has been given to the potential for wood products to substitute fossil-intensive products as a climate mitigation strategy. The goal of this paper is to analyse the theoretical GHG effects of fully replacing four common non-wood products with wood-based products of 'low' and 'high' technology options that have a similar functionality: (1) Spruce particle board substituting polyurethane (PU) foam insulation board; (2) spruce cross-laminated timber beam (CLT) substituting steel beam; (3) birch energy wood substituting electric heating; and (4) birch plywood substituting plaster board. The analysis was based on forestry in Western Norway as a case study, where forests typically consist of naturally generated birch and expanding areas of planted Norway spruce. In this study we compare wood products derived from paired stands of Norway spruce and downy birch. The analysis showed that spruce gave a higher theoretical substitution effect relative to birch for the selected pairs of woody and non-woody products. CLT substituting steel beam gave the highest substitution effect, approximately 15% higher than particle board substituting PU foam board. The theoretical substitution effect in mass units of carbon per kg wood product for the two spruce wood products was approximately 17 times higher relative to substituting Norwegian hydro energy-based electric heating, whereas plywood substituting plaster board may in fact increase GHG emissions. As the gross emissions were relatively similar for the birch plywood and the spruce particle board, the major substitution effect was related to the avoided emission of the non-woody product rather than to the tree species per se. The paper concludes that the choice of product to be substituted was the key factor that determined the final substitution effects. Furthermore, the study showed that transportation was the single most important factor that affected the emissions between planting and delivery of the timber at production gate. The analysis enables informed decisions related to CO 2 -emissions at the various steps from tree planting to wood conversion, and underline the importance of informed decision related to the choice of substitution products. • We compared the theoretical substitution effect of four wood products (spruce particle board, spruce cross-laminated timber beam, birch energy wood, and birch plywood) for the case of Western Norway. • The spruce products gave a better substitution effect relative to birch, and cross laminated beam from spruce substituting steel beam had the highest substitution effect amongst the four selected alternatives. • Avoided emission was the major determining factor for the calculated substitution effect, thus, the estimated substitution factors were mainly related to the selected product to be substituted rather than to the tree species used as raw material. • Emissions related to transportation was the single most important emission factor of all forestry activities, amounting to approximately 48% of the estimated emissions. Export by boat suggested a potential increase in the transport emissions of 62%. [ABSTRACT FROM AUTHOR]

• Phenology of wood shows high variability across locations, species and years. • The coupling between leaf- and wood growth phenology has few generic trends. • Temperature and climate are key drivers of wood growth phenology variability. • Summer droughts shortens the wood-growing season. Wood growth phenology of temperate deciduous trees is less studied than leaf phenology, hindering the understanding of their interaction. In order to describe the variability of wood growth and leaf phenology across locations, species and years, we performed phenological observations of both xylem formation and leaf development in three typical temperate forest areas in Western Europe (Northern Spain, Belgium and Southern Norway) for four common deciduous tree species (Fagus sylvatica L., Betula pendula Roth., Populus tremula L. and Quercus robur L.) in 2018, 2019 and 2020, with only beech and birch being studied in the final year. The earliest cambial reactivation in spring occurred at the Belgian stands while the end of cambial activity and wood growth cessation generally occurred first in Norway. Results did not show much consistency across species, sites or years and lacked general patterns, except for the end of cambial activity, which occurred generally first in birch. For all species, the site variation in phenophases (up to three months) was substantially larger than the inter-annual variability (up to six weeks). The timeline of bud-burst and cambium reactivation, as well as of foliar senescence and cessation of wood growth, were variable across species even with the same type of wood porosity. Our results suggest that wood growth and leaf phenology are less well connected than previously thought. Linear models showed that temperature is the dominant driver of wood growth phenology, but with climate zone also having an effect, especially at the start of the growing season. Drought conditions, on the other hand, have a larger effect on the timing of wood growth cessation. Our comprehensive analysis represents the first large regional assessment of wood growth phenology in common European deciduous tree species, providing not only new fundamental insights but also a unique dataset for future modelling applications. [ABSTRACT FROM AUTHOR]

