Ideas in this flowchart

• Cation exchange keeps nutrient cations available to plants while limiting their loss from soil.
• It prevents positively charged nutrients from being rapidly washed away by water.
• It keeps the nutrients available for later plant uptake.
• Root-mediated exchange occurs at soil surfaces.
• Plant roots release hydrogen ions.
• Plant roots also release hydrogen ions derived from carbonic acid.
• These hydrogen ions exchange with nutrient cations on soil surfaces.
• The released nutrients return to the soil solution.
• The nutrients can move toward plant roots.