Location: Natural Resource Management ResearchTitle: Biomass composition of perennial grasses for biofuel production in North Dakota, USA Author
Submitted to: Biofuels
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/18/2010
Publication Date: 9/1/2011
Publication URL: http://handle.nal.usda.gov/10113/53935
Citation: Xue, Q., Nyren, P.E., Wang, G., Eriksmoen, E., Bradbury, G., Halvorson, M., Aberle, E., Nichols, K.A., Liebig, M.A. 2011. Biomass composition of perennial grasses for biofuel production in North Dakota, USA. Biofuels. 2(5):515-528. doi: 10.4155/bfs.11.123 Interpretive Summary: Using biomass as feedstocks in bioenergy production has the potential to replace fossil fuels as well as corn grain which may be better use as human and livestock feed. The northern Great Plains provides a vast number of acres for perennial biomass production, particularly in highly erodible and non-productive areas which would have a low impact on food production. To achieve the most success in biomass conversion, feedstocks most suited to the region in terms of biomass quantity and quality need to be identified. High quality feedstocks are typically lower in ash and lignin content and higher in hemicellulose and cellulose. In this study, 10 biomass treatments of perennial grasses or mixtures were grown at five locations (one location had plots under dryland and irrigated conditions) across a precipitation gradient from eastern to western North Dakota. Eight sub-plots of each of the 10 biomass crops were planted at each location with half harvested annually and half harvested biennially, resulting in four replicate treatment plots. In the second year of the study or the first production year, biomass samples were collected and analyzed for biomass yield, neutral detergent fiber, acid detergent fiber, acid detergent lignin, hemicellulose, cellulose, and ash content. Biomass yield varied largely across environments with mean yields ranging from 1.4 to 11 Mg/ha under 318 mm (12.5 inches) or 431 mm (17 inches), respectively. Under dry environments, cool season grasses such as tall wheatgrass and intermediate wheatgrass were dominant over warm season species such as switchgrass and big bluestem. The biomass chemical composition was strongly affected by environment, plant species, and their interactions. Under dry conditions, neutral detergent fiber, acid detergent lignin, and hemicellulose contents were higher while cellulose content was lower. Tall and intermediate wheatgrass generally had higher neutral detergent fiber, acid detergent fiber, and cellulose but lower ash content than switchgrass and wildrye, while switchgrass and mixtures had higher hemicellulose content. Tall wheatgrass and Sunburst switchgrass had the lowest acid detergent lignin content across environments. Tall and intermediate wheatgrass and switchgrass had higher yields and the optimal chemical compositions to be most suitable for biomass feedstock production across North Dakota.
Technical Abstract: Successful development of biofuels from biomass feedstocks depends on high yields and acceptable quality. We investigated the chemical composition of ten perennial grasses and mixtures across environments in North Dakota, USA. The contents of neutral detergent fiber, acid detergent fiber, acid detergent lignin, hemicellulose, cellulose and ash were determined. Results: Biomass chemical composition was affected by environment and species/mixtures, and their interaction. Biomass under drier conditions had higher neutral detergent fiber, acid detergent lignin and hemicellulose contents but lower cellulose contents. Tall and intermediate wheatgrass had higher neutral detergent fiber, acid detergent fiber and cellulose but lower ash contents than the other species and mixtures. Switchgrass and mixtures had higher hemicellulose. Tall wheatgrass and Sunburst switchgrass had the lowest acid detergent lignin content as compared with other species. Biomass with higher yield had higher cellulose content but lower ash content. Conclusion: Combined with higher yields, tall and intermediate wheatgrass and switchgrass had the optimal chemical compositions for biomass feedstocks production.