Why does increasing soil salinity have adverse effects on plant cells?

Increasing soil salinity will have an adverse effect on plant cells. The movement of water from the soil to the plant is known as osmosis. There needs to be some salt in the soil for osmosis to take place. If the salt content in the soil is too high compared to the salt levels in the plant cells, the plant cannot absorb water and dies of thirst even though there is lots of water. The same occurs in the reverse. 

Of the cold they can survive in the cold

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