title: Correlating denitrifying catabolic genes with N2O and N2 emissions from swine slurry composting.
abstract: This work evaluated N dynamics that occurs over time within swine slurry composting piles. Real-time quantitative PCR (qPCR) analyzes were conducted to estimate concentrations of bacteria community harboring specific catabolic nitrifying-ammonium monooxygenase (amoA), and denitrifying nitrate- (narG), nitrite- (nirS and nirG), nitric oxide- (norB) and nitrous oxide reductases (nosZ) genes. NH3-N, N2O-N, N2-N emissions represented 15.4 ± 1.9%, 5.4 ± 0.9%, and 79.1 ± 2.0% of the total nitrogen losses, respectively. Among the genes tested, temporal distribution of narG, nirS, and nosZ concentration correlated significantly (p<0.05) with the estimated N2 emissions. Denitrifying catabolic gene ratio (cnorB+qnorB)/nosZ ≥ 100 was indicative of N2O emission potential from the compost pile. Considering our current empirical limitations to accurately measure N2 emissions from swine slurry composting at field scale the use of these catabolic genes could represent a promising monitoring tool to aid minimize our uncertainties on biological N mass balances in these systems.
authors.affiliation: Federal University of Santa Catarina, 88034-001 Florianópolis, SC, Brazil. graciangnes@gmail.com
authors.forename: G
authors.initials: G
authors.lastname: Angnes
authors.forename: R S
authors.initials: RS
authors.lastname: Nicoloso
authors.forename: M L B
authors.initials: ML
authors.lastname: da Silva
authors.forename: P A V
authors.initials: PA
authors.lastname: de Oliveira
authors.forename: M M
authors.initials: MM
authors.lastname: Higarashi
authors.forename: M P
authors.initials: MP
authors.lastname: Mezzari
authors.forename: P R M
authors.initials: PR
authors.lastname: Miller
mesh_terms: D000641:Ammonia / Q000032:analysis; D000818:Animals; D002245:Carbon Dioxide / Q000032:analysis; D058440:Denitrification / Q000235:genetics*; D005798:Genes, Bacterial / Q000235:genetics*; D006813:Humidity; D008697:Methane / Q000032:analysis; D058465:Nitrification / Q000235:genetics; D009584:Nitrogen / Q000032:analysis*; D009609:Nitrous Oxide / Q000032:analysis*; D012987:Soil; D034421:Sus scrofa; D013696:Temperature; D013997:Time Factors
chemical_list: D012987:Soil; D002245:Carbon Dioxide; D000641:Ammonia; D009609:Nitrous Oxide; D009584:Nitrogen; D008697:Methane