Abstract
The allocation of resources among roots and shoots represents the largest flux of resources within a plant and therefore should have been selected to maximize benefits to plants. Yet, it is unclear why some species like temperate grasses have such high root length density (RLD). Either the slow rate of diffusion of inorganic N in soils or interplant competition could explain the high RLD of temperate grasses. Using a fine-scale model of nutrient dynamics in the soil and plant growth, a cost–benefit approach was used to assess optimal allocation rates for plants that accounted for value of both carbon and nitrogen. In the absence of interplant competition, resource benefits are maximized with very little root length except in extremely dry soils for ammonium. In the presence of a competitor, optimal allocation of N to roots is much greater and increases as ability of competitors to produce root length increase. Competition for inorganic nitrogen generates a classic aspect of the tragedy of the commons, the “race for fish”, where plants must allocate more resources to acquisition of the limiting resource than is optimal for plants in the absence of competition. As such, nutrient competition needs to be directly addressed when understanding plant- and ecosystem-level resource fluxes as well as the evolution of root systems.
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References
Aerts R, Chapin FS III (2000) The mineral nutrition of wild plants revisited: re-evaluation of processes and patterns. Adv Ecol Res 30:1–67
Andrews R, Newman EI (1979) Root density and competition for nutrients. Oecolog Plantar 5:319–334
Anten NPR, Hirose T (2001) Limitations on photosynthesis of competing individuals in stands and the consequences for canopy structure. Oecologia 129:186–196
Atkin OK, Botman B, Lambers H (1996) The causes of inherently slow growth in alpine plants: an analysis based on the underlying carbon economies of alpine and lowland Poa species. Funct Ecol 10:698–707
Bloom AJ, Chapin FS III, Mooney HA (1985) Resource limitation in plants – an economic analogy. Annu Rev Ecol Syst 16:363–392
Bouma TJ, Yanai RD, Elkin AD, Hartmond U, Flores-Alva DE, Eissenstat DM (2001) Estimating age-dependent costs and benefits of roots with contrasting life span: comparing apples and oranges. New Phytol 150:685–695
Cannell MGR, Thornley JHM (2000) Modelling the components of plant respiration: some guiding principles. Ann Bot 85:45–54
Chapin FS III (1991) Effects of multiple environmental stresses on nutrient availability and use. In: Mooney HA, Winner WE, Pell EJ (eds) Response of plants to multiple stresses. Academic Press, San Diego, pp 67–88
Craine J, Bond W, Lee W, Reich P, Ollinger S 2003a The resource economics of chemical and structural defenses across nitrogen supply gradients. Oecologia 442:547–556
Craine JM, Fargione J, Sugita S (2005) Supply pre-emption, not concentration reduction, is the mechanism of competition for nutrients. New Phytol 166:933–940
Craine JM, Tilman DG, Wedin DA, Reich PB, Tjoelker MJ, Knops JMH (2002) Functional traits, productivity and effects on nitrogen cycling of 33 grassland species. Funct Ecol 16:563–574
Craine JM, Wedin DA, Chapin FS III, Reich PB (2003b) Development of grassland root systems and their effects on ecosystem properties. Plant Soil 250:39–47
Craine JM, Wedin DA, Chapin FS III, Reich PB (2003c) Relationship between the structure of root systems and resource use for 11 North American grassland plants. Plant Ecol 165:85–100
Donald CM (1981) Competitive plants, communal plants, and yield in wheat crops. In: Evans LT, Peacock WJ (eds) Wheat science – today and tomorrow. Cambridge University Press, pp 223–247
Eissenstat D, Yanai R (1997) The ecology of root lifespan. Adv Ecol Res 27:2–60
Falster DS, Westoby M (2003) Plant height and evolutionary games. Trends Ecol Evol 18:337–343
