有机肥组分特征对黑土N2O排放的影响研究

有机肥正被广泛用于东北黑土地固碳培肥，为探究其影响N₂O排放的效应及碳组分机制，试验设置在两个氮水平下(0、100 mg/kg)，不加有机肥(CK)和6个添加不同原料制成的有机肥，共14个处理，动态测定培养期(365 d)N₂O排放通量，并分析有机肥性质及结构特征。结果表明，施用有机肥总体上促进黑土N₂O排放，特别是加氮条件下；但是在不同培养阶段，不同种类有机肥对N₂O排放的影响存在显著差异。培养前期有机肥对N₂O排放的快速刺激作用主要与其带入的无机氮含量正相关，但是活性有机碳与木质素酚“共代谢”分解可能通过促进微生物对氮素的同化作用进而削减有机肥对N₂O排放的促进作用。在培养中后期，纤维素和半纤维素成为有机肥调控N₂O排放的关键组分。氮添加有利于后期惰性木质素单体分解，促进含氮有机组分矿化，进而增强N₂O排放对有机肥的正响应。综上，有机肥组分特征影响其可分解性进而调控黑土N₂O排放，在制定...

Effects of Manure Chemical Compositions on N2O Emissions from Black Soils

Manure is now widely used for C sequestration and fertility improvement in black soils of northeast China, in order to explore the mechanisms underlying the responses of N2O emissions to manure application. The experiment was set up at two nitrogen (N) levels (0 and 100 mg N/kg) without manure application and six manure-added treatments were set by adding various kinds of composts, resulting in 14 treatments in total. The N2O fluxes was measured during the whole incubation period (365 days) and analyzed the properties and compositions of manure. It was showed that the application of manure promoted N2O emissions in general, especially under N100 treatment. However, there were significant differences in the effects of different manures and at different incubation stages. The rapid response of N2O emission to manure application at the early stage was mainly attribute to the input of inorganic N of manure, but the labile organic C and lignin phenols might reduce N2O emissions by co-metabolism that could promote microbial N immobilization. Subsequently, celluloses and hemicelluloses became the key factors for manure in regulating N2O emission that were negatively related to N2O emissions without N addition; while, N addition might promote the decomposition of lignin vanillyl which could facilitate N release from nitrogenous organic matter and N2O production. Overall, our study suggested that the chemical compositions of manure affect the decomposition process and thus regulate N2O emission, which should be taken into account in developing measures to improve the SOC and fertility of black soils by manure application.