All of the following apply to estuaries EXCEPT: There provide very valuable breeding grounds for commercially important fish and shellfish. There is no salinity in estuarine ecosystems due to large supply of fresh water from a river. Plants and algae that grow here have high tolerance for changing environmental conditions like salinity and light penetration. These coastal ecosystems provide a barrier against the ocean during storms.

There is no salinity in estuarine ecosystems due to large supply of fresh water from a river.

Explanation:

An estuary is a semi-closed body of water where fresh water and sea water meet and merge. Even though they are not a habitat to diverse species, they are very valuable breeding grounds and are one of the most productive environments. It is true that plants and algae that grow there have high tolerance for changing environmental conditions like salinity and light penetration because fluctuations happen from time to time because of the influence of the tides. And because of the partially enclosed nature of estuaries, there is provision for a barrier against the ocean during storms.

But despite the supply of fresh water, there is actually salinity in estuarine ecosystems which also varies depending on the concentration of sea water to fresh water.