Browsing by Subject "silviculture"

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  • Myllyviita, Tanja; Sironen, Susanna; Saikku, Laura; Holma, Anne; Leskinen, Pekka; Palme, Ulrika (2019)
    Journal of Cleaner Production 236: 117641
    Impacts of bioeconomy on climate have been much discussed, but less attention has been given to biodiversity deterioration. One approach to assess biodiversity impacts is Life Cycle Assessment (LCA). Finland is a forested country with intensive forest industries, but only coarse biodiversity LCA methods are available. The aim of this study was to further develop and apply approaches to assess the biodiversity impacts of wood use in Finland. With the species richness approach (all taxons included), biodiversity impacts were higher in Southern than in Northern Finland but impacts in Southern and Northern Finland were lower when mammals, birds and molluscs were included. With the ecosystem indicators approach, if the reference situation were forest in its natural state, biodiversity impacts were higher than in the case where the initial state of forest before final felling was used to derive biodiversity loss. In both cases, the biodiversity impacts were higher in Northern Finland. These results were not coherent as the model applying species richness data assesses biodiversity loss based on all species, whereas the ecosystem indicators approach considers vulnerable species. One limitation of the species richness approach was that there were no reliable datasets available. In the ecosystem indicators approach, it was noticed that the biodiversity of managed Finnish forests is substantially lower than in natural forests. Biodiversity LCA approaches are highly sensitive to reference states, applied model and data. It is essential to develop approaches capable of comparing biodiversity impacts of forest management practices, or when looking at multiple environmental impacts simultaneously with the LCA framework.
  • Kuglerová, Lenka; Jyväsjärvi, Jussi; Ruffing, Claire; Muotka, Timo; Jonsson, Anna; Andersson, Elisabet; Richardson, John S. (American Geophysical Union, 2020)
    Water Resources Research 56 9 (2020)
    Forested riparian buffers are recommended to mitigate negative effects of forest harvesting on recipient freshwater ecosystems. Most of the current best practices of riparian buffer retention aim at larger streams. Riparian protection along small streams is thought to be lacking; however, it is not well documented. We surveyed 286 small streams flowing through recent clearcuts in three timber-producing jurisdictions—British Columbia, Canada (BC), Finland, and Sweden. The three jurisdictions differed in riparian buffer implementation. In BC, forested buffers are not required on the smallest streams, and 45% of the sites in BC had no buffer. The average (±SE) width of voluntarily retained buffers was 15.9 m (±2.1) on each side of the stream. An operation-free zone is mandatory around the smallest streams in BC, and 90% of the sites fulfilled these criteria. Finland and Sweden had buffers allocated to most of the surveyed streams, with average buffer width of 15.3 m (±1.4) in Finland and 4 m (±0.4) in Sweden. Most of the streams in the two Nordic countries had additional forestry-associated impairments such as machine tracks, or soil preparation within the riparian zone. Riparian buffer width somewhat increased with stream size and slope of the riparian area, however, not in all investigated regions. We concluded that the majority of the streams surveyed in this study are insufficiently protected. We suggest that a monitoring of forestry practices and revising present forestry guidelines is needed in order to increase the protection of our smallest water courses.
  • Saksa, Timo; Uusitalo, Jori; Lindeman, Harri; Häyrynen, Esko; Kulju, Sampo; Huuskonen, Saija (2021)
    Precision forestry-i.e., the division of a stand to smaller units and managing of the stand at a micro-stand level-provides new possibilities to increase forest growth, arrange forest stand structure and enhance forest health. In the regeneration phase by adjusting the tree species selection, soil preparation, intensity of regeneration measures (method, planting density, and material), and young stand management procedures according to precise information on soil properties (e.g., site fertility, wetness, and soil type) and microtopography will inevitably lead to an increase in growth of the whole stand. A new approach to utilizing harvester data to delineate micro-stands inside a large forest stand and to deciding the tree species to plant for each micro-stand was piloted in central Finland. The case stands were situated on Finsilva Oyj forest property. The calculation of the local growth (m(3)/ha/year) for each 16 x 16-m grid cell was based on the height of the dominant trees and the stand age of the previous tree generation. Tree heights and geoinformation were collected during cutting operation as the harvester data, and the dominant height was calculated as the mean of the three largest stems in each grid cell. The stand age was obtained from the forest management plan. The estimated local growth (average of nine neighboring grid cells) varied from 3 to 14 m(3)/ha/year in the case stands. When creating micro-stands, neighboring grid cells with approximately the same local growth were merged. The minimum size for an acceptable micro-stand was set to 0.23 ha. In this case study, tree species selection (Scots pine or Norway spruce) was based on the mean growth of each micro-stand. Different threshold values, varying from 6 to 8 m(3)/ha/year, were tested for tree species change, and they led to different solutions in the delineation of micro-stands. Further stand development was simulated with the Motti software and the net present values (NPVs (3%)) for the next rotation were estimated for different micro-stand solutions. The mixed Norway spruce-Scots pine stand structure never produced a clearly economically inferior solution compared to the single species stand, and in one case out of six, it provided a distinctly better solution in terms of NPV (3%) than the single species option did. Our case study showed that this kind of method could be used as a decision support tool at the regeneration phase.
