Switchgrass Biomass Quality as Affected by Nitrogen Rate, Harvest Time, and Storage

Abstract

Core Ideas Switchgrass, being an efficient perennial biofuel crop, can be used as an alternative to fossil fuels and help in the sustainability of energy. Thus, it is important that we understand the effect of storing switchgrass for extended periods of time. Storing switchgrass for an extended period may have an impact on quality and yield. Storing switchgrass in bales or as a standing crop in the field are two storage methods assessed in this study. The purpose of this study was to assess the changes in switchgrass (Panicum virgatum L.) biomass quality as affected by N rate, harvest time, and storage. This research was conducted near Bristol, SD, in 2010 and 2011. Treatments included three N rates (0, 56, and 112 kg N ha−1) applied annually and each N rate replicated four times. After a killing frost, all of the plots were harvested and baled in large round bales in October 2010 and November 2011. An area of about 30 m2 from each plot was left unharvested to represent storage of standing switchgrass over the winter and to determine dry matter yields. Switchgrass was analyzed for hemicellulose, cellulose, lignin, mineral elements, N, and C. In the first season, storage of the fall harvested switchgrass bales numerically increased the concentrations of hemicellulose, lignin, and N. In the second season, they increased significantly. Mineral elements significantly increased in both sampling seasons. Delaying harvest until spring decreased lignin, N, and mineral elements concentration, and increased cellulose and hemicellulose concentrations, but also reduced biomass yield. Results from this study suggest that delaying the switchgrass harvest until spring increased the overall feedstock quality for ethanol production, but yield reductions must be considered to determine the overall economic impact of a delayed harvest.

Poultry Litter and Inorganic Fertilization: Effects on Biomass Yield, Metal and Nutrient Concentration of Three Mixed-Season Perennial Forages

“…across various studies [17][18][19]. Similar results have also been seen in switchgrass (Panicum virgatum L.) [20]. More nutrient concentrations were also observed in switchgrass and perennial legumes like alfalfa (Medicago sativa L.) grown on poultry-litter-amended soils [21,22].…”

Long‐term influence of phosphorus fertilization on organic carbon and nitrogen in soil aggregates under no‐till corn–wheat–soybean rotations

“…© 2020 The Authors. Agronomy Journal © 2020 American Society of Agronomy matter requires the availability of several nutrients (Ibrahim et al, 2017). The C/N/P/S ratio of humus suggested by Lal (2004) and Himes (1998) is 10,000:833:200:143, which indicates that N, P, and S contents in soil are tightly linked to C present in soil organic matter.…”

Harvest and nitrogen effects on bioenergy feedstock quality of grass‐legume mixtures on Conservation Reserve Program grasslands

“…Increased N was consistently reported to increase the overall yield and biomass-N concentrations (Arundale et al, 2015;Gurezky et al, 2011;Ibrahim et al, 2017;Lemus et al, 2008;Mulkey et al, 2008;Murozuka et al, 2014;Vogel et al, 2002). The additional N supply, however, has been reported to have positive (Allison et al, 2012;Arundale et al, 2015;Hong et al, 2014;Lemus et al, 2008;Nazli & Tansi, 2019;Waramit et al, 2011), negative (Hodgson et al, 2010), or no effects (Lee et al, 2007;Ibrahim et al, 2017;Seepaul et al, 2014) on cellulose and lignin concentrations in the monoculture production studies. In the mixture systems, biomass compositions were influenced by the confounding factors of N treatments and species transitions.…”

“…Nitrogen effects on biomass compositions, however, are substantially influenced by environmental variations (weather and soils) and species (Allison et al, 2012;Emery et al, 2020;Heggenstaller et al, 2009;Hong et al, 2014;Waramit et al, 2011). Increased N was consistently reported to increase the overall yield and biomass-N concentrations (Arundale et al, 2015;Gurezky et al, 2011;Ibrahim et al, 2017;Lemus et al, 2008;Mulkey et al, 2008;Murozuka et al, 2014;Vogel et al, 2002). The additional N supply, however, has been reported to have positive (Allison et al, 2012;Arundale et al, 2015;Hong et al, 2014;Lemus et al, 2008;Nazli & Tansi, 2019;Waramit et al, 2011), negative (Hodgson et al, 2010), or no effects (Lee et al, 2007;Ibrahim et al, 2017;Seepaul et al, 2014) on cellulose and lignin concentrations in the monoculture production studies.…”