Supply of Nutrients to Plant Roots

For References: text, page 282

There are three main processes by which nutrients are supplied to plant roots:

1. Mass flow of soil solution to the plant root as a result of water uptake.

2. Diffusion of ions from solid phases or regions of high concentration towards the plant root as concentrations become depleted due to nutrient absorption.

3. Root interception as a result of the root growing and occupying more space.

The table below shows the relative amounts of several nutrients supplied to corn roots by the three processes.

Nutrient	Total Uptake	Root Interception	Mass-Flow	Diffusion
Ca	23	66	175	.
Mg	28	16	105	.
K	135	4	35	96
P	39	1	2	36
Mn	0.23	0.10	0.05	0.08
Zn	0.23	0.10	0.53	.
Cu	0.16	0.01	0.35	.
B	0.07	0.02	0.70	.
Fe	0.80	0.10	0.53	0.17

From: Soil Testing and Plant Analysis. 1973. Editors, Leo M. Walsh and James D. Beaton. Soil Science Society of America. Madison, Wisconsin.

Home