Designing Biomass Cropping Systems for Sustainable Bioenergy Production.

Many annual and perennial grasses are being evaluated for their potential as dedicated bioenergy crops. We established a dedicated bioenergy cropping systems study at Arkansas State University to investigate the sustainability of various bioenergy crops and various sources of nitrogen with regards to soil and water quality and sustainability. Our objective for this part of the study was to determine nitrogen uptake patterns and nitrogen use efficiency for high biomass sorghum fertilized with fertilizer urea, municipal biosolids, and poultry litter. We also monitored soil carbon and nitrogen as well as microbial activity indicators from these same treatments. Biomass yields in the first year of the study showed no significant differences among nutrient sources, but were greater than the control. However, plant height and nitrogen uptake were influenced by nutrient source.  Research outcomes from this project will provide new knowledge in support of the sustainability of various dedicated energy crops and their management.  Proven sustainable options for growing dedicated energy crops in the southern region will allow growers to use best management practices in managing their farms.