Saltwater usually harms plants and most plants cannot survive in these conditions, but some can. One of the main reasons why most plants do not thrive on saltwater is that it can cause growth problems. Plants that can survive in saltwater use the salt to their benefit.

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Algae manage to thrive in saltwater.

Water and Plants

Most plants cannot survive with too much water, especially too much saltwater. Many land plants need air for their roots to survive. The air pockets in the soil help roots absorb the oxygen needed for their survival. If their roots absorb too much water, saltwater or not, it blocks nutrients from entering their system.

Saltwater Dangers on Plants

Saltwater is a danger to plants because of the chemical composition. The salt causes the plant to lose the water in its leaves. The plant will eventually dry out and die without an ample supply of water.

Plants and Salt

Most plants need a small amount of salt, as do humans, to survive. If a land-based plant absorbs too much salt, it penetrates the tissues and prevents the plant from carrying on normal activities. Excessive salt content can stunt a plant's growth.

Halophytes

Plants called halophytes have evolved to live in saltwater. These plants are equipped with membrane barriers that prevent salt from entering the root systems. Other plants absorb the salt and secrete it out of glands designed to do so. Many of these plants have deep roots that help protect them against saltwater.

Algae

Algae are one of the most commonly known saltwater plants. This plant is a simple organism that uses photosynthesis to make energy like many other plants. Algae are equipped with systems that help get rid of the salt in the water, which helps them survive.

Scientists and Saltwater Irrigation

Scientists are researching methods that would help farmers use saltwater to their advantage and grow crops. This would free up freshwater resources for other means such as drinking. Their research is made up of diluted saltwater irrigation methods and altering plants to allow them to survive salt exposure.

Considerations

It is best to keep land-based plants away from exposure to saltwater since many of them are not equipped to survive salt exposure. Fresh water is best for these land-based plants.