Interest in commercially viable cellulosic biofuel production has greatly increased due to concerns regarding the sustainability of petroleum fuels. These biofuels can help fulfill escalating demands for liquid fuels and mitigate the environmental impacts of petroleum-derived fuels. Two key factors in their successful large- scale production are pretreatment (in biological conversion processes) and a consistent supply of feedstock. While research into solving the technical issues is ongoing, much less attention has been paid to solving supply chain challenges such as low bulk density of cellulosic biomass, compositional variability and seasonality of the feedstock. Currently large biorefineries face many logistical problems because they are centralized facilities in which all units of the conversion process are present in a single location. These logistical problems can be addressed using a system of distributed processing networks called Regional/Local Biomass Processing Depots (RBPDs, LBPDs or depots). These depots are strategically distributed facilities that procure, pre-process /pre-treat and densify biomass into stable intermediate products that are compatible with existing bulk commodity logistical systems. On the agricultural production side, an array of feedstocks such as corn stover, switchgrass, miscanthus, native prairie grasses etc. are being evaluated as potential raw materials for cellulosic biofuel production. Additionally, management practices such as the use of marginal lands, no-till and double-cropping, riparian buffers, when incorporated in the feedstock module of the biofuels supply chain, may enhance overall system sustainability. However, thorough assessments are required in real landscape settings on regional levels before these feedstocks can be cultivated and sustainable practices can be implemented. Likewise biofuel production should be maximized and negative environmental impacts should be minimized in growing these new feedstocks.This research has two primary objectives: to propose designs of sustainable optimized cellulosic feedstock landscapes for biofuel production and to conduct integrated systems-wide life cycle analyses of these optimized landscapes combined with distributed processing and associated auxiliary processes (such as transport operations). It also aims to address pertinent current issues in the bioenergy production sector such as: avoiding indirect land use change impacts (iLUC) and the "feed vs. fuel" controversy, maximizing ecosystem services and improving the quality of water bodies. The watershed-scale optimized & rearranged landscape design (WORLD) model was created to estimate land allocations for different cellulosic feedstocks at biorefinery scale while paying attention to the aforementioned issues. In summary, this research answers several key questions in the biofuel production process regarding the advantages of distributed processing systems, the technical potential of landscapes and maximizing the benefits of these landscapes plus processing systems for environmental, economic and social incentives. The WORLD model and integrated LCAs can be used as decision making tools by growers, industries or policy makers.
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