Taste bud receptors if not stimulated are normally polarized. With the presence of the food, chemicals from the food bind with the cell protein which depolarized the cell membrane receptor. Depolarization will lead into the propagation of electric impulse. This will lead into the creation of sensory impulse. The larger number of the chemicals in the food will lead into a stronger impulse.
Salinity refers to an increase in the dissolved salt content of a body of water. Salinity has great impacts on the type of organisms that live inside the water. In the question given above, the salinity occurs as a result of non natural influence; since most of the organisms living inside the water before probably have specific optimal salinity range, if the salinity exceed the range they can cope with, they will probably migrate away from the water, those that refuse to migrate will probably die out and new species which can cope with the salinity level will emerge.
Related to living organisms
the biotics requlating of the environment is a key to global change
A biodiversity
Hope this helps