Phosphorus diffusion to barley (Hordeum vulgare) roots as influenced by moisture and phosphorus content of soils

Abstract

Rapid diffusion in the soil macropores and a much slower one in the micropores have been shown. Effects of soil moisture- and P-content on the effective diffusion coefficients are also obtained. The soil volumes in which P moves towards the roots and the amount of P moving by rapid and slow diffusion were estimated by the effective diffusion coefficients, root growth dynamics and soil P-fractions, obtained in different moisture and nutrient states.

In the soil with low P-buffering power the rapid diffusion process determines P-transport, whereas in more buffered soil the depletion volume is much smaller and the slow diffusion process is significant in P-supply.