Hostname: page-component-cd9895bd7-jn8rn Total loading time: 0 Render date: 2024-12-26T18:55:28.388Z Has data issue: false hasContentIssue false

Competition for plant nutrients in soil; a theoretical approach

Published online by Cambridge University Press:  27 March 2009

J. P. Baldwin
Affiliation:
Department of Agricultural Science, University of Oxford

Summary

A mathematical model of whole plant growth in soil is presented. Particular emphasis is given to those factors which relate to the absorption of nutrients and water by the root system. There are two basic premises; that a plant is made up of two pools, structural material and precursors to structural material, and that structural material is produced by a reaction between a given ratio of precursors. The precursors are soluble carbohydrate and unbound nitrogen, probably nitrate. Increase in leaf area and root length is a consequence of absorbed nitrogen combining with photosynthate.

The absorbing power and the distribution throughout the soil of the roots is controlled, through feedback mechanisms, by the ratio of the precursors, within the plant. The description of plant growth is interfaced with a model of one-dimensional flow of water and solutes in soil, and gives a model for investigating plant growth, or competition between root systems of more than one plant. The results of a number of simulations are presented. A sensitivity coefficient is defined to compare the effect of various properties on overall growth. Its value is calculated for 11 plant properties. It is some measure of the competitive advantage conferred on the plant by a change in the value of each property. The results of the competition experiments are given as replacement diagrams.

The model has weaknesses. Because it is explicit, it defines in precise detail the experiments which would support the hypotheses, or suggest modifications to them. As a holistic analysis, it brings together ideas from different disciplines into one comprehensible framework.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1976

