Yield and quality analyses of bioenergy crops grown on a regulatory brownfield

Agriculture faces unique challenges as increasing world population places unprecedented demands on food, feed, and energy resources. In an effort to become more efficient and sustainable, marginal land, including regulatory brownfields prohibited for food consumption purposes could be utilized for bioenergy crop production. In 2006–2008, we evaluated soybean (Glycine Max (L.) Merr.), canola (Brassica napus L. var. napus), sunflower (Helianthus annuus L.), and switchgrass (Panicum virgatum L.) to determine crop suitability for bioenergy production on a regulatory brownfield site. Sites selected for the study included a remediated brownfield site in Rose Township, Oakland County, and a historically cropped agricultural site at East Lansing, Ingham County, serving as the control. Comparisons of biofuel quality components were conducted. The total oil yield of oilseed crops was not significantly different (p < 0.05) between locations. Concentrations of palmitic (C16:0), stearic (C18:0), oleic (C18:1), linoleic (C18:2), and linolenic (C18:3) fatty acids differed by location, yet oleic acid concentrations, optimal for quality biodiesel production, were not significantly different across all oilseed crops. Total crystalline cellulose levels from switchgrass were higher at the agricultural land site compared to the brownfield site in 2007 yielding 16% more crystalline cellulose; but there were no differences between locations in 2008. Detectable levels of PCB's were found in soils at the brownfield site; however, transfer to grain or biomass was not detected. Results suggest that brownfield sites have the potential to produce feedstock of suitable quality for conversion to liquid transportation fuels.

► Brownfield bioenergy crop yield and quality were acceptable.
► No traces of contaminant were found in the resulting bioenergy crop feedstock.
► The potential exists for similar brownfield sites to be options for bioenergy production.
► Brownfield sites should be assessed on a case-by-case basis.