Salinity — harmful to your plants?

How salinity affects plants

Here are some negative impacts of using saline irrigation on plants:

• Osmotic Stress: Osmosis is the process that allows the plant roots to drink soil’s water. It is the movement of solvent molecules through a semi-permeable membrane from a region of lower solute concentration to a region of higher solute concentration, in the direction that tends to equalize the solute concentrations on the two sides. To put it simply, when you have a glass of water separated by a membrane that allows only water to pass through, the water will move from the region where there is less salt to the region where there is more in order to equalize the salt concentration from both sides.

In the plant, it is that process that allows the roots to drink water from the soil, because the concentration in salts is higher in the plant than in the soil’s water. 

This is where increasing salinity becomes a problem. If the soil’s water gets more saline, it will allow less water to enter the root or even prevent it. This is what we call osmotic stress.

• Toxicity: Excessive salts, especially sodium and chloride, can lead to leaf burn, disrupt nutrient uptake from the soil, and damage cell membranes, reducing overall plant health.

• Oxidative Stress: High salinity induces the plant to create certain molecules in response to it that harm the plant, called oxidative stress. 

• Soil Degradation: High sodium deteriorates soil structure, causes salt crusts on the soil surface and reduces microbial activity, harming soil health.