Location: Soil Dynamics ResearchTitle: Producing sorghum cellulosic feedstock for advanced biofuels production and its impact on soil physical properties ) Author
Submitted to: Sustainable Feedstocks for Advanced Biofuels
Publication Type: Abstract Only
Publication Acceptance Date: 8/12/2010
Publication Date: 1/15/2011
Citation: Rocateli, A.C., Raper, R.L., Arriaga, F.J., Balkcom, K.S., Bransby, D.I., Ortiz, B.V. 2011. Producing sorghum cellulosic feedstock for advanced biofuels production and its impact on soil physical properties [abstract]. Sustainable Feedstocks for Advanced Biofuels. Available at: http://www.swcs.org/documents/filelibrary/roadmap/SFAB_Program_and_Abstract_Book__FIN_8607CF9B02A16.pdf Interpretive Summary:
Technical Abstract: According Energy Policy Act of 2005, the U.S. must produce 21 billion gallons of advanced biofuels in 2022. Cellulosic material is considered a renewable and environmental improved alternative source for energy production. Sorghum (Sorghum bicolor L.) is considered a high cellulosic biomass productive plant with low Nitrogen inputs. Thus, sorghum can be produced in rotation with other common cash crops. However, soil physical impacts caused by removing cellulosic biomass on soils must not be ignored. Therefore, the objectives of this study were to evaluate sorghum and corn cellulosic biomass production (quantity/quality), and to monitor soil physical properties, such as bulk density (Bd) and cone index (CI) when producing and removing sorghum/corm biomass. The types of sorghum evaluated were: grain sorghum - NK300 (GS), high biomass forage sorghum – SS 506 (FS), and photoperiod sensitive forage sorghum - 1990 (PS). These 3 different varieties and a forage corn (Zea mays L.) - Pioneer 31G65 were grown in 2008 and 2009 under irrigated and non-irrigated treatments, and under two different tillage systems: conventional and conservation tillage. Results after two years of cropping showed that irrigation and conventional tillage resulted in high aboveground biomass production (ADM). PS was considered the best tested variety in order to produce ADM which produced 26.04 and 30.13 Mg/ha at 18 and 24 weeks after planting. Biomas quality parameters, such as holocellulose, lignin and ash content showed low differences among varieties, and they were considered minor. Additionally, soil consolidation was observed after two years of cropping. Bd values increased at all depths, but those values were always lower than threshold for soil compaction. PS showed significant lower Bd than corn in superficial layers (0.05 - 0.20 m). Conventional plots had higher Bd in some evaluated layers. Cone Index (CI) values also showed improved soil conditions at in-row positions for conservation plots, with restrictive layers being found at depths of 0.15 m for conventional plots. Therefore, conservation tillage and photoperiod sensitive sorghum (1990) - PS were considered the best alternatives to produce cellulosic feedstock biomass and to diminish soil physical impacts.