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  • 1.
    Berg, Björn
    et al.
    Dipartimento biologia strutturale e funzionale, Complesso universitario di Monte S. Angelo, Napoli, Italy; Department of forest ecology, University of Helsinki, Helsinki, Finland.
    Davey, M. P.
    Department of plant sciences, University of Cambridge, Cambridge, United Kingdom.
    De Marco, A.
    Dipartimento biologia strutturale e funzionale, Complesso universitario di Monte S. Angelo, Napoli, Italy.
    Emmett, B
    Centre for ecology and hydrology, Bangor.
    Faituri, M.
    Department of soils and water, Omar AlMukhtar university, Elbeida, Libyan Arab Jamahiriya.
    Hobbie, S. E.
    Department of ecology, evolution and behavior, University of Minnesota, St. Paul, USA.
    Johansson, Maj-Britt
    University of Gävle.
    Liu, C.
    Department of landscape science and engineering, College of agriculture and biology, Shanghai, ChinaShanghai Jiao Tong university,.
    McClaugherty, C.
    Department of biology, Mount Union college, Alliance, USA.
    Norell, L.
    Unit of applied statistics and mathematics, SLU, Uppsala, Sweden.
    Rutigliano, F. A.
    Dipartimento di scienze ambientali, Seconda Università degli studi di Napoli, Caserta, Italy.
    Vesterdal, L.
    Forest & landscape Denmark, University of Copenhagen, Hørsholm, Denmark.
    Virzo De Santo, A.
    Dipartimento biologia strutturale e funzionale, Complesso universitario de Monte S. Angelo, Napoli, Italy.
    Factors influencing limit values for pine needle litter decomposition: A synthesis for boreal and temperate pine forest systems2010In: Biogeochemistry, ISSN 0168-2563, E-ISSN 1573-515X, Vol. 100, no 1, p. 57-73Article in journal (Refereed)
    Abstract [en]

    We synthesized available data for decomposition of pine (Pinus) needle litter in pine forests to determine the litter chemical characteristics and climate factors that explained variation in the limit value, i. e. the level of accumulated mass loss at which the decomposition process either continues at a very low rate or possibly stops. Our data base included 56 separate studies on decomposition of pine needle litter, spanning Scots pine, lodgepole pine, Aleppo pine, stone pine and white pine, mainly incubated at the site of collection. Studies had 5 to 19 samplings, on average 10, and the decomposition was followed to a mass loss ranging from 47 to 83%, on average 67%. The periods from 3.0 to 5.4 years, on average 3.9 years, were of sufficient duration to allow estimates of limit values of decomposition. We used a linear mixed model with regression effects to relate limit values to potential explanatory variables, namely the sites' long-term mean annual temperature (MAT) and mean annual precipitation (MAP) and to substrate-chemistry factors. Regarding the latter, we explored two models; one that included initial concentrations of water solubles, lignin, N, P, K, Ca, Mg, and Mn and one that included only lignin, N, Ca, and Mn to focus on those nutrients known to influence lignin degradation. Using backward elimination significant explanatory variables were determined. For litter decomposed in its site of origin we found the limit value to depend mainly on the initial concentration of Mn, with higher Mn concentrations resulting in higher accumulated mass loss. Thus, litter with higher Mn reached a higher limit value and left a smaller stable fraction. This is likely due to the fact that Mn is an essential component of ligninolytic enzymes important for degrading litter in the later stages of decomposition. Manganese has received little attention in decomposition studies to date. Given its significance in this synthesis, the role of Mn in influencing variation in the late stages of decomposition among ecosystems and among litters of other genera besides Pinus deserves further attention.

  • 2.
    Berg, Björn
    et al.
    Department of Forest Sciences, University of Helsinki, Helsinki, Finland .
    Erhagen, Björn
    Department of Ecology and Environmental Sciences, University of Umeå, Umeå, Sweden .
    Johansson, Maj-Britt
    University of Gävle.
    Nilsson, Mats
    Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå.
    Stendahl, Johan
    Department of Soil and Environment, Swedish University of Agricultural Sciences, Uppsala.
    Trum, Florence
    Earth and Life Institute, Universite' catolique de Louvain, Louvain-la-Neuve, Belgium .
    Vesterdal, Lars
    Department of Geosciences and Natural Resource Management, University of Copenhagen, Fredriksberg C, Denmark .
    Manganese in the litter fall-forest floor continuum of boreal and temperate pine and spruce forest ecosystems: a review2015In: Forest Ecology and Management, ISSN 0378-1127, E-ISSN 1872-7042, Vol. 358, p. 248-260, article id 15021Article, review/survey (Refereed)
    Abstract [en]