The development of non-biocidal and environmentally friendly systems to protect wood against biological decay has become a high priority in recent years. In the present study the impact of an innovative modification procedure, combining two environmentally friendly modification methods: thermal modification and mineralisation, using an aqueous solution of calcium acetoacetate as a precursor, on the fungal durability of wood was evaluated. European beechwood (Fagus sylvatica) and Norway sprucewood (Picea abies) were selected as model wood species. Wood samples were treated using either a single or combination of both methods and exposed to four different fungi: Gloeophyllum trabeum , Rhodonia placenta , Trametes versicolor and Pleurotus ostreatus. The effect of the different modifications on moisture content, dynamic vapour sorption, contact angle and pH value was also evaluated. Overall, the highest durability against Rhodonia placenta , Trametes versicolor and Pleurotus ostreatus was achieved through thermal modification in both wood species, while the combination of mineralisation and thermal modification has a synergistic effect against degradation by Gloeophyllum trabeum. In the case of beechwood the mass loss decreased from 41% for native to 6% for combined modified samples. We proved that the effectiveness of different treatment against fungal decay of wood were in strong dependence of their moisture content, dynamic vapour sorption, contact angle and pH values. The role of fungi on the morphology of the wood and on crystal structure of formed carbonate was investigated using SEM-EDS analysis. [Display omitted] • Presented ecological modification of wood can be an alternative to biocides. • A significant improvement in the fungal durability of wood was achieved. • Thermal modification and mineralisation work synergistic against wood decay fungi. • The reasons for a synergistic effect of combining methods were proposed. • The mass loss decreased from 41% for native to 6% for combined modified beechwood. [ABSTRACT FROM AUTHOR]

• Drought advances cessation of wood growth in Betula pendula. • Drought can delay autumn leaf phenology. • A potential drought lag-effect was found on autumn leaf phenology in the next year. • Wood growth is more sensitive to site fertility than autumn leaf phenology. Historically, the autumn dynamics of deciduous forest trees have not been investigated in detail. However, autumn phenological events, like onset of loss of canopy greenness (OLCG), onset of foliar senescence (OFS) and cessation of wood growth (CWG), have an important impact on tree radial growth and the entire ecosystem's seasonal dynamics. Here, we monitored the leaf and wood phenological events of silver birch (Betula pendula) at four different sites in Ås, southeastern Norway: (a) a natural mature stand, (b) a plantation on former agricultural ground, (c) young natural trees, and (d) young trees in pots under different fertilization levels. The study took place over four consecutive years (from 2017 to 2020), with a particular focus on 2018, a year in which there was a severe summer drought, and the next year, 2019, which featured more normal conditions. First, we provided a description of birch phenology within its mid-north distributional. Second, we showed that drought advanced CWG by about 5 to 6 weeks and it delayed OLCG and OFS up to 30 days. Third, we observed an unexpected advance in OLCG in 2019 compared to 2018 (30 days) and 2020 (14 days). OFS presented similar dynamics as OLCG, whereas CWG was advanced only in 2018. These findings might indicate lag-effects of severe drought on the next year autumn leaf phenology but not on wood growth. On the other hand, the comparison between the natural stand and the plantation showed that, under drought conditions, wood growth is more sensitive to site fertility than autumn leaf phenology. In summary, our study elucidated the autumn dynamics of an important deciduous forest species in the northern temperate zone and showed unexpected impacts of a severely dry and warm summer on the current and next year leaf phenology. [ABSTRACT FROM AUTHOR]

Abstract: Production of the oxidoreductive lignin-modifying enzymes – lignin and manganese peroxidases (MnPs), and laccase – of the white-rot basidiomycete Phlebia radiata was investigated in semi-solid cultures supplemented with milled grey alder or Norway spruce and charcoal. Concentrations of nutrient nitrogen and Cu-supplement varied also in the cultures. According to extracellular activities, production of both lignin peroxidase (LiP) and MnP was significantly promoted with wood as carbon source, with milled alder (MA) and low nitrogen (LN) resulting with the maximal LiP activities (550 nkat l−1) and noticeable levels of MnP (3 μkat l−1). Activities of LiP and MnP were also elevated on high nitrogen (HN) complex medium when supplemented with spruce and charcoal. Maximal laccase activities (22 and 29 μkat l−1) were obtained in extra high nitrogen (eHN) containing defined and complex media supplemented with 1.5 mM Cu2+. However, the nitrogen source, either peptone or ammonium nitrate and asparagine, caused no stimulation on laccase production without Cu-supplement. This is also the first report to demonstrate a new, on high Cu2+ amended medium produced extracellular laccase of P. radiata with pI value of 4.9, thereby complementing our previous findings on gene expression, and cloning of a second laccase of this fungus. [Copyright &y& Elsevier]

