Question

Acid rain is produced when rain mixes with gases such as sulphur dioxide. This will eventually result in

• A. Lowering of pH and changes of temperature in ponds
• B. Raising of pH in ponds, encouraging growth of if microorganisms
• C. Lowering of pH in ponds, limiting survival of aquatic organisms
• D. Raising of pH in ponds, limiting development of organisms

Answer 1

The correct option is C Lowering of pH in ponds, limiting survival of aquatic organisms

The ecological effects of acid rain are most clearly seen in the aquatic environments, such as streams, lakes, etc. Acid rain flows into streams, lakes and marshes after falling on forests, fields, building and roads. Acid rain water primarily decreases the pH of water sources from normal range (6 to 8 pH) Lakes and streams become acidic (i.e., pH values goes down), when water itself and its surrounding soil cannot buffer the acid rain water to neutralize it. In areas where buffering capacity is low, acid rain releases aluminium from soils into lakes and streams, aluminium is highly toxic to many species of aquatic organisms leading to their mortality. Therefore, limiting the survival of aquatic animals. So, the correct answer is 'Lowering of pH in ponds, limiting survival of aquatic organisms'.