Recent U.S. Energy Policy such as the Renewable Fuels Standard has been created to reduce our dependence on fossil fuels and mitigate global climate change. The GLBRC Bioenergy Cropping Experiment, established in 2008 at UW-Madison and MSU, contains annual cropping systems (corn, soybeans, canola) and perennial cropping systems (switchgrass, miscanthus, a native grass mix, old field, poplar, a prairie grass mix). Field inputs, gas emissions, and yields have been tracked since establishment. This field data was used to perform a life cycle assessment on these cropping systems with a focus on the global warming potential (GWP). The results of the LCA showed that the continuous corn cropping systems had the highest GWP per hectare per year at both study locations as expected. The perennial systems generally had a negative GWP per hectare per year due to limited inputs and gas emissions from those systems. The material inputs that contributed most to GWP were synthetic nitrogen fertilizers. Nitrous oxide emissions had the greatest effect on the GWP of each cropping system of all of the gas emissions considered. The second chapter of this thesis research focused on a successful and cost effective establishment method for switchgrass. Switchgrass is an herbaceous perennial grass capable of producing large amounts of biomass. The biomass can be converted to cellulosic ethanol. Stand establishment to maximum biomass potential required several years. A field experiment was conducted to identify if a double cropping management system was possible for switchgrass establishment. The results of the experiment showed that August seeded switchgrass could not be successfully established following a wheat crop. June seeded switchgrass after a rye crop and fallow (control treatment) were successfully established. No significant differences in stand establishment or yields were seen between these two treatments.
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