Accumulation

The soil solution contains the ions of the important plant mineral nutrients that are taken up by plant roots. Even if the concentration may be low, the anions and cations that are freely dissolved in the soil solution are the most easily assimilated by the roots. There are three ways in which these nutrients reach near roots:
(1) Ions diffusing through the soil solution
(2) The passively charged ions carried by the bulk flow of water into the roots and
(3) Roots’ development is extended toward the dissolved ions. Ion uptake is characterized by three principles in both higher and lower plants.