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Silva Fennica 1926-1997
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Acta Forestalia Fennica
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Articles containing the keyword 'attachments'.

Category: Research article

article id 1461, category Research article
Ludmila Novitskaya, Nadezhda Nikolaeva, Natalia Galibina, Tatiana Tarelkina, Ludmila Semenova. (2016). The greatest density of parenchyma inclusions in Karelian birch wood occurs at confluences of phloem flows. Silva Fennica vol. 50 no. 3 article id 1461. https://doi.org/10.14214/sf.1461
Highlights: Dark-colored inclusions creating the figured pattern in Karelian birch wood consist of storage parenchyma cells; Their greatest density is formed above branch attachments and below forks; In these zones, the sucrose content is elevated since photoassimilate flows of the trunk and branches merge into one pathway; A high level of sucrose enhances the differentiation of parenchyma cells.

The specific pattern of the wood of Karelian birch (Betula pendula Roth var. carelica (Merckl.) Hämet-Ahti), is created mainly by dark-coloured inclusions of parenchyma tissue. Our study revealed that the greatest density of parenchyma inclusions in Karelian birch wood is observed above branch attachments to the trunk and below forks. In the place of branch attachment, phloem flows of photoassimilates (sucrose) from the branch and along the trunk merge into one pathway, causing a rise in sucrose content in tissues there. In the area below the fork, sucrose flows from two (or more) trunk axes are combined. Many studies have demonstrated that elevated sucrose level is associated with the differentiation of parenchyma. We believe that where large phloem fluxes merge a high level of sucrose promotes mass differentiation of parenchyma cells instead of fibers and vessels. As a result, the density of the figured pattern in the wood increases. The obtained data have a practical value and can be used in developing recommendations for Karelian birch cultivation.

  • Novitskaya, Forest Research Institute, Karelian Research Center, Russian Academy of Sciences, Pushkinskaya str. 11, 185910, Petrozavodsk, Russia ORCID ID:E-mail: ludnovits@rambler.ru (email)
  • Nikolaeva, Forest Research Institute, Karelian Research Center, Russian Academy of Sciences, Pushkinskaya str. 11, 185910, Petrozavodsk, Russia ORCID ID:E-mail: kar-birch@mail.ru
  • Galibina, Forest Research Institute, Karelian Research Center, Russian Academy of Sciences, Pushkinskaya str. 11, 185910, Petrozavodsk, Russia ORCID ID:E-mail: galibina@krc.karelia.ru
  • Tarelkina, Forest Research Institute, Karelian Research Center, Russian Academy of Sciences, Pushkinskaya str. 11, 185910, Petrozavodsk, Russia ORCID ID:E-mail: karelina.t.v@gmail.com
  • Semenova, Forest Research Institute, Karelian Research Center, Russian Academy of Sciences, Pushkinskaya str. 11, 185910, Petrozavodsk, Russia ORCID ID:E-mail: mi7enova@gmail.com

Category: Article

article id 5564, category Article
Jerry Johansson. (1995). Backhoe loaders as base machines in logging operations. Silva Fennica vol. 29 no. 4 article id 5564. https://doi.org/10.14214/sf.a9215

Time studies and an ergonomic assessment were carried out in logging operations for three logging machines based on backhoe loader chassis. The time studies were completed with a follow-up study of one backhoe loader-based single-grip harvester. The studies indicated a productivity at the same level as that of specialized Nordic logging machines. Ergonomics also proved to be good. Mean ground pressure exerted by the backhoe loader-based logging machines was little higher than for some of the conventional Nordic single-grip harvesters to which it was compared. The ability of the machines to operate in the terrain was also good, even in rough terrain.

These machines can also be used for other jobs, such as ditch digging, road building and road maintenance. The machines then function more as carriers for attachments rather than custom-built backhoe loaders. By more careful planning of operations, the machines can be used to a higher degree and more effectively. The relatively low investment cost compared to many custom-built Nordic logging machines also contributes to a reduction of operating costs.

  • Johansson, ORCID ID:E-mail:

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