    We have reviewed the literature on the role of manganese (Mn) in the litter fall-to-humus subsystem. Available data gives a focus on North European coniferous forests. Manganese concentrations in pine (Pinus spp.) foliar litter are highly variable both spatially and temporally within the same litter species and for the genus Pinus we found a range from 0.03 to 3.7mgg-1. Concentrations were related negatively to site mean annual temperature (MAT) and annual actual evapotranspiration (AET) for pine species litter but not for that of Norway spruce (Picea abies) as a single species. Combined data for several species showed a highly significant relationship to MAT.Manganese peroxidase is an Mn-dependent enzyme, found in white-rot fungi, essential for the degradation of lignin and ligninlike compounds. The decomposition rates of lignified litter tissue (late phase) is positively related to the litter’s Mn concentration. Further, the Mn concentration is positively related to the limit value for decomposition - the higher the Mn concentration the smaller the stable litter fraction. Manganese release from decomposing litter appears at least in part to be species related. Thus was release from pine needle litter significantly faster (p<. 0.001) than that from the Mn-richer litter of Norway spruce. Over Northern Europe concentrations of total Mn in mor humus as well as extractable Mn in the mineral soil increase with decreasing MAT and over a climatic gradient the Mn concentrations in Norway spruce mor increase more with decreasing MAT than in a gradient with Scots pine. Higher Mn concentrations in humus appear to decrease its stability and result in a higher release of carbon dioxide (CO<inf>2</inf>) and dissolved organic carbon (DOC). We conclude that this may explain (i) the lower amount of carbon (C) in mor layers under Norway spruce as compared to Scots pine as well as the higher amount of C in mineral soil under spruce. The increase in nitrogen (N) concentration in humus, following N fertilization resulted in a decrease in that of Mn. We have found four cases - empirical - with negative interaction between Mn and N; (i) in pine foliar litter fall concentrations of Mn decrease with site MAT whereas those of N increase, (ii) in decomposing late-stage litter with N retarding and Mn stimulating decomposition, (iii) for the stable phase, limit values are related negatively to N and positively to Mn, and (iv) Mn concentrations in humus decrease with MAT whereas those of N increase.

  • 3.
    Berg, Björn
    et al.
    Department of Forest Ecology, University of Helsinki, Helsinki, Finland.
    Johansson, Maj-Britt
    University of Gävle.
    Liu, Chunjiang
    School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China; Shanghai Urban Forest Research Station, State Forestry Administration, Shanghai, China.
    Faituri, Mikaeel
    Department of Soils and Water, Omar AlMukhtar University, Elbeida, Libya.
    Sanborn, Paul
    Ecosystem Science and Management Program, University of Northern British Columbia, Prince George, Canada.
    Vesterdal, Lars
    Department of Geosciences and Natural Resource Management, University of Copenhagen, Frederiksberg, Denmark.
    Ni, Xiangyin
    Long-term Research Station of Alpine Forest Ecosystems, Key Laboratory of Ecological Forestry Engineering, Institute of Ecology and Forestry, Sichuan Agricultural University, Chengdu, China.
    Hansen, Karin
    IVL Swedish Environmental Research Institute, Stockholm, Sweden.
    Ukonmaanaho, Liisa
    Natural Resources Institute Finland, Helsinki, Finland.
    Calcium in decomposing foliar litter – A synthesis for boreal and temperate coniferous forests2017In: Forest Ecology and Management, ISSN 0378-1127, E-ISSN 1872-7042, Vol. 403, p. 137-144Article in journal (Refereed)
    Abstract [en]

