Evaluation of biochar soil amendments in reducing soil and water pollution from pathogens in poultry manure
Notice bibliographique
Résumé
This project addresses concerns from the Canadian public about the quality of water in regions where many agricultural operations are located. Fecal coliforms are endemic in poultry and are difficult to eradicate from production facilities. Poultry manure is a reservoir of Campylobacter jejuni, Escherichia coli (including O157:H7) and Salmonella spp. Biochar, the charcoal produced from pyrolysis of biomass, is gaining global recognition due to its unique properties when applied as a soil amendment. Biochar could play an important role in controlling the mobility of pathogens in soil and water environment. Its half-life is estimated to be hundreds of years so it is expected that its role in reducing agricultural pollution could be very long-lasting, and hence very cost-effective.In this study we investigated the effectiveness of biochar in preventing the leaching of fecal coliforms into surface water. The target organisms in this study were Escherichia coli (E .coli) and total coliform. E. coli is widely recognized as the indicator organism for presence of fecal coliform and total coliforms to determine disinfection rate. The study was divided into two components, namely laboratory study and field study.In laboratory study, the effectiveness of three different types of biochar (variation based on production temperature, time and raw material) in adsorption and desorption of E. coli was studied. In adsorption test, a comparative analysis was carried out to understand the differences between biochar, soil amended biochar (soil to biochar ratio of 99:1) and un-amended soil in the removal of E. coli. The statistical analysis showed the adsorption of E. coli was significantly higher in the soil amended biochar treatment. The soil amended biochar and the un-amended soil treatments were further subjected to desorption to test their retention capacity. The statistical analysis showed that two types of soil amended biochars (slow pyrolysis biochar and fast pyrolysis biochar) retained E. coli significantly better. The adsorption capacity of biochar was directly proportional to its porosity and inversely proportional to its ash content. The two types of soil amended biochar were shortlisted based on sorption and retention capacity and were used as treatments in the field study.A sixty-day study was conducted using field lysimeters to evaluate the effectiveness of soil amended biochar in removing or reducing the leaching of fecal coliforms (E. coli) from poultry manure. Lysimeter with only soil was used as control and the shortlisted biochars (slow pyrolysis biochar and fast pyrolysis biochar) were used as treatments. In the biochar-amended treatments, the top 0.05 m of soil was amended with biochar in a proportion of 1:99 biochar:soil. Poultry manure was spread over the soil in all lysimeters. The lysimeters were protected from natural rainfall, and the simulated rainfall was applied as 4 events over a sixty day period. Both soil (3 sampling depths) and leachate samples were collected and analyzed at predetermined time intervals. In the experiment, E. coli and total coliform were found to leach down through the soil profiles, and their concentrations decreased with soil depth and time. The statistical analysis of soil samples and leachate showed that the concentration of E. coli in the treatments at the three sampling depths and in the leachate were significantly different from control (P ⤠0.05), which is attributed to the effectiveness of the treatments in reducing the leaching of fecal coliforms. However, the concentration of total coliforms was significant (P ⤠0.05) on certain intervals and insignificant in the others; this can be attributed to already present total coliforms in the soil system and effectiveness of the treatments to hinder coliform transport. Soil biochar amendment was thus seen to be effective in reducing the leaching of fecal coliforms through soil profiles and providing fecal coliforms free leachate.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,001 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,001 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,001 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,001 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,002 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».