, Volume 24, Issue 2, pp 219–236 | Cite as

Tree roots as self-similar branching structures: axis differentiation and segment tapering in coarse roots of three boreal forest tree species

  • Tuomo KalliokoskiEmail author
  • Risto Sievänen
  • Pekka Nygren
Original Paper


We applied a fractal root model to the 3D architecture of the coarse root systems of Betula pendula Roth, Picea abies (L.) H. Karst., and Pinus sylvestris L. in mixed boreal forests. Our dataset consisted of 60 root systems excavated in five different mixed forest stands. We analyzed the variability of the model parameters with respect to species, site type, and different root axes. According to our results, the cross-sectional area of root segments (i.e. second power of diameter) was a suitable variable for analyzing the values of parameters of the fractal model. The parameter values varied with generation and order of root segments; the roots thus did not follow the simple fractal branching. The variation of parameters along the root axes showed the existence of a zone of rapid tapering in all tree species. The model was, with parameter values analyzed from the data, moderately capable of accounting for the main coarse root characteristics. It was important for model predictions to take into account the tapering of root segments. We conclude that, in boreal forests, tree root systems are the output of the axis-specific morphogenetic branching rules and functional adaptation to spatial heterogeneity in the soil.


Developmental stage Fractal root model Mixed stand Root architecture Site type 



We gratefully acknowledge the help of Jari Perttunen as he provided the software to read in the architectural data of roots for data analysis. We are grateful to two anonymous reviewers for their useful comments. The study was funded by the Academy of Finland (Project 210875).


  1. Berntson GM (1996) Fractal geometry, scaling, and the description of plant root architecture. In: Waisel Y, Eshel A, Kafkafi U (eds) Plant roots—the hidden half, 2nd edn. MDI Dekker, New York, pp 259–272Google Scholar
  2. Cajander AK (1949) Forest types and their significance. Acta For Fenn 56:1–71Google Scholar
  3. Collet C, Löf M, Pagès L (2006) Root system development of oak seedlings analysed using and architectural model. Effects of competition with grass. Plant Soil 279:367–383CrossRefGoogle Scholar
  4. Danjon F, Reubens B (2008) Assessing and analyzing 3D architecture of woody root systems, a review of methods and applications in tree and soil stability, resource acquisition and allocation. Plant Soil 303:1–34CrossRefGoogle Scholar
  5. Fitter AH (1991) The ecological significance of root system architecture: an economic approach. In: Atkinson D (ed) Plant root growth. An ecological perspective. Blackwell, Oxford, pp 229–243Google Scholar
  6. Fitter AH, Stickland TR (1991) Architectural analysis of plant-root systems 2. Influence of nutrient supply on architecture in contrasting plant-species. New Phytol 118(3):383–389CrossRefGoogle Scholar
  7. Fitter AH, Stickland TR, Harvey ML, Wilson GW (1991) Architectural analysis of plant-root systems 1. Architectural correlates of exploitation efficiency. New Phytol 118(3):375–382CrossRefGoogle Scholar
  8. Grime JP (2002) Plant strategies, vegetation processes and ecosystem properties, 2nd edn. Wiley, ChichesterGoogle Scholar
  9. Grime JP, Campbell BD, Mackey JML, Crick JC (1991) Root plasticity, nitrogen capture and competitive ability. In: Atkinson D (ed) Plant root growth. An ecological perspective. Blackwell, Oxford, pp 381–397Google Scholar
  10. Jourdan C, Rey H (1997) Modelling and simulation of the architecture and development of the oil-palm (Elaeis guineensis Jacq) root system 1. The model. Plant Soil 190(2):217–233CrossRefGoogle Scholar
  11. Kalliokoski T, Nygren P, Sievänen R (2008) Coarse root architecture of three boreal tree species growing in mixed stands. Silva Fenn 42(2):189–210Google Scholar
  12. MacDonald N (1983) Trees and networks in biological models. Wiley, Avon, ChichesterGoogle Scholar
  13. Mandelbrot BB (1983) The fractal geometry of nature. W.H. Freeman, New YorkGoogle Scholar
  14. Mayer DG, Butler DG (1993) Statistical validation. Ecol Model 68(1–2):21–32CrossRefGoogle Scholar
  15. Nygren P, Miaoer L, Ozier-Lafontaine H (2009) Effects of turnover and internal variability of tree root systems on modelling coarse root architecture: comparing simulations for young Populus deltoides with field data. Can J For Res 39(1):97–108CrossRefGoogle Scholar
  16. Ozier-Lafontaine H, Lecompte F, Sillon JF (1999) Fractal analysis of the root architecture of Gliricidia sepium for the spatial prediction of root branching, size and mass: model development and evaluation in agroforestry. Plant Soil 209(2):167–180CrossRefGoogle Scholar
  17. Pagès L, Vercambre G, Drouet JL, Lecompte F, Collet C, Le Bot J (2004) Root type: a generic model to depict and analyse the root system architecture. Plant Soil 258(1–2):103–119CrossRefGoogle Scholar
  18. Richardson AD, zu Dohna HZ (2005) Predicting root biomass from branching patterns of Douglas-fir root systems. Oikos 108(3):648–648 (vol 100, pg 96, 2003)Google Scholar
  19. Salas E, Ozier-Lafontaine H, Nygren P (2004) A fractal root model applied for estimating the root biomass and architecture in two tropical legume tree species. Ann For Sci 61(4):337–345CrossRefGoogle Scholar
  20. Smith DM (2001) Estimation of tree root lengths using fractal branching rules: a comparison with soil coring for Grevillea robusta. Plant Soil 229(2):295–304CrossRefGoogle Scholar
  21. Soethe N, Lehmann J, Engels C (2007) Root tapering between branching points should be included in fractal root system analysis. Ecol Model 207(2–4):363–366CrossRefGoogle Scholar
  22. Tobin B, Cermak J, Chiatante D, Danjon F, Di Orio A, Dupuy L, Eshel A, Jourdan C, Kalliokoski T, Laiho R, Nadezhdina N, Nicoll B, Pagés L, Sande-Silva J, Spannos I (2007) Towards developmental modelling of tree root systems. Plant Biosyst 141(3):481–501Google Scholar
  23. van Noordwijk M, Mulia R (2002) Functional branch analysis as tool for fractal scaling above- and belowground trees for their additive and non-additive properties. Ecol Model 149(1–2):41–51CrossRefGoogle Scholar
  24. van Noordwijk M, Purnomosidhi P (1995) Root architecture in relation to tree-soil-crop interactions and shoot pruning in agroforestry. Agrofor Syst 30:161–173CrossRefGoogle Scholar
  25. van Noordwijk M, Spek LY, Dewilligen P (1994) Proximal root diameter as predictor of total root size for fractal branching models. 1. Theory. Plant Soil 164(1):107–117CrossRefGoogle Scholar
  26. Zimmermann MH (1983) Xylem structure and the ascent of sap. Springer, Berlin, p 142Google Scholar

Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Tuomo Kalliokoski
    • 1
    Email author
  • Risto Sievänen
    • 1
  • Pekka Nygren
    • 2
  1. 1.Finnish Forest Research InstituteVantaa Research UnitVantaaFinland
  2. 2.Department of Forest EcologyUniversity of HelsinkiHelsinkiFinland

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