    We have synthesized available data for calcium (Ca) dynamics in decomposing foliar litter of mainly pine (Pinus), spruce (Picea), and birch (Betula) species to determine patterns of Ca concentration with climate in newly shed litter and its dynamics in decomposing litter as well as a possible role for Ca as regards limit values. Initial Ca concentration was negatively related to mean annual precipitation (MAP) with different relationships among genera. A limited data set showed a positive relationship across species (p &lt; 0.05) to extractable Ca in soil. In paired stands, litter of both Norway spruce (Picea abies) and lodgepole pine (Pinus contorta) had higher Ca concentrations than Scots pine (Pinus silvestris), Norway spruce litter even twice as high. Relationships between initial concentrations of Ca and those of other nutrients appeared to be dominated by the positive ones to potassium (K) and magnesium (Mg) and specifically for deciduous litter there was a negative relationship to nitrogen (N). In decomposing litter, Ca concentration followed a negative quadratic (Ca = a + t − t2) function and had a maximum, which was variable. The Ca maximum concentration during decomposition was positively related to initial Ca concentration both within and among species. Separate linear relationships based on species were combined into one, in common for all investigated species and genera (R2 = 0.914, n = 63, p &lt; 0.001). Limit values for decomposition were positively related to maximum Ca concentration at p &lt; 0.05 with separate functions for pine and spruce litter. Calcium net release started directly after the incubation and was linear to accumulated mass loss of litter, giving a slope coefficient for each study. The net release rates were linear to initial Ca concentration both within and across species/genera. All studies combined gave a negative linear relationship (R2 = 0.894, n = 67, p &lt; 0.001).

  • 4.
    Berg, Björn
    et al.
    Department of Forest Sciences, University of Helsinki, Helsinki, Finland.
    Kjønaas, O. J.
    Norwegian Institute of Bioeconomy Research, Ås, Norway.
    Johansson, Maj-Britt
    University of Gävle.
    Erhagen, B.
    Department of Ecology and Environmental Science, Umeå University, Umeå, Sweden.
    Åkerblom, S.
    Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden .
    Late stage pine litter decomposition: Relationship to litter N, Mn, and acid unhydrolyzable residue (AUR) concentrations and climatic factors2015In: Forest Ecology and Management, ISSN 0378-1127, E-ISSN 1872-7042, Vol. 358, p. 41-47Article in journal (Refereed)
    Abstract [en]

    The aim of this paper is to evaluate relationships between decomposition rates of Scots pine (Pinus sylvestris) and lodgepole pine (Pinus contorta var. contorta) needle litter in the late stage of decomposition (>30% accumulated mass loss), and the progressively changing concentrations of manganese (Mn), nitrogen (N), and acid unhydrolyzable residue (AUR), as well as mean annual temperature (MAT) and mean annual precipitation (MAP). Using available long-term decomposition studies on pine needle litter in a climate gradient in Sweden, we calculated annual mass loss and related to concentrations of Mn, N, and AUR at the start of each one-year period as well as to MAT and MAP. We investigated these relationships for (i) all data on annual mass loss combined and (ii) annual mass loss for five different decomposition categories as defined by accumulated mass loss. We found highly significant, negative, and dominant relationships between annual mass loss and N (R2=0.39) and AUR (R2=0.39), a slight but significant positive relationship to Mn (R2=0.08) and a significant negative relationship to MAT (R2=0.06). The relationships were dynamic, and changed with accumulated mass loss. The rate-dampening effect of N decreased to be a rate-enhancing effect at c. 60-80% accumulated mass loss. A similar trend was found for AUR, becoming rate-enhancing at 70-80% accumulated mass loss. For Scots pine needle litter the effect of MAT on mass loss decreased with increasing accumulated mass loss and changed to a rate-dampening effect at c. 50-70% accumulated mass loss. Mn showed a stimulating effect on mass loss rate in all categories whereas MAP showed no effect in this mainly boreal climatic gradient. The current approach indicates a method for detailed studies of rate-regulating factors for litter decomposition. 

  • 5.
    Butler, Andrew
    et al.
    Institutionen för Stad och Land, Swedish University of Agricultural Sciences, Uppsala, Sweden; Faculty of Landscape and Society, Norwegian University of Life Sciences, Ås, Norway.
    Sarlöv-Herlin, Ingrid
    Institutionen för landskapsarkitektur, planering och förvaltning, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Knez, Igor
    University of Gävle, Faculty of Health and Occupational Studies, Department of Social Work and Psychology, Psychology.
    Ångman, Elin
    Institutionen för Stad och Land, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Ode Sang, Åsa
    Institutionen för landskapsarkitektur, planering och förvaltning, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Åkerskog, Ann
    FieldForest Research Institute, Uppsala, Sweden.
    Landscape identity, before and after a forest fire2018In: Landscape research, ISSN 0142-6397, E-ISSN 1469-9710, Vol. 43, no 6, p. 878-889Article in journal (Refereed)
    Abstract [en]

    Our identity is tied to where we are and how we engage with the landscapes in which we find ourselves. But what happens if the landscape which we use for our everyday life is drastically altered by a catastrophic upheaval, for example, when forest fires ravage the landscape? In this paper, interviews with individuals affected by the largest forest fire in modern Swedish history are used to exemplify our conceptualisation of how landscape identity is impacted by dramatic change. We address the phases of stability, change and progression in relation to the case. Finally, we propose that landscape identity can be utilised as a central concept for engaging with the social aspects of the impact of forest fires.

