Nitrous oxide emissions from cultivated black soil: A case study in Northeast China and global estimates using empirical model
Nitrous oxide emissions from cultivated black soil: A case study in Northeast China and global estimates using empirical model
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耕作黑土的一氧化二氮排放：中国东北地区的案例研究和使用经验模型的全球估算
DOI：
10.1002/2014gb004871
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发表时间：
2014-11-01
影响因子：
5.2
通讯作者：
Zhu, Tongbin
中科院分区：
文献类型：
--
作者：
Chen, Zengming;Ding, Weixin;Zhu, Tongbin
粪肥施用可有效促进土壤固碳，但其对 N2O 排放的影响尚不清楚。在东北玉米种植黑土上进行田间试验，采用无机肥（NPK）、75%无机肥N+25%猪（PM1）或鸡（CM1）粪N、50%无机肥N+50%猪（PM2）或鸡（CM2）粪N、不施氮肥（CK）6个处理。 N2O年排放量显着增加，从CK的0.34kgNha(-1)增加到NPK的0.86kgNha(-1)，PM1、CM1、PM2和CM2分别增加到1.65、1.02、1.17和0.93kgNha(-1)。 N-15追踪研究表明，总N2O的71-79%与30-70%充水孔隙空间（WFPS）的硝化作用有关，而异养硝化作用在30%和70% WFPS时分别贡献了总N2O的49%和25%。在孵化过程中，只有当硝酸盐和葡萄糖以 60% WFPS 一起施用时，N2O 排放才会受到刺激，这表明反硝化是碳限制的。由于较高的分解性，PM 对反硝化作用的影响比 CM 更强，并且较高肥料施用量下 N2O 排放量较低与矿物氮供应减少有关。在编制了全球数据库并建立了将 N2O 排放量（kgNha(-1)）与降水量（P-r, m）和化肥施氮量（N-r, kg N ha(-1)）（N2O = 1.533P(r) + 0.0238P(r)N(r)）相关联的经验模型后，全球施用无机肥 N 的耕作黑土的年 N2O 排放量估计为 347 Gg N。认为中国耕作黑土的 N2O 排放量较低，主要是由于降水量少和活性有机碳的有效性，并且会受到粪肥施用的刺激；因此，由于施用粪肥会增加土壤有机碳固存，因此应考虑增加 N2O 排放量。
Manure application is effective in promoting soil carbon sequestration, but its impact on N2O emission is not well understood. A field experiment was conducted in a maize-cultivated black soil in Northeast China with six treatments: inorganic fertilizer (NPK), 75% inorganic fertilizer N plus 25% pig (PM1) or chicken (CM1) manure N, 50% inorganic fertilizer N plus 50% pig (PM2) or chicken (CM2) manure N, and no N fertilizer (CK). Annual N2O emission significantly increased from 0.34kgNha(-1) for CK to 0.86kgNha(-1) for NPK and further to 1.65, 1.02, 1.17, and 0.93kgNha(-1) for PM1, CM1, PM2, and CM2, respectively. A N-15 tracing study showed that 71-79% of total N2O was related to nitrification at 30-70% water-filled pore space (WFPS), and heterotrophic nitrification contributed 49% and 25% to total N2O at 30% and 70% WFPS, respectively. In an incubation, N2O emission was only stimulated when nitrate and glucose were applied together at 60% WFPS, indicating that denitrification was carbon limited. PM had a stronger effect on denitrification than CM due to higher decomposability, and the lower N2O emission at higher manure application rate was associated with decreased mineral N supply. After compiling a worldwide database and establishing an empirical model that related N2O emissions (kgNha(-1)) to precipitation (P-r, m) and fertilizer N application rate (N-r, kg N ha(-1)) (N2O = 1.533P(r) + 0.0238P(r)N(r)), annual N2O emission from global-cultivated black soil applied with inorganic fertilizer N was estimated as 347 Gg N. Our results suggested that N2O emission from cultivated black soils in China was low primarily due to low precipitation and labile organic carbon availability, and would be stimulated by manure application; thus, increased N2O emission should be taken into consideration as applying manure increases soil organic carbon sequestration.