Which process describes nutrients leaching from land into a body of water, causing algal blooms and deoxygenation?

Which process describes nutrients leaching from land into a body of water, causing algal blooms and deoxygenation?

• A. Pollution
• B. Eutrophication
• C. Runoff
• D. Leaching

Answer: (B)

Nutrient enrichment of a water body triggers rapid algae growth and then oxygen depletion. When nutrients like nitrates and phosphates leach from soil into a lake or river, they act like fertilizer for algae, causing blooms. As these algae die and decompose, bacteria use up dissolved oxygen, leading to deoxygenation that can harm aquatic life. This sequence is eutrophication—the buildup of nutrients in water that drives algal blooms and low oxygen. Leaching describes the movement of nutrients from land into water, while runoff is another pathway bringing nutrients to waterways; pollution is a broad term for harmful contaminants.

Nutrient enrichment of a water body triggers rapid algae growth and then oxygen depletion. When nutrients like nitrates and phosphates leach from soil into a lake or river, they act like fertilizer for algae, causing blooms. As these algae die and decompose, bacteria use up dissolved oxygen, leading to deoxygenation that can harm aquatic life. This sequence is eutrophication—the buildup of nutrients in water that drives algal blooms and low oxygen. Leaching describes the movement of nutrients from land into water, while runoff is another pathway bringing nutrients to waterways; pollution is a broad term for harmful contaminants.