Nitrogen, phosphorus, and potassium utilization in the plant-soil system: an analytical model

Journal Article · Thu Jan 01 00:00:00 EST 1976 · Soil Sci. Soc. Am. J.; (United States)

DOI:https://doi.org/10.2136/sssaj1976.03615995004000050029x· OSTI ID:7116094

Smith, O L

An intermediate-resolution analytical model of nitrogen, phosphorus, and potassium utilization in the plant-soil system was developed and tested. Starting from specified natural or artificial sources in the soil, element transport to root absorption surfaces was modeled in terms of diffusion, mass flow, and soil buffering mechanisms. Element uptake was described by carrier theory formalism, and assimilation was based on four premises about the roles of N, P, K, and photosynthate in cell chemistry. There were three main objectives of the model. The first was to predict the first-order interactive growth response of particular plant species to any combination of these macronutrients supplied in the soil medium. Species parameters required by the model include root absorption rate and certain cell chemistry reaction rates. The second objective was to make the model sufficiently general to describe a broad range of species. It was built upon common denominator principles of physiology condensed from available experimental data on corn (Zea mays L.), bean (Phaseolus vulgaris), pine (Pinus elliottii Var. elliottii), etc. In this generic sense it is a measure of what plants have in common. The third objective was to use the model to test several well-known theories of plant growth. The model was validated against reported experiments on ryegrass (Lolium perenne L.), oat (Avena sativa), a legume (Stylosanthes humilis), and rutabaga (Brassica napobrassica, Mill.), in which dry matter yield was measured as a function of factorial application of N, P, and K to the soil. The model shows that much of the deficient, optimal, toxic, and interactive response of plants to N, P, and K can be explained in terms of strong linear response of cell chemistry to low nutrient concentrations and inhibition by N, P, and K at high nutrient concentrations.

• Research Organization: Oak Ridge National Lab., TN
• OSTI ID: 7116094
• Journal Information: Soil Sci. Soc. Am. J.; (United States), Vol. 40:5
• Country of Publication: United States
• Language: English

Related Subjects

60 APPLIED LIFE SCIENCES
NITROGEN
SOIL CHEMISTRY
PHOSPHORUS
PLANTS
NUTRIENTS
POTASSIUM
ABSORPTION
FERTILIZERS
GRASS
GROWTH
MAIZE
MATHEMATICAL MODELS
OATS
PHASEOLUS
PINES
REACTION KINETICS
ROOTS
SOILS
ALKALI METALS
BIOMASS
CEREALS
CHEMISTRY
CONIFERS
CRYOGENIC FLUIDS
ELEMENTS
ENERGY SOURCES
FLUIDS
GRAMINEAE
KINETICS
LEGUMINOSAE
METALS
NONMETALS
RENEWABLE ENERGY SOURCES
TREES
553000* - Agriculture & Food Technology