title: Quantitative Effects of Biochar Oxidation and Pyrolysis Temperature on the Transport of Pathogenic and Nonpathogenic Escherichia coli in Biochar-Amended Sand Columns.
abstract: The present study quantifies the transport of Escherichia coli pathogenic O157:H7 and nonpathogenic K12 strains in water-saturated Quincy sand (QS) columns amended with oxidized (OX) or unoxidized (UO) pine wood (PW) or pine bark (PB) biochar produced at either 350 or 600 °C. Our results showed that (1) the addition of oxidized biochar into QS columns enhanced the transport of E. coli O157:H7 by 3.1 fold compared to the unoxidized counterparts, likely because of an increase in the repulsive forces due to their higher negative charge densities. (2) The retention of E. coli O157:H7 was 3.3 fold higher than that of E. coli K12 in all biochar-amended sand columns. (3) Increased application rates of unoxidized PW600 biochar from 0 to 20 wt % led to a reduction in the transport of E. coli O157:H7 and K12 from 98 to 10% and from 95 to 70%, respectively. Our data showed that mixing sand with PW350-UO at a 20 wt % application rate almost completely retained the pathogenic E. coli in the subsurface, suggesting that utilizing sand mixed with biochar can act as a promising biofilter capable of protecting natural aquafers from pathogens.
authors.affiliation: Department of Microbiology, Benghazi University , Benghazi LYB2186, Libya.|Department of Crop and Soil Sciences, Washington State University , Pullman, Washington 99164, United States.
authors.forename: Waled
authors.initials: W
authors.lastname: Suliman
authors.affiliation: Department of Crop and Soil Sciences, Washington State University , Pullman, Washington 99164, United States.
authors.forename: James B
authors.identifier: http://orcid.org/0000-0002-0177-3342
authors.initials: JB
authors.lastname: Harsh
authors.affiliation: Soil Science Department, North Dakota State University , Fargo, North Dakota 58108, United States.
authors.forename: Ann-Marie
authors.initials: AM
authors.lastname: Fortuna
authors.affiliation: Biological Systems Engineering Department, Washington State University , Pullman, Washington 99164, United States.
authors.forename: Manuel
authors.identifier: http://orcid.org/0000-0002-9386-2632
authors.initials: M
authors.lastname: Garcia-Pérez
authors.affiliation: The Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University , Pullman, Washington 99164, United States.
authors.forename: Nehal I
authors.identifier: http://orcid.org/0000-0002-2319-2450
authors.initials: NI
authors.lastname: Abu-Lail
mesh_terms: D015169:Colony Count, Microbial; D004926:Escherichia coli; D048168:Escherichia coli K12; D019453:Escherichia coli O157; D012822:Silicon Dioxide / Q000494:pharmacology; D013696:Temperature; D014867:Water
chemical_list: D014867:Water; D012822:Silicon Dioxide