  • 6.
    Børja, Isabella
    et al.
    orwegian Forest and Landscape Institute, Ås, Norway.
    de Wit, Helene A.
    Norwegian Institute for Water Research ( NIVA), Oslo, Norway.
    Steffenrem, Arne
    orwegian Forest and Landscape Institute, Ås, Norway.
    Majdi, Hooshang
    Department of Ecology and Environmental Research, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Stand age and fine root biomass, distribution and morphology in a Norway spruce chronosequence in southeast Norway2008In: Tree Physiology, ISSN 0829-318X, E-ISSN 1758-4469, Vol. 28, no 5, p. 773-784Article in journal (Refereed)
    Abstract [en]

    We assessed the influence of stand age on fine root biomass and morphology of trees and understory vegetation in 10-, 30-, 60- and 120-year-old Norway spruce stands growing in sandy soil in southeast Norway. Fine root (< 1, 1–2 and 2–5 mm in diameter) biomass of trees and understory vegetation (< 2 mm in diameter) was sampled by soil coring to a depth of 60 cm. Fine root morphological characteristics, such as specific root length (SRL), root length density (RLD), root surface area (RSA), root tip number and branching frequency (per unit root length or mass), were determined based on digitized root data. Fine root biomass and morphological characteristics related to biomass (RLD and RSA) followed the same tendency with chronosequence and were significantly higher in the 30-year-old stand and lower in the 10-year-old stand than in the other stands. Among stands, mean fine root (< 2 mm) biomass ranged from 49 to 398 g m–2, SLR from 13.4 to 19.8 m g–1, RLD from 980 to 11,650 m m–3 and RSA from 2.4 to 35.4 m2 m–3. Most fine root biomass of trees was concentrated in the upper 20 cm of the mineral soil and in the humus layer (0–5 cm) in all stands. Understory fine roots accounted for 67 and 25% of total fine root biomass in the 10- and 120-year-old stands, respectively. Stand age had no affect on root tip number or branching frequency, but both parameters changed with soil depth, with increasing number of root tips and decreasing branching frequency with increasing soil depth for root fractions < 2 mm in diameter. Specific (mass based) root tip number and branching density were highest for the finest roots (< 1 mm) in the humus layer. Season (spring or fall) had no effect on tree fine root biomass, but there was a small and significant increase in understory fine root biomass in fall relative to spring. All morphological characteristics showed strong seasonal variation, especially the finest root fraction, with consistently and significantly higher values in spring than in fall. We conclude that fine root biomass, especially in the finest fraction (< 1 mm in diameter), is strongly dependent on stand age. Among stands, carbon concentration in fine root biomass was highest in the 30-year-old stand, and appeared to be associated with the high tree and canopy density during the early stage of stand development. Values of RLD and RSA, morphological features indicative of stand nutrient-uptake efficiency, were higher in the 30-year-old stand than in the other stands.

  • 7.
    Hedblom, Marcus
    et al.
    Department of Forest Resource Management, Swedish University of Agricultural Sciences, Umeå, Sweden; Department of Ecology, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Knez, Igor
    University of Gävle, Faculty of Health and Occupational Studies, Department of Social Work and Psychology, Psychology.
    Sang, A. Ode
    Department of Landscape Architecture, Planning and Management, Swedish University of Agricultural Sciences, Alnarp, Sweden.
    Gunnarsson, B.
    Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden.
    Evaluation of natural sounds in urban greenery: potential impact for urban nature preservation2017In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 4, no 2, article id 170037Article in journal (Refereed)
    Abstract [en]

    Most humans now live in cities and their main experience of nature is through urban greenery. An increasing number of studies show the importance of urban green spaces for wellbeing, although most of them are based on visual perception. A questionnaire examining people’s evaluations of natural sounds was answered by 1326 individuals living near one of six urban green areas of varying naturalness in the city of Gothenburg, Sweden. Women and the elderly reported greater calmness when hearing bird song and rustling leaves (and placed a higher importance on the richness of bird species) than did men, younger and middle-aged individuals. Independent of age and gender, urban woodlands (high naturalness) had higher evaluations than parks (low naturalness). Our results suggest that to increase positive experiences of urban green areas, demographic variables of gender and age should be taken into account, and settings that mimic nature should be prioritized in planning.

