Which is a well-known dead zone example caused by nutrient runoff from the Mississippi River?

Which is a well-known dead zone example caused by nutrient runoff from the Mississippi River?

• A. Bay of Bengal
• B. Baltic Sea
• C. Gulf of Mexico
• D. Great Barrier Reef

Answer: (D)

When excess nutrients enter a water body, they fuel rapid algal growth. When the algae die, decomposers consume large amounts of dissolved oxygen, especially in waters with layered circulation, leading to hypoxic or “dead” zones where most aquatic life cannot survive. The Mississippi River drains a huge agricultural region, carrying nitrogen and phosphorus into the Gulf of Mexico. There, the nutrients trigger blooms and, after they decompose, bottom waters become starved of oxygen for extended periods. This creates one of the most well-known hypoxic zones in the world, tied directly to that river’s nutrient runoff. The other locations have their own environmental issues, but they’re not the classic Mississippi-driven dead zone.

When excess nutrients enter a water body, they fuel rapid algal growth. When the algae die, decomposers consume large amounts of dissolved oxygen, especially in waters with layered circulation, leading to hypoxic or “dead” zones where most aquatic life cannot survive. The Mississippi River drains a huge agricultural region, carrying nitrogen and phosphorus into the Gulf of Mexico. There, the nutrients trigger blooms and, after they decompose, bottom waters become starved of oxygen for extended periods. This creates one of the most well-known hypoxic zones in the world, tied directly to that river’s nutrient runoff.

The other locations have their own environmental issues, but they’re not the classic Mississippi-driven dead zone.