"pavlov noticed that dogs began salivating at the mere sight of the person who regularly brought food to them. for the dogs, the sight of this person had become a(n): "

affects the water bodies: excessive use of fertilizers causes eutrophication. the fertilizers which are used on plants affect the quality of land on which it is used, further causing erosion of soil. the fertilizers used on plants contain harmful chemical fumes which affect the environment.