Current issue: 58(2)

Under compilation: 58(3)

Scopus CiteScore 2021: 2.8
Scopus ranking of open access forestry journals: 8th
PlanS compliant
Select issue
Silva Fennica 1926-1997
1990-1997
1980-1989
1970-1979
1960-1969
Acta Forestalia Fennica
1953-1968
1933-1952
1913-1932

Articles by Pedro J. Aphalo

Category : Research article

article id 328, category Research article
Pedro J. Aphalo, Markku Lahti, Tarja Lehto, Tapani Repo, Aino Rummukainen, Hannu Mannerkoski, Leena Finér. (2006). Responses of silver birch saplings to low soil temperature. Silva Fennica vol. 40 no. 3 article id 328. https://doi.org/10.14214/sf.328
Keywords: biomass; Betula pendula; photosynthesis; electrical impedance; mineral nutrients; soil temperature; stomatal conductance; water relations
Abstract | View details | Full text in PDF | Author Info
Two-year-old silver birch (Betula pendula) saplings were grown for a third growing season in controlled-environment rooms (dasotrons) at three soil temperatures (5, 10, and 20 °C). All trees grew the first flush of leaves, but the growth of the second flush was almost completely inhibited at the two lower temperatures. The dry weight of the second-flush leaves was 50 times larger at 20 °C than at 5 and 10 °C, with about 100 times more nitrogen. Root growth was less affected than shoot growth. Chlorophyll content, net assimilation rate and stomatal conductance were lower at low soil temperatures. The value of the cytoplasm resistance estimated from the electric impedance spectra was lower at 5 °C than at 10 or 20 °C. Leaf water potential was highest at the lowest soil temperature, and intercellular carbon dioxide concentration was only slightly lower in saplings growing in cooler soil. We conclude that the effect of long-term exposure to cold soil on net assimilation and growth was not caused by stomatal closure alone. It is likely to be additionally mediated by the limited nitrogen acquisition at the low soil temperatures, and perhaps additionally by some other factor. As the growth depression of aboveground parts in response to low soil temperature was more significant in silver birch than what has earlier been found in conifers, the relative changes in air and soil temperature may eventually determine whether birch will become more dominant in boreal forests with climate change.
  • Aphalo, University of Helsinki, Department of Biological and Environmental Sciences E-mail: pja@nn.fi
  • Lahti, The Finnish Forest Research Institute E-mail: ml@nn.fi
  • Lehto, University of Joensuu, Faculty of Forestry, Box 111, FI-80101 Joensuu, Finland E-mail: tarja.lehto@joensuu.fi (email)
  • Repo, The Finnish Forest Research Institute E-mail: tr@nn.fi
  • Rummukainen, University of Joensuu, Faculty of Forestry, Box 111, FI-80101 Joensuu, Finland E-mail: ar@nn.fi
  • Mannerkoski, University of Joensuu, Faculty of Forestry, Box 111, FI-80101 Joensuu, Finland E-mail: hm@nn.fi
  • Finér, The Finnish Forest Research Institute E-mail: lf@nn.fi
article id 532, category Research article
Pedro J. Aphalo, Anna W. Schoettle, Tarja Lehto. (2002). Leaf life span and the mobility of “non-mobile” mineral nutrients – the case of boron in conifers. Silva Fennica vol. 36 no. 3 article id 532. https://doi.org/10.14214/sf.532
Keywords: needle age; conifers; model; boron; leaf life span; nutrient mobility; toxicity
Abstract | View details | Full text in PDF | Author Info
Nutrient conservation is considered important for the adaptation of plants to infertile environments. The importance of leaf life spans in controlling mean residence time of nutrients in plants has usually been analyzed in relation to nutrients that can be retranslocated within the plant. Longer leaf life spans increase the mean residence time of all mineral nutrients, but for non-mobile nutrients long leaf life spans concurrently cause concentrations in tissues to increase with leaf age, and consequently may reduce non-mobile nutrient use efficiency. Here we analyze how the role of leaf life span is related to the mobility of nutrients within the plant. We use optimality concepts to derive testable hypotheses, and preliminarily test them for boron (B), a nutrient for which mobility varies among plant species. We review published and unpublished data and use a simple model to assess the quantitative importance of B retranslocation for the B budget of mature conifer forests and as a mechanism for avoiding toxicity.
  • Aphalo, Faculty of Forestry, University of Joensuu, P.O. Box 111, FIN-80101 Joensuu, Finland; Current address Department of Biological and Environmental Science, University of Jyväskylä, P.O. Box 35, FIN-40351 Jyväskylä, Finland. E-mail: pedro.aphalo@jyu.fi (email)
  • Schoettle, Rocky Mountain Research Station, 240 West Prospect Road, Fort Collins, CO 80526, USA E-mail: aws@nn.us
  • Lehto, Faculty of Forestry, University of Joensuu, P.O. Box 111, FIN-80101 Joensuu, Finland E-mail: tl@nn.fi

Register
Click this link to register to Silva Fennica.
Log in
If you are a registered user, log in to save your selected articles for later access.
Contents alert
Sign up to receive alerts of new content
Your selected articles
Send to email
Multamäki S. E., (1923) Studies on the growth of drained peatlands in Fi.. Acta Forestalia Fennica vol. 27 no. 1 article id 7094 (remove) | Edit comment
Kupila-Ahvenniemi S., Hankonen S. et al. (1974) Experiments on the determination of certain elem.. Silva Fennica vol. 8 no. 3 article id 4904 (remove) | Edit comment
Räsänen P. K., (1970) The effect of lifting date, packing, storing and.. Acta Forestalia Fennica vol. 0 no. 112 article id 7546 (remove) | Edit comment
Nyyssönen A., (1950) Comparative study on structure and development o.. Silva Fennica vol. no. 68 article id 4600 (remove) | Edit comment
Lassila I., (1929) The influence of forest site type on the weight .. Acta Forestalia Fennica vol. 36 no. 1 article id 7259 (remove) | Edit comment
Varis S., Pakkanen A. et al. (2009) The extent of south-north pollen transfer in Fin.. Silva Fennica vol. 43 no. 5 article id 168 (remove) | Edit comment
Uotila A., (1990) Infection of pruning wounds in Scots pine by Pha.. Acta Forestalia Fennica vol. 0 no. 215 article id 7662 (remove) | Edit comment
Kaitera J., (2000) Analysis of Cronartium flaccidum lesion developm.. Silva Fennica vol. 34 no. 1 article id 641 (remove) | Edit comment
Päivänen J., (1974) The effect of ditch spacing and furrowing on dep.. Silva Fennica vol. 8 no. 4 article id 4908 (remove) | Edit comment
Mäkinen H., (1997) Possibilities of competition indices to describe.. Silva Fennica vol. 31 no. 1 article id 5608 (remove) | Edit comment
Laakkonen A., Hujala T. et al. (2022) Defining the systemic development of the Finnish.. Silva Fennica vol. 56 no. 2 article id 10599 (remove) | Edit comment
Heliövaara K., Väisänen R. (1989) Invertebrates of young Scots pine stands near th.. Silva Fennica vol. 23 no. 1 article id 5368 (remove) | Edit comment
Smolander H., Kellomäki S. et al. (1990) The effect of nitrogen concentration on needle p.. Silva Fennica vol. 24 no. 1 article id 5414 (remove) | Edit comment
Liski J., (1995) Variation in soil organic carbon and thickness o.. Silva Fennica vol. 29 no. 4 article id 5561 (remove) | Edit comment