Abstract
AIM: This study aimed to simulate deactivation of E. coli in soils amended with cattlemanure after burning, anaerobic digestion, composting or without treatment.
METHOD AND RESULTS: The Weibull survival function was used to describe deactivation of E. coli. Parameters for each treatment were determined using E. coli measurements from manure-amended soils and evaluated against measurements at different application rates. A statistically significant correlation and high coincidence between the simulated and measured values was obtained. The simulations revealed that although anaerobic digestion or burning of cattle manure effectively reduced the E. coli loads to background levels, burning retained very little nitrogen, so the ash residue was ineffective as an organic
fertiliser. Anaerobic digestion was most effective at reducing E. coli levels while retaining a high proportion of N in the bioslurry residue, but the persistence of E. coli was higher than in compost.
CONCLUSION: The results from this study suggest that the safest method for production of
organic fertiliser would involve anaerobic digestion to reduce E. coli followed by composting to reduce its persistence.
SIGNIFICANCE AND IMPACT OF STUDY: These findings are important for the development of safe methods to supply nitrogen to food crops from E. coli contaminated manures.
METHOD AND RESULTS: The Weibull survival function was used to describe deactivation of E. coli. Parameters for each treatment were determined using E. coli measurements from manure-amended soils and evaluated against measurements at different application rates. A statistically significant correlation and high coincidence between the simulated and measured values was obtained. The simulations revealed that although anaerobic digestion or burning of cattle manure effectively reduced the E. coli loads to background levels, burning retained very little nitrogen, so the ash residue was ineffective as an organic
fertiliser. Anaerobic digestion was most effective at reducing E. coli levels while retaining a high proportion of N in the bioslurry residue, but the persistence of E. coli was higher than in compost.
CONCLUSION: The results from this study suggest that the safest method for production of
organic fertiliser would involve anaerobic digestion to reduce E. coli followed by composting to reduce its persistence.
SIGNIFICANCE AND IMPACT OF STUDY: These findings are important for the development of safe methods to supply nitrogen to food crops from E. coli contaminated manures.
| Original language | English |
|---|---|
| Article number | lxad098 |
| Number of pages | 7 |
| Journal | Journal of Applied Microbiology |
| Volume | 134 |
| Issue number | 6 |
| Early online date | 8 May 2023 |
| DOIs | |
| Publication status | Published - 2 Jun 2023 |
Bibliographical note
Open Access via the OUP AgreementACKNOWLEDGEMENTS
We are grateful to the School of Biological sciences, University of Aberdeen and Federation of European Microbiology Societies for providing travel and research funding for VAC. Inputs from JS were supported by the Global Challenges Research Fund “South Asian Nitrogen” Hub [grant number NE/S009019/1] and “Reducing land degradation and carbon loss from Ethiopia's soils to strengthen livelihoods and resilience (RALENTIR) [grant number ES/T003073/1].
Data Availability Statement
The data underlying this article will be shared on reasonable request to the corresponding author.Keywords
- cattle manure
- fertilizer
- e. coli
- weibull survival function
- deactivation
- burn
- nitrogen
Access to Document
- Chukwu_etal_JAM_Modelling_deactivation_Escherichia_VOR
Copyright The Author(s) 2023. Published by Oxford University Press on behalf of Applied Microbiology International. This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial License (https://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited.