• Plants thrive in very specific environments.plants image by Melissa Schalke from Fotolia.com
  
  Terrestrial, or land, plants are only able to process relatively low levels of salt that are common in their native environments and to which they are specifically adapted. When exposed to high levels of salt, such as that found in saltwater, land plants can suffer different adverse and damaging effects.
  
  

Salt Flooding

• When land plants are exposed to saltwater caused by flooding from close-by saltwater bodies, the saltwater can damage or destroy plant roots and eventually kill the plant. If the saltwater flooding is chronic, then these dangers amplify. Flooding of saltwater also damages a plant's ability to respire, which is when organisms release energy from glucose and make it available in the form of ATP for chemical, osmotic and other use. This is because soil generally has small air pockets through which plant roots absorb the oxygen necessary to respire. When an area is flooded with saltwater, plants can no longer find the oxygen they need to absorb and respire.
  
  

Internal Salt

• For many land plants, salt becomes poisonous in high concentrations, such as those found in saltwater, and can damage plant tissue over time. If a plant regularly comes in contact with saltwater, the salt will begin to leach into the plant. This can cause many internal problems for the plant, including damaging crucial cell processes, interfering with important enzymes, oxidation and other negative effects.
  
  

Salt Adaptation

• Some land plants, mangroves for example, have evolved to resist certain damages incurred from saltwater. These adaptations can involve special glands that secrete excess salt through plant leaves, or salt storage in leaves which is then disposed of when the plant naturally sheds its leaves. Other plants have evolved special salt-proof roots that prevent salt from entering into the plant in the first place.
  
  

Osmosis

• Osmosis is the process through which plant root cells absorb water. This water goes from an area with a low concentration of dissolved minerals through cells until it reaches an area of highly concentrated dissolved minerals. In normal circumstances, the dissolved minerals in plant cells keep water flowing continuously through the plant's roots. However, when the water in the soil becomes too salty, the osmosis process is negatively affected. The high concentration of dissolved salt in water can slow the rate at which the water flows into the plant's roots and can even end up sucking water out of the roots. If the water becomes salty enough, it can eventually kill the plant by dehydrating it.