ISSN:
1573-5036
Source:
Springer Online Journal Archives 1860-2000
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Summary Phosphorus supply factors (capacity, kinetic, intensity, and diffusivity) and plant growth were the approaches used to assess P supply of flooded rice soils. Increases in the capacity, intensity, and kinetic factors, as measured by E-value, solution P concentration, and soil P release rate to a distilled water ‘sink’ respectively, were unpronouced and infrequent upon water-saturation of ten soils. However, increases in the diffusitivity factor, as measured by 32P diffusion coefficients, were at least ten-fold as soil moisture increased. The greatest increases in P diffusion occurred as soil moisture increased beyond one-third bar. Using a P fertilized soil or P treated powdered cellulose as the P source and a minus P nutrient solution to nourish a split root system with water and nutrients, data were obtained which suggested that P uptake and rice-shoot growth (indicators of P availability) increased with increasing moisture level. Phosphorus uptake and rice-shoot growth were greatst when the soil or P treated cellulose were water-saturated. These data indicate that increased soil P availability upon flooding can be attributed to an increase in the diffusivity factor.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00011700
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