title: N₂O emissions and nitrogen transformation during windrow composting of dairy manure.
abstract: Windrow composting involves piling and regularly turning organic wastes in long rows, being in the succession of static standing periods between two consecutive pile turnings as well as a period of pile turning. N2O emissions and N transformation were investigated during the processes of windrow composting. In contrast to the conventional understanding, we observed that N2O concentrations inside compost materials were significantly higher after pile turning (APT) than before pile turning (BPT). Pile turning triggered a burst of N2O production rather than simple gaseous N2O escape from the stirred compost. Denitrification was the dominant pathway in pile turning because the observed [Formula: see text] and [Formula: see text] concentrations were significantly lower APT compared to BPT. The sudden exposure of O2 severely inhibited N2O reductase, which can block the transformation of N2O to N2 and thus caused an increase of N2O emission. As the [Formula: see text] and [Formula: see text] concentrations rose during the following 48 standing hours, nitrification dominated N transformation and did not cause an increase of surface N2O emissions. Thus, pile turning resulted in a dramatic conversion of N transformation and strongly influenced its flux size. It was also found that high [Formula: see text] was accumulated in the compost and had a strong correlation with N2O emissions. Practical methods regulating nitrite and the frequency of pile turning would be useful to mitigate N2O emissions in manure composting.
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, 210008 Nanjing, PR China.
authors.forename: Ruirui
authors.initials: R
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, 210008 Nanjing, PR China.
authors.forename: Yiming
authors.initials: Y
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, 210008 Nanjing, PR China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, 210008 Nanjing, PR China.
authors.forename: Shiping
authors.initials: S
authors.lastname: Wei
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, 210008 Nanjing, PR China.
authors.forename: Zhongwang
authors.initials: Z
authors.lastname: Jing
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, 210008 Nanjing, PR China. Electronic address: xglin@issas.ac.cn.
authors.forename: Xiangui
authors.initials: X
authors.lastname: Lin
mesh_terms: D000818:Animals; D002417:Cattle; D003612:Dairying; D005260:Female; D008372:Manure; D009584:Nitrogen / Q000737:chemistry*; D009609:Nitrous Oxide / Q000737:chemistry*; D012987:Soil; D012988:Soil Microbiology
chemical_list: D008372:Manure; D012987:Soil; D009609:Nitrous Oxide; D009584:Nitrogen
keywords: Denitrification; N(2)O emissions; Nitrification; Pile turning; Windrow composting