Anna Liisa Ruotsalainen, Juha Tuomi, Henry Väre. (2002). A model for optimal mycorrhizal colonization along altitudinal gradients. Silva Fennica vol. 36 no. 3 article id 533. https://doi.org/10.14214/sf.533

Keywords: alpine gradient; mycorrhiza; nutrient uptake kinetics; photosynthetic nutrient use efficiency

Abstract | View details | Full text in PDF | Author Info

Mycorrhizal associations are generally favourable for vascular plants in nutrient-poor conditions. Still, non-mycorrhizal plants are common in high arctic and alpine areas, which are often poor in nitrogen and phosphorus. The relative proportion of mycorrhizal plants has been found to decrease along with increasing altitude, suggesting that the advantage of the mycorrhizal symbiosis may change along an altitudinal gradient. This may be related to the environmental factors that possibly constrain the amount of photosynthesized carbon to be shared with mycorrhizal fungi. We propose a simple optimization model for root colonization by fungal symbionts and analyze the advantages of mycorrhizas in relation to the nutrient use efficiency of photosynthesis (PNUE), the kinetics of nutrient uptake and the soil nutrient levels. Our model suggests that mycorrhizas are not usually favoured at low PNUE values. At low nutrient levels, mycorrhizas may be advantageous if they have a lower threshold concentration of nutrient uptake (xmin) compared to non-mycorrhizal roots. If mycorrhizal roots have a higher maximum capacity of nutrient uptake (Vmax), mycorrhizas can be favourable for the host plant even at relatively low nutrient concentrations and at relatively low PNUE. Consequently, the possible patterns along altitudinal gradients essentially depend on PNUE. If the soil nutrient concentration is constant and PNUE decreases, the advantage of mycorrhizal symbiosis declines independently of the nutrient uptake kinetics. If PNUE remains constant and the soil nutrient concentration decreases along with increasing altitude, the emerging colonization pattern (either increasing, decreasing or intermediate) depends on the nutrient uptake kinetics. Additionally, if both PNUE and the soil nutrient concentration decrease, several patterns may emerge, depending on the nutrient uptake kinetics.

Ruotsalainen, Department of Biology, Botanical Museum, Box 3000, FIN-90014 University of Oulu, Finland E-mail: annu.ruotsalainen@oulu.fi
Tuomi, Department of Biology, Box 3000, FIN-90014 University of Oulu, Finland E-mail: jt@nn.fi
Väre, Botanical Museum, Finnish Museum of Natural History, Box 7, FIN-00014 University of Helsinki, Finland E-mail: hv@nn.fi

Click this link to register to Silva Fennica.

If you are a registered user, log in to save your selected articles for later access.

Contents alert

Your selected articles
Send to email

Eräjää S., Halme P. et al. (2010) The volume and composition of dead wood on tradi.. Silva Fennica vol. 44 no. 2 article id 150 (remove) | Edit comment

Givnish T. J., (2002) Adaptive significance of evergreen vs. deciduous.. Silva Fennica vol. 36 no. 3 article id 535 (remove) | Edit comment

Vuori E., (1913) Coniferous tree stands of the state forest “Vesi.. Acta Forestalia Fennica vol. 2 no. 1 article id 7528 (remove) | Edit comment

Huang W., (1998) Productive coexistence and gain in agroforestry .. Acta Forestalia Fennica vol. 0 no. 260 article id 7520 (remove) | Edit comment

Hildén N. A., (1934) Observations on forestry in private farms in Fin.. Acta Forestalia Fennica vol. 40 no. 33 article id 7310 (remove) | Edit comment

Laitakari E., (1935) Activities of Finnish Society of Forest Sciences.. Acta Forestalia Fennica vol. 42 no. 1 article id 7318 (remove) | Edit comment

Meurman O., (1963) Notes on ornamental trees and shrubs at the Depa.. Acta Forestalia Fennica vol. 76 no. 3 article id 7143 (remove) | Edit comment

Kangas A., Myllymäki M. et al. (2023) Understanding uncertainty in forest resources maps Silva Fennica vol. 57 no. 2 article id 22026 (remove) | Edit comment

Lee D., Siipilehto J. et al. (2021) Models for diameter distribution and tree height.. Silva Fennica vol. 55 no. 5 article id 10612 (remove) | Edit comment

Follow @SilvaFennica