Effects of 5 years of digestate application on biomass production and quality of cocksfoot (Dactylis glomerata L.)

Abstract

Anaerobic digestion of biomass produces biogas for combustion and also provides a residual digestate. Although sometimes regarded as a waste product, the nutrient‐rich chemical composition of digestate makes it a potential organic fertilizer for agriculture. The goal of this study was to evaluate the effectiveness of digestate as a fertilizer on the biomass yield and chemical composition of cocksfoot (Dactylis glomerata L.). In a 5‐year small‐plot field experiment digestate fertilization treatments supplying 90, 180, 270, 360 and 450 kg N ha−1 were compared with untreated plots and plots fertilized with 180 kg N ha−1 of mineral N fertilizer. Swards fertilized with digestate produced higher biomass yield compared with the control. The same rate of nitrogen fertilizer (180 kg N ha−1) supplied as digestate and from mineral fertilizers gave similar results on biomass yield. Herbage in swards fertilized with digestate contained less nitrogen, but the C:N ratio was much more suitable for biogas production. Digestate fertilization resulted in higher concentrations of cellulose and hemicellulose in biomass and lower contents of the inhibitors of anaerobic digestion—sulphur, calcium, magnesium and phosphorus—compared with those of swards receiving mineral fertilizers.

Efecto de bacterias PGPB, composta y digestato en el rendimiento de materia seca de pasto ovillo

“…Con respecto a los resultados obtenidos con el digestato, estos coinciden con lo expuesto por Rancane et al (2015); Walsh et al (2012), quienes observaron un incremento en el rendimiento del forraje con la adición de digestato. Por su parte Tilvikiené et al (2018) evaluaron el rendimiento de biomasa en pasto Ovillo fertilizado con diferentes concentraciones de digestatos durante cinco años consecutivos y notaron que la fertilización con este abono causa grandes concentraciones de componentes estructurales (celulosas y hemicelulosa) en la biomasa, lo que repercute en un mayor rendimiento del forraje. -Aguilar et al (2018), advirtieron que el riego con digestato (60%) después de cada corte favorece el incremento del rendimiento de forraje de Lolium perenne, obteniendo más de 150% de rendimiento en comparación del testigo (suelo solo).…”

Changes in the area of permanent grassland and its implications for the provision of bioenergy: Slovakia as a case study

“…() compared three scenarios of biomethane production from Irish grassland and reported that biomethane from grasslands had a good energy balance. An additional potential benefit of using grass as a feedstock in AD is that the digestate by‐product is a nutrient‐rich product that can be returned to the system to support future herbage production (Tilvikien≐ et al., ). Nevertheless, because of a risk of NH 3 emissions during spreading and storage, the use of digestate requires special attention and logistics management particularly in areas with high concentrations of AD plants (Rehl & Műller, ).…”

“…Harvested forage from grassland for AD, especially where it is surplus to the current requirements for livestock, is increasingly being regarded as an alternative land‐use option (Wachendorf & Soussana, ). Several studies have been conducted to quantify the bioenergy potential of herbage from both semi‐natural and sown grasslands (Florine, Moore, Fales, White, & Burras, ; Herrmann, Prochnow, Heiermann, & Idler, ; Khalsa, Fricke, Weigelt, & Wachendorf, ; Melts, Heinsoo, & Ivask, ; Tilvikien≐, Šlepetien≐, & Kadžiulien≐, ; Van Meerbeek et al., ). Grasslands that are currently surplus to agricultural requirements have potential for biogas production under management that also allows the maintenance of ecosystem services including biodiversity (Heinsoo, Melts, Sammul, & Holm, ; Prochnow et al., ; Robertson, Doran, Loomis, & Robertson, ; Rösch, Skarka, Raab, & Stelzer, ).…”

“…Biodegradation of lignocellulosic feedstock is difficult to achieve resulting in lower biogas yield (Melts & Heinsoo, ). The commonly sown species of agricultural grassland such as perennial ryegrass ( Lolium perenne ), Italian ryegrass ( Lolium multiflorum ) timothy ( Phleum pratense ), cocksfoot ( Dactylis glomerata ) and red clover ( Trifolium pratense ) can, however, offer high bioenergy potential, particularly under management that includes use of nitrogen fertilization and optimum harvest dates (King, McEniry, Richardson, & O'Kiely, ; Tilvikien≐ et al., ).…”

“…In the last 20 years, the potential of grassland for bioenergy has received increased attention (Hadders & Olsson, 1997;Kryzeviciene, 2005). Harvested forage from grassland for AD, especially where it is surplus to the current requirements for livestock, is increasingly being regarded as an alternative land-use option (Wachendorf & Soussana, 2012 e, 2018;Van Meerbeek et al, 2015). Grasslands that are currently surplus to agricultural requirements have potential for biogas production under management that also allows the maintenance of ecosystem services including biodiversity (Heinsoo, Melts, Sammul, & Holm, 2010;Prochnow et al, 2009;Robertson, Doran, Loomis, & Robertson, 2011;R€ osch, Skarka, Raab, & Stelzer, 2009).…”