  • Kalela, Erkki K. (Suomen metsätieteellinen seura, 1949)
  • Saarinen, Ninni; Kankare, Ville; Huuskonen, Saija; Hynynen, Jari; Bianchi, Simone; Yrttimaa, Tuomas; Luoma, Ville; Junttila, Samuli; Holopainen, Markus; Hyyppae, Juha; Vastaranta, Mikko (2022)
    Trees adapt to their growing conditions by regulating the sizes of their parts and their relationships. For example, removal or death of adjacent trees increases the growing space and the amount of light received by the remaining trees enabling their crowns to expand. Knowledge about the effects of silvicultural practices on crown size and shape and also about the quality of branches affecting the shape of a crown is, however, still limited. Thus, the aim was to study the crown structure of individual Scots pine trees in forest stands with varying stem densities due to past forest management practices. Furthermore, we wanted to understand how crown and stem attributes and also tree growth affect stem area at the height of maximum crown diameter (SAHMC), which could be used as a proxy for tree growth potential. We used terrestrial laser scanning (TLS) to generate attributes characterizing crown size and shape. The results showed that increasing stem density decreased Scots pine crown size. TLS provided more detailed attributes for crown characterization compared with traditional field measurements. Furthermore, decreasing stem density increased SAHMC, and strong relationships (Spearman's correlations > 0.5) were found between SAHMC and crown and stem size and also stem growth. Thus, this study provided quantitative and more comprehensive characterization of Scots pine crowns and their growth potential. The combination of a traditional growth and yield study design and 3D characterization of crown architecture and growth potential can open up new research possibilities.
  • Vasander, Harri; Lindholm, Tapio (Suomen metsätieteellinen seura, 1985)
  • Raulo, Jyrki (Suomen metsätieteellinen seura, 1978)
  • Mann, Carsten; Loft, Lasse; Hernández-Morcillo, Mónica; Primmer, Eeva; Bussola, Francesca; Falco, Enzo; Geneletti, Davide; Dobrowolska, Ewelina; Grossmann, Carol M.; Bottaro, Giorgia; Schleyer, Christian; Kluvankova, Tatiana; Garcia, Gino; Lovrić, Marko; Torralba, Mario; Plieninger, Tobias; Winkel, Georg (Elsevier Science, 2022)
    Environmental science and policy
    This paper analyses the occurrence of governance innovations for forest ecosystem service (FES) provision in the forestry sector in Europe and the factors that influence innovation development. Based on a European-wide online survey, public and private forest owners and managers representing different property sizes indicate what type of governance innovation activities they engage in, and why. To investigate forestry innovations as systems, the analysis focuses on biophysical, social and technical factors influencing innovation development. The results of our exploratory quantitative analysis show that most innovation activities identified are largely oriented towards biomass production. Accordingly, most forest owners implement efficiency-driven optimisation strategies for forest management and technological improvement for provisioning service supply, to generate income. In contrast, the provision of regulating and cultural services is not yet a prominent part of forestry innovation activities. Reasons are rooted in a market-oriented economic rationale focusing on timber production, a lack of financial resources to compensate for other FES provisions or institutions to provide backup and security to forest owners and managers for engaging in innovation development. Given that the provision of a wide range of FES is a politically well-established objective for forest management in Europe, a strategy is needed that helps to align actors and sectors for supporting and co-financing related forest management approaches and business models. The current revision of the forest related policy framework on EU level under the EU Green deal poses a window of opportunity for better fostering novel governance approaches for more sustainable FES provision.