Gersani M, Brown JS, O’Brien EE, Maina GM, Abramsky Z (2001) Tragedy of the commons as a result of root competition. J Ecol 89:660–669
Hunik J, Bos C, van den Hoogen M, De Gooijer C, Tramper J (1994) Co-immobilized Nitrosomonas europaea and Nitrobacter agilis cells: validation of a dynamic model for simultaneous substrate conversion and growth in k-carrageenan gel beads. Biotechnol Bioeng 43:1153–1163
Jackson RB, Mooney HA, Schulze ED (1997) A global budget for fine root biomass, surface area, and nutrient contents. Proc Natl Acad Sci USA 94:7362–7366
Kelly JM, Graves WR, Aiello A (2000) Nitrate uptake kinetics for rooted cuttings of Acer rubrum L. Plant Soil 221:221–230
Kelly JM, Kelly JK (2001) Phosphorus and potassium uptake kinetics in red maple seedlings. For Sci 47:397–402
Kelly JM, Scarbrough JD, Mays PA (2001) Hardwood seedling root and nutrient parameters for a model of nutrient uptake. J Environ Qual 30:427–439
Kielland K (1994) Amino acid absorption by arctic plants: implications for plant nutrition and nitrogen cycling. Ecology 75:2373–2383
Law BE, Ryan MG, Anthoni PM (1999) Seasonal and annual respiration of a ponderosa pine ecosystem. Glob Change Biol 5:169–182
Leadley PW, Reynolds JF, Chapin FS III (1997) A model of nitrogen uptake by Eriophorum vaginatum roots in the field: ecological implications. Ecol Monogr 67:1–22
Patterson M (1998) Commensuration and theories of value in ecological economics. Ecol Econ 25:105–125
Poorter H, Remkes C, Lambers H (1990) Carbon and nitrogen economy of 24 wild species differing in relative growth rate. Plant Physiol 94:621–627
Scheible WR, Lauerer M, Schulze ED, Caboche M, Stitt M (1997) Accumulation of nitrate in the shoot acts as a signal to regulate shoot–root allocation in tobacco. Plant J 11:671–691
Scheurwater I, Cornelissen C, Dictus F, Welschen R, Lambers H (1998) Why do fast- and slow-growing grass species differ so little in their rate of root respiration, considering the large differences in rate of growth and ion uptake? Plant Cell Environ 21:995–1005
Schimel JP, Bennett J (2004) Nitrogen mineralization: challenges of a changing paradigm. Ecology 85:591–602
Skogsmyr I, Fagerstrom T (1992) The cost of anti-herbivory defence: an evaluation of some ecological and physiological factors. Oikos 64:451–457
Tinker PB, Nye PH (2000) Solute movement in the rhizosphere. Oxford University Press, Oxford, 444 p
Tjoelker MG, Craine JM, Wedin D, Reich PB, Tilman D (2005) Linking leaf and root trait syndromes among 39 grassland and savannah species. New Phytol 167:493–508
Van Rees KCJ, Comerford NB, Rao PSC (1990) Defining soil buffer power: implications for ion diffusion and nutrient uptake modeling. Soil Sci Soc Am J 54:1505–1507
Venterea RT, Rolston DE (2000) Mechanistic modeling of nitrite accumulation and nitrogen oxide gas emissions during nitrification. J Environ Qual 29:1741–1751
Volder A, Smart DR, Bloom AJ, Eissenstat DM (2005) Rapid decline in nitrate uptake and respiration with age in fine lateral roots of grape: implications for root efficiency and competitive effectiveness. New Phytol 165:493–501
Wedin DA, Tilman D (1990) Species effects on nitrogen cycling: a test with perennial grasses. Oecologia 84:433–441
Yanai RD, Fahey TJ, Miller SL (1995) Efficiency of nutrient acquisition by fine roots and mycorrhizae. In: Smith WK, Hickley TM (eds) Resource physiology of conifers. Academic Press, San Diego, pp 75–103
Acknowledgements
Trevor Wennblom and the staff of the Dartmouth Research Computing Facility provided invaluable help with writing the code and running the simulations. JMC was supported by the Andrew Mellon Foundation and an NSF International Research Fellowship.
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Craine, J.M. Competition for Nutrients and Optimal Root Allocation. Plant Soil 285, 171–185 (2006). https://doi.org/10.1007/s11104-006-9002-x
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DOI: https://doi.org/10.1007/s11104-006-9002-x