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Aspinall, D. (1960). An analysis of competition between barley and white persicaria. II. Annals of Applied Biology 48, 637–54.CrossRefGoogle Scholar
Baldwin, J. P. & Nye, P. H. (1974). Uptake of solutes by multiple root systems from soil. IV. Plant and Soil 40, 703–6.CrossRefGoogle Scholar
Baldwin, J. P., Nye, P. H. & Tinker, P. B. H. (1973). Uptake of solutes by multiple root systems from soil. III. Plant and Soil 38, 621–35.CrossRefGoogle Scholar
Brouwer, R. (1966). Root growth of grasses and cereals. In The Growth of Cereals and Grasses (ed. Milthorpe, F. L. and Ivins, J. D.). London: Butterworth.Google Scholar
Donald, C. M. (1958). The interaction of competition for light and nutrients. Australian Journal of Agricultural Research 9, 421–35.CrossRefGoogle Scholar
Drew, M. C. & Saker, L. R. (1975). Nutrient supply and growth of the seminal root system in barley. II. Journal of Experimental Botany 26, 7990.CrossRefGoogle Scholar
Drew, M. C, Saker, L. R. & Ashley, T. W. (1973). Nutrient supply and the growth of the seminal root system in barley. Journal of Experimental Botany 24, 1189–202.CrossRefGoogle Scholar
Epstein, E. & Hagen, C. E. (1952). A kinetic study of the absorption of alkali cations by barley roots. Plant Physiology 27, 457–73.CrossRefGoogle ScholarPubMed
Gardner, W. R. (1960). Dynamic aspects of water availability to plants. Soil Science 89, 6373.CrossRefGoogle Scholar
Gerwitz, A. & Page, E. R. (1974). An empirical mathematical model to describe plant root systems. Journal of Applied Ecology 11, 773–80.CrossRefGoogle Scholar
Hackett, C. & Rose, D. A. (1972). A model of the extension and branching of a seminal root of barley, and its use in studying relations between root dimensions. Australian Journal of Biological Science 25, 681–90.CrossRefGoogle Scholar
Hanks, R. J. & Bowers, S. A. (1962). Numerical solutions of the moisture flow equation for infiltration into layered soils. Soil Science Society of American Proceedings 26, 530–4.CrossRefGoogle Scholar
Honert, Van Den T. H. (1948). Water transport in plants as a catenary process. Discussions of Faraday Society 3, 146–53.CrossRefGoogle Scholar
Hunt, R. & Burnet, J. A. (1973). The effects of light intensity and external potassium level on root/shoot ratio and rates of potassium uptake in perennial rye grass. Annals of Botany 37, 519–37.CrossRefGoogle Scholar
May, L. H., Chapman, F. M. & Aspinall, D. (1965). Quantitative studies of root development. Australian Journal of Biological Science 18, 2535.CrossRefGoogle Scholar
Milthorpe, F. (1961). Mechanism of biological competition. Society of Experimental Biology 15, 330.Google Scholar
Milthorpe, F. (1968). In Water Deficits and Plant Growth (ed. Kozlowski, T. T.). New York and London: Academic Press.Google Scholar
Milthorpe, F. & Moorby, J. (1974). An Introduction to Crop Physiology. Cambridge University Press.Google Scholar
Molz, F. J. & Remson, J. (1970). Extraction term models of soil moisture use by transpiring plants. Water Resources Research 6, 1346–56.CrossRefGoogle Scholar
Nimah, M. N. & Hanks, R. J. (1973). Model for estimating soil water, plant and atmospheric inter-relations. Soil Science Society of American Proceedings 37, 522–32.CrossRefGoogle Scholar
Nye, P. H. & Tinker, P. B. (1969). The concept of a root demand coefficient. Journal of Applied Ecology 6, 293300.CrossRefGoogle Scholar
Pearsall, W. H. (1927). Growth studies. VI. On the relative sizes of growing plant organs. Annals of Botany, London 163, 549–56.CrossRefGoogle Scholar
Rawlins, S. L.Gardner, W. R. & Dalton, F. N. (1968). In situ measurement of soil and plant leaf water potential. Soil Science Society of American Proceedings 32, 468–70. 23–2CrossRefGoogle Scholar
Reicosky, D. C, Millington, R. J., White, A. & Peters, D. B. (1972). Patterns of water uptake and root distribution of soybeans in the presence of a water table. Agronomy Journal 64, 292–7.CrossRefGoogle Scholar
Richtmyer, R. D. (1957). Difference Methods for Initial Value Problems. New York: Interscience.Google Scholar
Rowse, H. (1974). The effect of irrigation on the length weight and diameter of lettuce roots. Plant and Soil (in the Press).CrossRefGoogle Scholar
Scaife, A. (1974). Computer simulation of nitrogen uptake and growth. Proceedings of the 7th International Colloquium on plant analysis and fertilizer problems (Hanover) 74, 413–26.Google Scholar
Scaife, M. A. & Smith, R. (1973). The phosphorus requirement of lettuce. Journal of Agricultural Science, Cambridge 80, 353–61.CrossRefGoogle Scholar
Sutcliffe, J. F. (1962). Mineral Salts Absorption in Plants. Oxford: Pergamon.CrossRefGoogle Scholar
Taylor, H. M. & Klepper, B. (1973). Rooting density and water extraction patterns for corn. Agronomy Journal 65, 965–8.CrossRefGoogle Scholar
Taylor, H. M. & Klepper, B. (1975). Water uptake by cotton root systems. Soil Science (in the Press).CrossRefGoogle Scholar
Thornley, J. H. M. (1972). A balanced quantitative model for root: shoot ratios in vegetative plants. Annals of Botany 36, 431–41.CrossRefGoogle Scholar
Tinklin, R. & Weatherley, P. E. (1966). On the relationship between transpiration rate and leaf water potential. New Phytologist 65, 509–17.CrossRefGoogle Scholar
Troughton, A. (1957). The underground organs of herbage grasses. Commonwealth Bureau of Pasture Field Crop Bulletin 44.Google Scholar
Van Der Ploeg, R. R. & Benegke, P. (1975). Unsteady, unsaturated, n-dimensional moisture flow in soil. Soil Science Society of America Proceedings 38, 881–5.CrossRefGoogle Scholar
Wit, C. T. De (1960). On competition. Verslagen van Landbouwkundige Onderzoehingen.Google Scholar