The HTF directs efforts to reduce nutrient pollution in which river basin and associated gulf hypoxic zone?

• A. Mississippi/Atchafalaya River Basin and Gulf of Mexico hypoxic zone
• B. Ohio River Basin and Baltic Sea
• C. Columbia River Basin and Puget Sound
• D. Missouri River Basin and Gulf of St. Lawrence

Answer: (A)

Excess nutrients from fertilizer runoff enter large river basins and fuel algal blooms; when those blooms die and decompose, oxygen is consumed and dead zones can form in nearby waters. The Mississippi/Atchafalaya River Basin drains a vast agricultural area, delivering nitrogen and phosphorus to the Gulf of Mexico. The resulting Gulf of Mexico hypoxic zone is the well-known example of nutrient-driven low-oxygen conditions linked to that basin. That connection is why the HTF focuses on reducing nutrient pollution there. Other basins point to nutrient problems in different regions (for example, Europe’s Baltic Sea, the Pacific Northwest’s Puget Sound, or the Gulf of St. Lawrence) and aren’t the specific Gulf hypoxia tied to the Mississippi drainage.