  • 8.
    Ji, Huawei
    et al.
    School of Agriculture and Biology and Research Centre for Low-Carbon Agriculture, Shanghai Jiao Tong University, Shanghai, China; Shanghai Urban Forest Research Station, State Forestry Administration, Beijing, China.
    Wen, Jiahao
    School of Agriculture and Biology and Research Centre for Low-Carbon Agriculture, Shanghai Jiao Tong University, Shanghai, China; Shanghai Urban Forest Research Station, State Forestry Administration, Beijing, China.
    Du, Baoming
    School of Agriculture and Biology and Research Centre for Low-Carbon Agriculture, Shanghai Jiao Tong University, Shanghai, China; Key Laboratory of Urban Agriculture (South), Ministry of Agriculture, Beijing, China.
    Sun, Ningxiao
    School of Agriculture and Biology and Research Centre for Low-Carbon Agriculture, Shanghai Jiao Tong University, Shanghai, China; Key Laboratory of Urban Agriculture (South), Ministry of Agriculture, Beijing, China.
    Berg, Björn
    University of Gävle, Faculty of Health and Occupational Studies, Department of Occupational and Public Health Sciences, Biology. Department of Forest Ecology, University of Helsinki, Helsinki, Finland.
    Liu, Chunjiang
    School of Agriculture and Biology and Research Centre for Low-Carbon Agriculture, Shanghai Jiao Tong University, Shanghai, China; Shanghai Urban Forest Research Station, State Forestry Administration, Beijing, China.
    Comparison of the nutrient resorption stoichiometry of Quercus variabilis Blume growing in two sites contrasting in soil phosphorus content2018In: Annals of Forest Science, ISSN 1286-4560, E-ISSN 1297-966X, Vol. 75, no 2, article id 59Article in journal (Refereed)
    Abstract [en]

    Key message: Foliar phosphorus (P) resorption inQuercus variabilisBlume was significantly lower at a P-rich than at a P-deficient site. Moreover, P resorption strongly decreased, and nitrogen:phosphorus and carbon:phosphorus resorption ratios increased with soil P content. This demonstrates a strong link between foliar P resorption and P content in soils, and emphasizes the importance of P resorption in leaves of trees growing in soils with contrasted P content. Context: Subtropical ecosystems are generally characterized by P-deficient soils. However, P-rich soils develop in phosphate rock areas. Aims: We compared the patterns of nutrient resorption, in terms of ecological stoichiometry, for two sites naturally varying in soil P content. Methods: The resorption efficiency (percentage of a nutrient recovered from senescing leaves) and proficiency (level to which nutrient concentration is reduced in senesced leaves) of 12 elements were determined in two oak (Q. variabilis) populations growing at a P-rich or a P-deficient site in subtropical China. Results: P resorption efficiency dominated the intraspecific variation in nutrient resorption between the two sites. Q. variabilis exhibited a low P resorption at the P-rich site and a high P resorption at the P-deficient site. Both P resorption efficiency and proficiency strongly decreased with soil P content only and were positively related to the N:P and C:P ratios in green and senesced leaves. Moreover, resorption efficiency ratios of both N:P and C:P were positively associated with soil P. Conclusion: These results revealed a strong link between P resorption and P stoichiometry in response to a P deficiency in the soil, and a single- and limiting-element control pattern of P resorption. Hence, these results provide new insights into the role of P resorption in plant adaptations to geologic variations of P in the subtropics.

