Cost-effective targeting of conservation investments to reduce the northern Gulf of Mexico hypoxic zone

摘要: A seasonally occurring summer hypoxic (low oxygen) zone in the northern Gulf of Mexico is second largest world. Reductions nutrients from agricultural cropland its watershed are needed to reduce size national policy goal 5,000 km2 (as a 5-y running average) set by Task Force’s Action Plan. We develop an integrated assessment model linking water quality effects conservation investment decisions on more than 550 subwatersheds that deliver into with model. use this identify most cost-effective target for investments. consider targeting location (which treat) and extent undertake (how much within subwatershed treat). process models simulate dynamics investments nutrient delivery evolutionary algorithm solve optimization problem. Model results suggest coverage, Plan can be achieved at cost $2.7 billion annually. large cost-hypoxia tradeoffs developed, ranging baseline nontargeted adoption aggressive all (estimated less 3,000 $5.6 annually).