Summary
Most current models of the water uptake by plant roots from the soil profile solve the equation for flow of water in unsaturated soils. The boundary condition at the root-soil interface is represented, whether explicitly or implicitly by some kind of root distribution function. Such models have sufficient number of parameters so that they can be fitted to data reasonably well. Most water uptake patterns, when normalized with respect to root zone depth and plant extractable water reveal, remarkable similarities regardless of soil texture, plant species, or root distribution. This similarity is not predictable with current models. A model based upon non-linear behavior of the root membranes and described by a distributed sink moving downward through the soil profile adequately represents the uptake process. The shape of the sink function is not critical and only two parameters, a root depth parameter, and an extractable water parameter are needed.
Keywords
Water Uptake Soil Profile Extractable Water Unsaturated Soil Root DistributionPreview
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References
- Ahuja LR, Nielsen DR (1990) Field soil-water relations. In: Stewart BA, Nielsen DR (eds) Irrigation of agricultural crops. Am Soc Agron, Madison, p 144Google Scholar
- Aylmore LA, Hamza G, Hamza M (1990) Water and solute movement to plant roots. Trans 14 Int Cong Soil Sci, Kyoto II: 124Google Scholar
- Black TA, Gardner WR, Tanner CB (1970) Water storage and drainage under a row crop on a sandy soil. Agron J 62:48Google Scholar
- Black TA, Gardner WR, Thurtell GW (1969) The prediction of evaporation, drainage, and soil water storage for a bare soil. SSSS Proc 33:655Google Scholar
- Carslaw HS, Jaeger JC (1959) Heat conduction in soils. Oxford University Press, Oxford, 510 ppGoogle Scholar
- Dalton FN, Raats PAC, Gardner WR (1975) Simultaneous uptake of water and solutes by plant roots. SSSA J 67:334Google Scholar
- Gardner HR, Gardner WR (1969) Relation of water application to evaporation and storage of soil water SSSA J 33:192Google Scholar
- Gardner WR (1960) Dynamic aspects of water availability to plants. Soil Sci 89:63Google Scholar
- Gardner WR, Ehlig CF (1962a) Some observations on the movement of water to plant roots. Agron J 54:453Google Scholar
- Gardner WR, Ehlig CF (1962b) Impedance to water movement in soil and plant. Science 138:522Google Scholar
- Gardner WR, Ehlig CF (1963) The influence of soil water on transpiration by plants. J Geophys Res 68:5719Google Scholar
- Gardner WR (1964) Relation of root distribution to water uptake and availability. Agron J 56:41Google Scholar
- Gardner WR (1983) Soil properties and efficient water use: An overview. In: Taylor HM, Jordan WR, Sinclair TR (eds) Limitations to efficient water use in crop production. Am Soc Agron, Madison, p 45Google Scholar
- Herkelrath WN, Miller EE, Gardner WR (1977) Water uptake by plants I. Divided root experiments. SSSA J 41:1033Google Scholar
- Herkelrath WN, Miller EE, Gardner WR (1977) Water uptake by plants. II. The root contact model. SSSA J 41:1039Google Scholar
- Klepper B (1990) Root growth and water uptake. In: Stewart BA, Nielsen DR (eds) Irrigation of agricultural crops. Am Soc Agron, Madison, p 282Google Scholar
- Merrill SD, Rawlins SL (1979) Distribution and growth of sorghum roots in response to irrigation frequency. Agron J 71:738Google Scholar
- Molz FJ (1971) Interaction of water uptake and root distribution. Agron J 63:608Google Scholar
- Ogata G, Richards LA, Gardner WR (1960) Transpiration of alfalfa determined from soil water content changes. Soil Sci 89:179Google Scholar
- So HB, Aylmore LAG, Quirk JP (1976) The resistance of intact maize roots to water flow. SSSA J 40:222Google Scholar