Improved Organic Fertilisers Made from Combinations of Compost, Biochar, and Anaerobic Digestate: Evaluation of Maize Growth and Soil Metrics

Noemí Ortiz-Liébana (), Andrea Crespo-Barreiro, Ismael Mazuecos-Aguilera and Fernando González-Andrés
Additional contact information
Noemí Ortiz-Liébana: Chemical, Environmental and Bioprocess Engineering Group, Institute of Environment, Natural Resources and Biodiversity, University of León, Av. Portugal, 41, 24009 León, Spain
Andrea Crespo-Barreiro: Chemical, Environmental and Bioprocess Engineering Group, Institute of Environment, Natural Resources and Biodiversity, University of León, Av. Portugal, 41, 24009 León, Spain
Ismael Mazuecos-Aguilera: Chemical, Environmental and Bioprocess Engineering Group, Institute of Environment, Natural Resources and Biodiversity, University of León, Av. Portugal, 41, 24009 León, Spain
Fernando González-Andrés: Chemical, Environmental and Bioprocess Engineering Group, Institute of Environment, Natural Resources and Biodiversity, University of León, Av. Portugal, 41, 24009 León, Spain

Agriculture, 2023, vol. 13, issue 8, 1-19

Abstract: Treated bio-residues can be used as biostimulants in crops within the circular economy approach to reduce the use of traditional fertilisers. In this work, we optimised the combination rates for three types of treated bio-residues (compost, biochar, and anaerobic digestate (AD)) in two microcosm trials, one with a combination of compost and biochar and other with biochar and AD. The crop used was maize, and the variables analysed were plant growth, and soil chemical and biological properties. The combination of bio-residues improved plant growth and soil biological activity to a greater extent than one product alone; that is, compost and biochar performed better than compost alone and biochar, and AD performed better than biochar alone. However, while the concentration in the plant biomass of several essential nutrients for crops increased in the treatments with compost and biochar, and with biochar and AD, compared to the untreated controls, the nitrogen concentration was reduced. This was due to the competition for nitrogen between the plant and the soil microbiome, whose activity was activated. Due to the importance of nitrogen in plant growth, the increase in biomass production could be explained not only by the higher availability of other nutrients but also by the plant-growth-promoting activity exerted by the more active soil microbiome. Further research should focus on validating this hypothesis and unravelling the mechanisms involved. From the environmental site, the presence of biochar in the mixtures of organic residues reduced the soil nitrogen at risk of lixiviation and sequestered carbon, which partially compensated for the increased CO 2 emissions because labile forms of carbon were present in the remaining organic residues.

Keywords: compost; biochar; anaerobic digestate; organic fertiliser; greenhouse trial; maize; soil biological activity; bio-residues (search for similar items in EconPapers)
JEL-codes: Q1 Q10 Q11 Q12 Q13 Q14 Q15 Q16 Q17 Q18 (search for similar items in EconPapers)
Date: 2023
References: View references in EconPapers View complete reference list from CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/2077-0472/13/8/1557/pdf (application/pdf)
https://www.mdpi.com/2077-0472/13/8/1557/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jagris:v:13:y:2023:i:8:p:1557-:d:1210369

Access Statistics for this article

Agriculture is currently edited by Ms. Leda Xuan

More articles in Agriculture from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().