  • Kojola, Soili; Penttilä, Timo; Laiho, Raija (2004)
    Drained peatlands in northern Europe comprise more than 10 million ha of forestland and thus constitute a considerable production potential in forestry. Much of this area consists of stands dominated by Scots pine and close to maturity regarding commercial thinning. The trees within these stands typically vary in terms of age, size, and growth rate. The impacts of silvicultural cuttings on these uneven-structured stands are inadequately known. We simulated the impacts of a control regime with no thinnings, and three different thinning regimes, involving different thinning intensities, on the development of fifteen pine-dominated stands in Finland. The simulations started from the first thinnings and were continued until regeneration maturity. The predicted total yields ranged from 244 to 595 m3ha-1, depending on site and thinning regime. The highest total yields were observed for the control regime in which 18-38% of the yield was, however, predicted to self-thin by the end of the simulation. Thus, the differences in the yields of merchantable wood were fairly small among the compared regimes. However, the regimes involving thinnings generally needed less time than the control regime to reach regeneration maturity. The mean annual increment of total stem volume was at its highest in the control regime. The highest mean annual increment of merchantable wood was obtained in the regime involving two moderate thinnings, but excluding the most low-productive sites where thinnings did not increase the yield of merchantable wood.
  • Orsi, Francesco; Ciolli, Marvo; Primmer, Eeva; Varumo, Liisa; Geneletti, Davide (Butterworth Scientific, 2020)
    Land Use Policy 99 : 104840
    Forests cover about 40 % of the European Union (EU), providing a wide spectrum of invaluable ecosystem services to more than half a billion people. In order to protect and harness this crucial asset, EU policies are advancing multifunctional management. This study lays a basis for such an effort by mapping the supply of key forest ecosystem services (FES) across the entire EU: wood, water supply, erosion control, pollination, habitat protection, soil formation, climate regulation and recreation. To further support the operationalization of multifunctionality and targeting of policies, our analysis delineates hotspots, assesses synergies and tradeoffs, and identifies spatial bundles. We generated maps at 1-km resolution starting from existing datasets through simple modelling (Tier 1). Out of these maps, we denoted the highest supplying pixels (i.e. top 20 %) as hotspots, and performed correlation analysis to detect synergies and tradeoffs. Finally, we used cluster analysis to identify FES bundles. Our analysis shows that hotspots of single FES are spread across the entire EU and that forests of mountain regions and Central Europe (particularly France, Germany, Slovakia) supply significant amounts of multiple FES. The cluster analysis resulted in four bundles: “balanced” in the northeast, “wood & water” in the center, “soil carbon” in the north and “rural-recreational” in the south. While a purely quantitative analysis of the produced maps may be misleading because of the strong links between FES supply and climatic and socio-economic conditions, overlaying hotspots and bundles with administrative layers can be a first step to inform about the role of different countries and regions in securing the sustainable supply of European FES.
  • Kallioniemi, Paula (Helsingfors universitet, 2012)
    Tending of seedling stands and improvement of young stands are important steps in wood produc-tion, but they are often postponed or even neglected primarily due to high expenses and poor availability of labour. Machine tending of young stands requires special equipment and appropri-ately suited devices, restricting the method's feasibility to larger stands. For the present, clea-ring and thinning of young stands is mainly accomplished manually using a clearing saw due to lower cost of manual work compared with machine tending. Mechanized pre-commercial thinning further requires that strip roads must be opened, which will reduce the number of growing trees, resulting in diminished area for wood production. Trunk and root damages are a frequent phenomenon and furthermore the terrain can sustain damage. Dam-ages in standing crop and soil can reduce timber output during forest rotation time. The negative contribution of strip roads on timber output and poor forest health should be countered in devel-oping machine tending. The need for the development of machine tending and its benefits increas-es with receding availability of labour. This study focuses on the influence on timber production and trunk damages by a forestry vehicle equipped with a MenSe clearing head. The emphasis lies on examining strip roads and damages in young stands. In addition to conclusions from forest measurements, literature search was applied in studying the effects of machine tending on timber output. The corollary influence of strip roads on future timber output requires further research. The study observes a 10 % decrease in surface area resulting from laying strip roads for mechanized pre-commercial thinning. Trunk damages were present on average in 5 % of the remaining trees. Growth impeding trees surrounding growing trees amounted to 250 trees per hectare and need-lessly removed trees about 90 per hectare. The consumption of working time averaged 8,4 hours per hectare and hourly output 0,12 hectare on all sites. Nonnegligent divergencies in drivers regard-ing efficiency and procedure were observed. Attending to the education, motivation, advicement and supervision of the driver will be worthwhile in the future. Circumstances surrounding both the driver and the forest machine present a challenge in develop-ing the cost-efficiency and labour resultant of mechanized pre-commercial thinning. In the future more alternatives for wood production chain should be considered for research, for instance the possibility of entirely abandoning pre-commercial thinning after the preliminary cleaning of seed-ling stands with an uprooter, subsequently leading to energy wood thinning or first thinning.
