Effects of harvest frequency and biosolids application on switchgrass yield, feedstock quality, and theoretical ethanol yield

Abstract

Sustainable development of a bioenergy industry will require low-cost, high-yielding biomass feedstock of desirable quality. Switchgrass (Panicum virgatum L.) is one of the primary feedstock candidates in North America, but the potential to grow this biomass crop using fertility from biosolids has not been fully explored. The objective of this study was to examine the effects of harvest frequency and biosolids application on switchgrass in Virginia, USA. 'Cave-in-Rock' switchgrass from well-established plots was cut once (November) or twice (July and November) per year between 2010 and 2012. Class A biosolids were applied once at rates of 0, 153, 306, and 459 kg N ha À1 in May 2010. Biomass yield, neutral and acid detergent fiber, cellulose, hemicellulose, lignin, and ash were determined. Theoretical ethanol potential (TEP, l ethanol Mg À1 biomass) and yield (TEY, l ethanol ha À1) were calculated based on cellulose and hemicellulose concentrations. Cutting twice per season produced greater biomass yields than one cutting (11.7 vs. 9.8 Mg ha À1 ) in 2011, but no differences were observed in other years. Cutting once produced feedstock with greater TEP (478 vs. 438 l Mg À1 ), but no differences in TEY between cutting frequencies. Biosolids applied at 153, 306, and 459 kg N ha À1 increased biomass yields by 25%, 37%, and 46%, and TEY by 25%, 34%, and 42%, respectively. Biosolids had inconsistent effects on feedstock quality and TEP. A single, end-of-season harvest likely will be preferred based on apparent advantages in feedstock quality. Biosolids can serve as an effective alternative to N fertilizer in switchgrass-to-energy systems.

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

“…In addition, optimal quality varies depending on the conversion technique used to generate energy (Liu et al, 2015). Generally, we found no significant differences in the concentrations of fiber constituents among N rates within each sampling date (Table 1) (Table 1).…”

Biosolids and biochar application effects on bahiagrass herbage accumulation and nutritive value

“…A significant body of literature has demonstrated numerous agronomic benefits associated with land application of biosolids to pastures (Adjei & Rechcigl, 2002; Barbarick, Doxtader, Redente, & Brobst, 2004; Sigua et al., 2005). Land application of biosolids to perennial pasture provides essential plant nutrients and organic matter and serve as a liming agent to acid pasture soils (Adjei & Rechcigl, 2002; Antille et al., 2017; Avery et al., 2018; Liu, Fike, Galbraith, & Fike, 2015a, 2015b; Sigua et al., 2005; Tiffany et al., 2001a, 2001b). Research demonstrated that when applied at equivalent N rates, biosolids resulted in either similar or greater forage production as inorganic fertilizer (Adjei & Rechcigl, 2002).…”

Effects of crop type and harvest on nest survival and productivity of dickcissels in semi-natural grasslands

“…Additionally, these mixed species plantings provide resources important for breeding birds including potential nest sites and arthropods for nestling sustenance (Simpson, 1949;MacArthur and MacArthur, 1961;Wiens, 1974;Rotenberry, 1985;McCoy et al, 2001). Biofuel production also requires annual or semi-annual harvests, with a main cutting traditionally during fall or winter months to maximize total biomass, and a potential secondary cutting for forage or biomass during the summer (Vogel et al, 2002;Fike et al, 2006;Liu et al, 2015). As such, the timing of these additional harvest events can be detrimental to avian species if they occur during the breeding season (Roth et al, 2005) because they destroy active nests, remove vegetative cover, and reduce food availability (Bollinger et al, 1990;Kershner and Bollinger, 1996;Warren and Anderson, 2005;Perlut et al, 2006).…”