Potential water quality changes due to corn expansion in the Upper Mississippi River Basin

摘要: While biofuels may yield renewable fuel benefits, there could be downsides in terms of water quality and other environmental stressors, particularly if corn is relied upon exclusively as the feedstock. The consequences increased production will depend importantly on where (and how) additional grown, which, turn, depends characteristics land its associated profitability. Previous work has rules thumb for allocating to acreage based historical use or heuristics. Here, we advance our understanding these phenomena by describing a modeling system that links an economics-driven model with watershed-based Upper Mississippi River Basin (UMRB). This used assess changes due acreage, which higher relative prices. We focus six scenarios realistic pairs soybean prices correspond scale decreasing price ratio. These price-driven provide estimates effects current biofuel policies have UMRB. Our analysis can help evaluate costs implementation strategies mandates new energy bill. amounts total N P delivered outlet UMRB (located at Grafton, Illinois, USA) rise becomes more intensive region. results indicate 14.4% watershed intensification most economically profitable locations would result 5.4% increase nitrogen loads 4.1% phosphorus Grafton. aggressive scenario, driven high but not out reach crop prices, about 57% corresponding 18.5% 12% P. are somewhat conservative increases nutrients, compared those previous studies, likely cultivated cropland already heavily fertilized.