  • 9.
    Mjöfors, Kristina
    et al.
    Department of Soil and Environment, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Strömgren, Monika
    Department of Soil and Environment, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Nohrstedt, Hans-Örjan
    Department of Soil and Environment, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Johansson, Maj-Britt
    University of Gävle, Vice-Chancellor's Office. Department of Soil and Environment, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Gärdenäs, Annemieke I.
    Department of Soil and Environment, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Indications that Site Preparation increases Forest Ecosystem Carbon Stocks in the Long-Term2017In: Scandinavian Journal of Forest Research, ISSN 0282-7581, E-ISSN 1651-1891, Vol. 32, no 8, p. 717-725Article in journal (Refereed)
    Abstract [en]

    Mechanical site preparation (MSP) causes a mixing disturbance of the soil, which may increase decomposition of soil organic matter and subsequent carbon (C) dioxide emissions to the atmosphere. MSP also promotes the establishment and growth of tree seedlings, and hence ecosystem C fixation. However, there are uncertainties regarding net effects of MSP on C stocks at the ecosystem scale. To assess decennial effects of MSP on ecosystem C stocks, C stocks in soil, ground vegetation and trees at three experimental forest sites with Pinus contorta, Pinus sylvestris and Picea abies in Sweden were sampled and measured ca. 25 years in a control and after three MSP treatments: disc trenching, mounding and ploughing. After 25 years, all of the MSP treatments resulted in larger ecosystem C stocks than the control treatment due to positive effects on the tree biomass C stock. The tree C stock was highest after ploughing, intermediate after mounding or disc trenching, and lowest in untreated control plots at all experimental sites. The MSP treatments did not affect the soil C stocks down to 30 cm. We recommend mounding or disc trenching to promote C sequestration as they disturb sites’ ecological, aesthetic and recreational values less than ploughing.

  • 10.
    Oostra, Swantje
    et al.
    epartment of Landscape Planning, Swedish University of Agricultural Sciences, Alnarp, Sweden.
    Majdi, Hooshang
    University of Gävle, Department of Mathematics, Natural and Computer Sciences, Ämnesavdelningen för naturvetenskap.
    Olsson, Mats
    Department of Forest Soils, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Impact of tree species on soil carbon stocks and soil acidity in southern Sweden2006In: Scandinavian Journal of Forest Research, ISSN 0282-7581, E-ISSN 1651-1891, Vol. 21, no 5, p. 364-371Article in journal (Refereed)
    Abstract [en]

    The impact of tree species on soil carbon stocks and acidity in southern Sweden was studied in a non-replicated plantation with monocultures of 67-year-old ash (Fraxinus excelsior L.), beech ( Fagus silvatica L.), elm (Ulmus glabra Huds.), hornbeam (Carpinus betulus L.), Norway spruce ( Picea abies L.) and oak ( Quercus robur L.). The site was characterized by a cambisol on glacial till. Volume-determined soil samples were taken from the O-horizon and mineral soil layers to 20 cm. Soil organic carbon (SOC), total nitrogen (TN), pH (H2O), cation-exchange capacity and base saturation at pH 7 and exchangeable calcium, magnesium, potassium and sodium ions were analysed in the soil fraction < 2 mm. Root biomass (< 5 mm in diameter) and its proportion in the forest floor and mineral soil varied between tree species. There was a vertical gradient under all species, with the highest concentrations of SOC, TN and base cations in the O-horizon and the lowest in the 10 - 20 cm layer. The tree species differed with respect to SOC, TN and soil acidity in the O-horizon and mineral soil. For SOC and TN, the range in the O-horizon was spruce > hornbeam > oak > beech > ash > elm. The pH in the O-horizon ranged in the order elm > ash > hornbeam > beech > oak > spruce. In the mineral soil, SOC and TN ranged in the order elm > oak > ash = hornbeam > spruce > beech, i.e. partly reversed, and pH ranged in the same order as for the O-horizon. It is suggested that spruce is the best option for fertile sites in southern Sweden if the aim is a high carbon sequestration rate, whereas elm, ash and hornbeam are the best solutions if the aim is a low soil acidification rate.

