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ARS Home » Southeast Area » Fayetteville, Arkansas » Poultry Production and Product Safety Research » Research » Publications at this Location » Publication #400345
Research Project: Developing Best Management Practices for Poultry Litter to Improve Agronomic Value and Reduce Air, Soil and Water Pollution

Location: Poultry Production and Product Safety Research

Title: Short term effects of composted digestate on soil health and crop yield: Implication for sustainable waste management in the bioenergy sector

Author
item GURMESSA, BIYENSA - Polytechnic University Of Marche
item COCCO, STEFANIA - Polytechnic University Of Marche
item CARDELLI, VALERIA - Polytechnic University Of Marche
item ILARI, ALESSIO - Polytechnic University Of Marche
item SERRANI, DOMINIQUE - Polytechnic University Of Marche
item Ashworth, Amanda
item FORNASIER, FLAVIO - Crea
item DEL GATTO, ANDREA - Crea
item PEDRETTI, ESTER - Polytechnic University Of Marche
item CORTI, GIUSEPPE - Polytechnic University Of Marche

Submitted to: Science of the Total Environment
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/17/2023
Publication Date: 1/1/2024
Citation: Gurmessa, B., Cocco, S., Cardelli, V., Ilari, A., Serrani, D., Ashworth, A.J., Fornasier, F., Del Gatto, A., Pedretti, E.F., Corti, G. 2024. Short term effects of composted digestate on soil health and crop yield: Implication for sustainable waste management in the bioenergy sector. Science of the Total Environment. 906. Article 167208. https://doi.org/10.1016/j.scitotenv.2023.167208.
DOI: https://doi.org/10.1016/j.scitotenv.2023.167208

Interpretive Summary: The bioenergy revolution in Europe has resulted in of millions of tons of solid digestate annually, which is often directly used as fertilizer in many member States. Agronomic benefits of digestate have been well recognized, however, its demand by farmers could be unsatisfactory mainly due to the transportation cost from source to field and other environmental challenges linked to direct land application. Environmental concerns are often associated with emissions, salinity, phytotoxicity, and trace element loading. Hence, there is a need for post-digestate treatment to mitigate these issues. Composting is one such treatment could yield a more stable product with a more favorable fertilizer composition compared to non-composted organic amendments. Researchers therefore set out to understand the role of compost-derived from digestate as fertilizer and its effects on soil quality and sunflower oil yield and overall soil health. This study found that composted digestate can substitute inorganic fertilizer for sunflower production, as it supplies sufficient nutrients for even better oil yields.

Technical Abstract: Digestate has been widely used as fertilizer because of its environmentally safety relative to raw material. However, there is a declining demand because of its low nutrient content and cost of application, and consequently, onsite treatments (e.g., composting) have been recommended. The current study thus aimed at understanding the role of compost-derived from digestate as fertilizer, as a substitute for inorganic fertilizer and their effects on soil quality and sunflower (Helianthus annuus L.) achene and oil yields. Treatments applied were digestate, composted digestate, co-composted digestate with its original feedstock materials (maize silage, food processing byproduct, poultry litter, poultry litter plus maize silage), and inorganic N. Soil Management Assessment Framework (SMAF) was used to identify key soil quality indicators and estimate soil quality index (SQI). Further, Partial Least Square Path Model (PLS-PM) was used to predict sunflower agronomic yield. Results showed that composted digestate can be a potential substitute for inorganic fertilizer and digestate in terms of agronomic yield although life cycle assessment study may be suggested to further understand the relative environmental benefits. Soil C/N ratio, two ecoenzymatic activities (Leucine aminopeptidase, Phosphodiesterase), and exchangeable Ca and Na were identified as key soil quality indicators. SQI was affected by crop stage, which increased at pre-flowering and harvest periods, irrespective of treatments, suggesting possible interaction with time and crop driven soil functions. PLS-PM predictive potential was high (GoF = 0.7), and it revealed weak link between SQI and agronomic yield (oil and achene), despite specific parameters such as available P and total N contents showing positive and negative impacts, respectively, on agronomic yield. In conclusion, suggesting the importance of finding a balance between N and available P application rates when using organic amendments for fertilizer.