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Agriculture must expand production for a growing population while simultaneously reducing its environmental impacts. These goals need not be in tension with one another. Here we outline a vision for improving both the productivity and environmental performance of agriculture in the US Corn Belt. Mean annual precipitation has increased throughout the region over the past 50 years, consistent with climate models that attribute it to a warming troposphere. Stream gauge data indicate that higher precipitation has been matched or exceeded by higher stream flows, contributing to flooding, soil loss, and excessive nutrient flux to the Gulf of Mexico. We propose increasing landscape hydrologic storage through construction of ponds and restoration of wetlands to retain water for supplemental irrigation while also reducing flood risks. Primary productivity is proportional to transpiration, and analysis shows that in the US Midwest both can be sustainably increased with supplemental irrigation. This will reduce interannual yield variability by limiting losses due to transient drought, while facilitating adoption of cropping system modifications, such as inclusion of companion crops and winter cover crops, that “perennialize” the landscape to take advantage of the full potential growing season. When implemented in concert, these practices would reduce the riverine nitrogen export that is a primary cause of hypoxia in the Gulf of Mexico. Erosive sediment losses would also be reduced through the combination of enhanced hydrologic storage and increased vegetative cover. Successful implementation would require watershed-scale coordination among producers and landowners. An obvious mechanism to encourage this is governmental farm policy.