  • 11.
    Ortega-García, José Antonio
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Land management, GIS.
    Forest stand delineation through remote sensing and Object-Based Image Analysis2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Forest stand delineation is an essential task of forest management planning which can be time consuming and exposed to subjectivity. The increasing availability of LiDAR data and multispectral imagery offers an opportunity to improve stand delineation by means of remotely-sensed data. Under these premises, ASTER imagery and low-density LiDAR data have been used to automatically delineate forest stands in several forests of Navarra (Spain) through Object-Based Image Analysis (OBIA). Canopy cover, mean height and the canopy model have been extracted from LiDAR data and, along with VNIR ASTER bands, introduced in OBIA for forest segmentation. The outcome of segmentation has been contrasted, on the one hand, assessing segments’ inner heterogeneity. On the other, OBIA’s segments and existing stand delineations have been compared with a new method of geometrical fitting which has been ad hoc designed for this study. Results suggest that low-density LiDAR and multispectral data, along with OBIA, are a powerful tool for stand delineation. Multispectral images have a limited predicting utility for species differentiation and, in practical terms, they help to discriminate between broad-leaved, conifer and mixed stands. The performance of ASTER data, though, could be improved with higher spatial resolution VNIR imagery, specifically sub-metric VNIR orthophotos. LiDAR data, in contrast, offers a great potential for forest structure depiction. This perspective is connected with the increasingly higher resolution datasets which are to be provided by public institutions and the rapid development of drone technology. Complexity of OBIA may limit the use of this technique for small consulting firms but it is an advisable instrument for companies and institutions involved in major forestry projects.

  • 12.
    Penttinen, Markku
    et al.
    University of Gävle, Faculty of Education and Business Studies, Department of Business and Economic Studies, Business administration.
    Sekot, Walter
    University of Gävle, Faculty of Education and Business Studies, Department of Business and Economic Studies, Business administration.
    The International Financial Reporting Standards (IFRS) as implemented into the forestry accounting2016In: Advances and Challenges in Managerial Economics and Accounting: Proceedings, Wien: International Union of Forest Research Organizations , 2016, p. 91-Conference paper (Other academic)
    Abstract [en]

    Forest industries, which have shares, bonds etc. on the public market place, use the International Financial Reporting Standards (IFRS), and for the accounting of the growing stock of their forests International Accounting Standard (IAS) 41 Agriculture (EU 2009, Herbohn & Herbohn 2006). The market based fair value (FV) is the starting point of the IFRS and IAS 41. The FV uses ‘the expected net cash flows discounted at a current market-determined pre-tax rate’ if market-determined prices are not available (EU 2009, Herbohn 2009). The FV recognises the changes both in stumpage prices and the growing stock, the last of which are based on the forest management plans (FMP). The FMP relies on and benefits from the long traditions of forest inventories, growth modelling, determining optimal rotation, silvicultural recommendations etc. as well as FMP software using simulation and optimisation etc., all of which have been developed long before fair value accounting (FVA). The final felling happens in the North, say, after 80 years, which implies a certain ambiguity of the stumpage prices and discount rates.

    The paper summarizes work on this issue, preliminary ending with questionnaire-based interviews addressing IFRS-practices of Scandinavian forest companies. First, different forestry accounting traditions have been reviewed (Hogg & Jöbstl 2008, Sekot 2007). Second, theoretical bases and consequences of the FVA have been discussed (Argiles et al. 2011). Third, the pros and cons of IAS 41 as documented in the scientific literature have beenanalysed (Ayanto 2011, Elad & Herbohn 2011). Fourth, the development of stumpage prices has been studied and summarised in the first interview question. Fifth, forest regeneration and other costs have been discussed as well as addressed by questions no. two and three. Sixth, the use of this input information and the FMP are analysed and formulated as the fourth question (Penttinen & Rantala 2008, Penttinen et al. 2004). Seventh, the discount rate dilemma has been analysed and is reflected in terms of a question (Eckel et al. 2003). Even market risk and bare land accounting were inquired as well. Eight, the disclosure of the growing stock has been studied and addressed. Ninth, all closing of the books of the Scandinavian forest industries using IAS 41 have been analysed, covering the periods from 2009 to 2015 (Tornator 2016).

    The results document the use of discount rates from 5.5% to 7.5%. It is common practice to report the FV sensitivity with respect to the discount rate, stumpage price and silvicultural cost changes. The prices used are primarily medium term averages of several years, which have even been reviewed by the management and in some cases also by external experts. The typical forecasting period is ten years, and a simple price change percentageis applied thereafter, if any. Some companies estimate discount rates using weighted average cost of capital (WACC) in which the cost of equity capital is based on the capital asset pricing model (CAPM). Also in this context, external experts have been involved in some cases. Risk free interest rate is typically derived from a Euro rate. The interest requirement of the equity capital is updated semi-annually and that of the debts quarterly. Young stands are valued at cost. According to the interviews, the application of IFRS is a quite big but not an impossible burden. However, a comparison between different entities is difficult, because the standard does not provide any exact guidelines. The findings of the closing of the books and interviews are finally summarised and discussed

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