Abstract
Production of biofuels from corn or other food crops is considered unsustainable in the long term since it creates artificial shortages in food supply, increases in food price, and subsequent socioeconomic and environmental concerns. Second-generation biofuels, however, have shown promise, with improvement in technologies for converting cellulosic feedstocks into liquid transportation fuels. The development of biomass feedstock production systems and advanced biofuel refineries in floodplains and marginal lands can generate up to 45 t of biomass and 14,000 l of advanced biofuel per hectare per year, achieving considerable offset in dependence on fossil fuel. Promising biomass species for floodplains include short-rotation trees such as poplar and willow, perennial grasses such as Miscanthus and switchgrass, and annuals such as high-biomass sorghum. However, river floodplains are often susceptible to flooding and drought events, partly due to the impact of climate change on hydrological cycles and human interventions such as the construction of dams and levees. In the USA, floodplain biofuel production systems could generate up to 30% of renewable biofuels by 2022 and provide additional benefits such as carbon sequestration, GHG reduction and ecosystem sustainability. However, successful implementation will depend on the social adaptability and economic viability of such systems.
Acknowledgements
The authors would like to thank the anonymous referees for helpful comments on an earlier version of the manuscript. Discussions with S Flick, P Nelson, B Hood, S Sachdev and M Gold were helpful in elaborating on the floodplains for biomass production concept.
Financial & competing interests disclosure
The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.
No writing assistance was utilized in the production of this manuscript.