Solid and Liquid Phases of Anaerobic Digestate for Sustainable Use of Agricultural Soil

Abstract

Given the growth in the number of biogas power plants and the increase in the generation of waste from energy production, it is relevant to study the sustainable nature of this waste. Digestate is a product of the anaerobic digestion process, and is a valuable bio-fertilizer containing organic matter and nutrients necessary for agricultural plants’ growth. The study showed that different rates of liquid and solid phases of anaerobic digestate influenced the contents of carbon and nitrogen in genetically young soil in alluvial deposits—Fluvisol. The application of solid digestate (SD) considerably increased soil organic carbon content (SOC) in the 0–10 cm soil layer; however, SOC did not reach the 20–30 cm layer. Liquid digestate (LD) significantly increased SOC in the deeper layers. The levels of mineral nitrogen (Nmin) and water extractable organic carbon (WEOC) increased in the 0–10 cm soil layer soon after fertilization with LD and SD. The mobile components of the soil (Nmin and WEOC) were characterized by high variability during the growing season. Within the 2-month period, their concentrations decreased drastically and were close to those of unfertilized soil. The research indicates that anaerobic digestate had a greater effect on mobile forms of carbon and nitrogen in the soil than on their total amounts.

The Impact of Profile Genesis and Land Use of Histosol on Its Organic Substance Stability and Humic Acid Quality at the Molecular Level

“…Total soil nitrogen (N) and the total phosphorus (P) contents were determined using a spectrophotometric measure procedure at a wavelength of 655 nm and 430 nm after mineralization with sulphuric acid (H 2 SO 4 ). The content of total potassium (K) was determined using an atomic absorption meter AAnalyst 200 (Perken Elmer, Waltham, MA, USA) [46]. Soil organic carbon content (SOC) was determined by a photometric procedure at the wavelength of 590 nm after wet combustion, according to Nikitin (1999) [47].…”

Effect of organic pest control products on Arbuscular Mycorrhizal colonization in Bulgarian rose plantations: A two-year field study

“…The content of available potassium ranged between 16.60 mg 100 g -1 and 17.27 mg 100 g -1 . The content of SOC was measured according to the Nikitin-modified Tyurin method using the spectrophotometric procedure at the wavelength of 590 nm (Slepetiene et al, 2023). For the study period the values of SOC varied between 14.9 mg g -1 and 15.7 mg g -1 .…”

Nature‐based strategies to regenerate the functioning and biodiversity of vineyards

“…However, most studies are concerned with the digestion of grape pomace, but few refer to wine lees or grape stalks (Chiappero et al, 2023;El Achkar et al, 2017;Da Ros et al, 2016). Anaerobic digestates could be applied to agricultural soils and might be used in both their solid and liquid phases, depending on their characteristics (Slepetiene et al, 2023).…”

“…However, most studies are concerned with the digestion of grape pomace, but few refer to wine lees or grape stalks (Chiappero et al, 2023; El Achkar et al, 2017; Da Ros et al, 2016). Anaerobic digestates could be applied to agricultural soils and might be used in both their solid and liquid phases, depending on their characteristics (Slepetiene et al, 2023). Vermicomposting (organic matter transformation by earthworms) is another viable biotechnology for the treatment of wine organic wastes, as demonstrated by several studies (Gómez‐Brandón et al, 2021, 2023; Karapantzou et al, 2023; Paradelo et al, 2011).…”