Food availability in fjords is unusual among deep-sea environments due to the increased availability of nutritional sources that are comparatively rare in the open sea, such as influxes of macrophytodetritus and terrestrial organic matter. In open waters, these deep-sea 'organic falls' have been shown to increase beta diversity in comparison to surrounding, unenriched sediments, and support a range of specialised fauna. There has been unprecedented loss of coastal kelp forests in Norway and this is likely to greatly reduce the transfer of an important carbon subsidy to deep-sea communities in Norwegian fjords. In contrast, progress in terrestrial land management and reforestation has resulted in a large increase in the area covered by boreal forests. With such an expansion in forests fringing deep Norwegian fjords, an increase in the transport of wood material and forest detritus to these deep-sea habitats seems inevitable. Benthic landers containing experimental substrates (wood blocks and kelp parcels) were deployed for 10 months at a depth of 530 m in Osterfjorden, and stable isotope analysis (13C, 15N) was used to investigate and compare trophic relationships between wood and kelp substrates and the macrofauna that colonised them. Trophic shift analyses showed a dependence on kelp either as a direct dietary source or a primary source of carbon in most of the fauna analysed, whereas there was little evidence of wood providing an importance dietary subsidy. Modelling analyses showed that kelp detritus comprised a large percentage of the diet of all of the taxa collected from the kelp samples, and several from the wood samples. Ontogenetic trophic changes (i.e., differences in δ13C or δ15N depending on animal size) were seen in several of the taxa analysed, revealing changes in dietary preference and increasing trophic level as a function of size/age. This study provides evidence of the importance of kelp in the trophic ecology of communities living at the Norwegian deep-sea floor. The continued loss of kelp from shallow, coastal systems may have profound effects for these communities as they face a reduction in this important subsidy. • In situ experiment using benthic landers at ~530 m depth. • Landers deployed for 10 months in Osterfjorden, Norway. • Experimental substrates: wood and kelp. • Stable isotope modelling in MixSIAR showed a large portion of the diet of deep fjord fauna consisted of kelp detritus. • Ontogenetic trophic changes seen in several of the taxa analysed. [ABSTRACT FROM AUTHOR]

The purpose of the present work was to investigate whether the drying method itself affects strength of wood apart from fibre direction, density, temperature in the wood, moisture content and with which angle the microfibril is placed in the middle layer at the secondary cell wall S2. The drying methods compared were microwave drying and conventional air-circulation drying, and the species tested was Norway spruce. The result shows that it is not possible to demonstrate any difference between the two drying methods with respect to the strength of the wood. What affects wood strength are such variables as moisture content, number of annual rings and the density properties weight, width and thickness. [Copyright &y& Elsevier]

• A Scots pine log was placed in the outdoor environment before naturally being dried. • The fracture tests were conducted on DCB specimens with TR crack orientation system. • Fracture toughness trend vs. the longitudinal moisture content gradient was studied. • Fracture toughness hinged upon the crack orientation and moisture content value. The mode I critical stress intensity factor of a Scots pine beam was studied in the tangential-radial crack propagation system. The beam was naturally dried in the lab enviroment following a year and a half-long exposure to the harsh climate of Trondheim in Norway. A comparison between critical stress intensity factor values obtained by means of experimental and theoretical approaches were made. Finite Element analysis along with the critical stress intensity factor tests were carried out to identify the values in the former datasets, while to create the latter datasets, a modified relation, on the basis of The ASTM 399–20 Standard, was propsed. The values in the above mentioned datasets, were in close correspondence together. Furthermore, the moisture content within the radial and longitudinal directions of the beam using the relative humidity and response time of the samples was studied. Finally, the relation between the moisture content and the critical stress intensity factor along the length of the beam was investigated and compared with the reported data in the literature. It was found that the pre-experimental conditioning of the wood and crack directionality system had a considerable impact on the values of critical stress intensity factor. [ABSTRACT FROM AUTHOR]