A new model for root growth in soil with macropores
- 765 Downloads
Background and aims
The use of standard dynamic root architecture models to simulate root growth in soil containing macropores failed to reproduce experimentally observed root growth patterns. We thus developed a new, more mechanistic model approach for the simulation of root growth in structured soil.
In our alternative modelling approach, we distinguish between, firstly, the driving force for root growth, which is determined by the orientation of the previous root segment and the influence of gravitropism and, secondly, soil mechanical resistance to root growth. The latter is expressed by its inverse, soil mechanical conductance, and treated similarly to hydraulic conductivity in Darcy’s law. At the presence of macropores, soil mechanical conductance is anisotropic, which leads to a difference between the direction of the driving force and the direction of the root tip movement.
The model was tested using data from the literature, at pot scale, at macropore scale, and in a series of simulations where sensitivity to gravity and macropore orientation was evaluated.
Qualitative and quantitative comparisons between simulated and experimentally observed root systems showed good agreement, suggesting that the drawn analogy between soil water flow and root growth is a useful one.
KeywordsMacropores Root architecture model Root growth direction R-SWMS
Funding by German Research Foundation within the Research Unit DFG PAK 888 is gratefully acknowledged. The James Hutton Institute receives funding from the Scottish Government. We also thank Richard Stirzaker and John Passioura (CSIRO) for helpful correspondence concerning experimental methods.
- Athmann M, Huang N, Kautz T, Köpke U (2014) Biopore characterization with in situ endoscopy: Influence of earthworms on carbon and nitrogen contents. In: RGA U (ed) 4th ISOFAR Scientific Conference, IstanbulGoogle Scholar
- Bear J (2013) Dynamics of fluids in porous media. Courier CorporationGoogle Scholar
- Gao W, Hodgkinson L, Jin K, Watts CW, Ashton RW, Shen J, Ren T, Dodd IC, Binley A, Phillips AL (2016a) Deep roots and soil structure. Plant Cell Environ. doi: 10.1111/pce.12684
- Gregory PJ (2008) Plant roots: growth, activity and interactions with the soil. John Wiley & Sons.Google Scholar
- Gruwel ML (2014) In situ magnetic resonance imaging of plant roots. Vadose Zone J 13Google Scholar
- Kautz T, Köpke U (2009) Assessing the root-soil contact in biopores. International Symposium 'Root Research and Applications', Vienna, AustriaGoogle Scholar
- Kautz T, Amelung W, Ewert F, Gaiser T, Horn R, Jahn R, Javaux M, Kemna A, Kuzyakov Y, Munch J, Patzold S, Peth S, Scherer H, Schloter M, Schneider H, Vanderborght J, Vetterlein D, Walter A, Wiesenberg G, Kopke U (2013a) Nutrient acquisition from arable subsoils in temperate climates: a review. Soil Biol Biochem 57:1003–1022. doi: 10.1016/j.soilbio.2012.09.014 CrossRefGoogle Scholar
- Leue M, Gerke HH (2016) Roughness of biopores and cracks in Bt-horizons assessed by confocal laser scanning microscopy. J Plant Nutr Soil Sci. doi: 10.1002/jpln.201600016
- Lust M (2001) Quaternionen- mathematischer Hintergrund und ihre Interpretation als Rotationen. In: Koblenz-Landau U (ed)Google Scholar
- Nagel K, Putz A, Gilmer F, Heinz K, Fischbach A, Pfeifer J, Faget M, Bloßfeld S, Ernst M, Dimaki C, Kastenholz B, Kleinert A, Galinski A, Scharr H, Fiorani F, Schurr U (2012) GROWSCREEN-Rhizo is a novel phenotyping robot enablign simultaneous measruements of root and shoot growth for pkants grown in soil-filled rhizotrons. Funct Plant Biol 39:891–904CrossRefGoogle Scholar
- Sammartino S, Lissy A-S, Bogner C, Van Den Bogaert R, Capowiez Y, Ruy S, Cornu S (2015) Identifying the functional macropore network related to preferential flow in structured soils. Vadose Zone J 14Google Scholar
- Stingaciu L, Schulz H, Pohlmeier A, Behnke S, Zilken H, Javaux M, Vereecken H (2013) In situ root system architecture extraction from magnetic resonance imaging for water uptake modeling. Vadose Zone J 12Google Scholar
- Tracy S (2013) The response of root system architecture to soil compaction. Philosophy. NottinghamGoogle Scholar
- Vereecken H, Schnepf A, Hopmans JW, Javaux M, Or D, Roose T, Vanderborght J, Young M, Amelung W, Aitkenhead M, Allison SD, Assouline S, Baveye P, Berli M, Brüggemann N, Finke P, Flury M, Gaiser T, Govers G, Ghezzehei T, Hallett PD, Hendricks, Franssen HJ, Heppel J, Horn R, Huisman J, Jacques D, Jonard F, Kollet S, Lafolie F, Lamorski K, Leitner D, Mc Bratney A, Minasny B, Montzka C, Nowak W, Pachepsky Y, Padarian J, Romano N, Roth K, Rothfuss Y, Rowe E, Schwen A, Simunek J, Tiktak A, Van Dam J, van der Zee S, Vogel H, Vrugt J, Wöhling T, Young I (2016) Modeling soil processes: review, key challenges, and new perspectives. Vadose Zone J 15Google Scholar