  • Kellomäki, Seppo; Hänninen, Heikki; Kolström, Taneli (Suomen metsätieteellinen seura, 1988)
  • Varhimo, Antero; Kojola, Soili; Penttilä, Timo; Laiho, Raija (2003)
    The inherent structural dynamics of drained peatland forests may result in a great variation in various wood and fi ber properties. We examined variation in fi ber and pulp properties i) among stands, ii) among trees within stands, and iii) within trees in young stands dominated by Scots pine (Pinus sylvestris L.). The stands, selected to cover a maximal range of the potential variation, were all at a stage of development where the fi rst commercial thinnings would be feasible. Differences in the processability of the thinning removals were small. In similar kraft cooking conditions, a 5-unit variation in the kappa number of unbleached pulp was observed among the stands. Stand origin had no effect on pulp bleaching. The wood formed prior to drainage had a higher density, shorter fi bers, was slightly slower delignifi ed by cooking, and its yield was slightly lower than that of post-drainage wood. These properties, except for high density, are typical for juvenile wood in general, and at stand level they did not correlate with the proportion of pre-drainage wood. When the variation in fi ber and pulp properties was broken down into its components, most of it was derived from tree-level in all the cases. On average, the fi ber and pulp properties did not differ from those observed for fi rst-thinning pulpwood from upland sites. Consequently, peatland-grown pulpwood may be mixed with other pulpwood in industrial processes. It would probably be best suited as the raw material for pulps with high bonding requirements, e.g. in the top ply of multi-ply board grades or in some specialty grades.
  • Mikola, Peitsa; Kangas, Esko; Heikurainen, Leo (Suomen metsätieteellinen seura, 1959)
  • Ervasti, Seppo; Heikinheimo, Lauri; Holopainen, Viljo; Kuusela, Kullervo; Sirén, Gustaf (Suomen metsätieteellinen seura, 1965)
  • Persson, Johannes; Thorén, Henrik; Olsson, Lennart (2018)
    Interdisciplinary research in the fields of forestry and sustainability studies often encounters seemingly incompatible ontological assumptions deriving from natural and social sciences. The perceived incompatibilities might emerge from the epistemological and ontological claims of the theories or models directly employed in the interdisciplinary collaboration, or they might be created by other epistemological and ontological assumptions that these interdisciplinary researchers find no reason to question. In this paper we discuss the benefits and risks of two possible approaches, Popperian optimism and Kuhnian pessimism, to interdisciplinary knowledge integration where epistemological and ontological differences between the sciences involved can be expected.
  • Saarinen, Ninni; Calders, Kim; Kankare, Ville; Yrttimaa, Tuomas; Junttila, Samuli; Luoma, Ville; Huuskonen, Saija; Hynynen, Jari; Verbeeck, Hans (2021)
    Tree functional traits together with processes such as forest regeneration, growth, and mortality affect forest and tree structure. Forest management inherently impacts these processes. Moreover, forest structure, biodiversity, resilience, and carbon uptake can be sustained and enhanced with forest management activities. To assess structural complexity of individual trees, comprehensive and quantitative measures are needed, and they are often lacking for current forest management practices. Here, we utilized 3D information from individual Scots pine (Pinus sylvestris L.) trees obtained with terrestrial laser scanning to, first, assess effects of forest management on structural complexity of individual trees and, second, understand relationship between several tree attributes and structural complexity. We studied structural complexity of individual trees represented by a single scale-independent metric called "box dimension." This study aimed at identifying drivers affecting structural complexity of individual Scots pine trees in boreal forest conditions. The results showed that thinning increased structural complexity of individual Scots pine trees. Furthermore, we found a relationship between structural complexity and stem and crown size and shape as well as tree growth. Thus, it can be concluded that forest management affected structural complexity of individual Scots pine trees in managed boreal forests, and stem, crown, and growth attributes were identified as drivers of it.
  • Lindholm, Tapio; Vasander, Harri (Suomen metsätieteellinen seura, 1987)