Oxygen regulates nitrous oxide production directly in agricultural soils.
Oxygen regulates nitrous oxide production directly in agricultural soils.
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DOI：
10.1021/acs.est.9b03089
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发表时间：
2019-10
影响因子：
11.4
通讯作者：
Xiao-Zong Song;X. Ju;C. Topp;R. Rees
中科院分区：
文献类型：
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作者：
Xiao-Zong Song;X. Ju;C. Topp;R. Rees
在结构良好的农业土壤中，氧气(O2)在调节一氧化二氮(N2O)的产生中起着关键的作用，但人们对此知之甚少。我们研究了在一系列环境条件(温度、水分、氨氮、硝酸盐、溶解有机碳等)下，在一个典型的集约化种植系统中，原位O2动态对N2O产生的影响。气候和管理(施肥、灌溉、降水和温度)及其交互作用显著影响土壤O2和N2O浓度(P<；0.05)。土壤O2浓度与土壤N2O浓度的相关性最显著(r=-0.71)，与温度、充水孔隙和氨氮浓度的相关系数分别为0.30、0.25和0.26。土壤N2O浓度随土壤O2浓度的降低呈指数增加。N处理和施肥与灌溉/降水事件的指数模型分别预测了土壤N2O浓度变化的74-90%和58%。我们的结果表明，土壤O2状态是N2O产生的最直接、最直接和最决定性的环境触发因素，超过了其他因素的影响，并且可能是一个综合各种复杂相互作用变量的综合影响的关键变量。这项研究为开发更敏感的方法来预测和通过适当的管理干预减少农业土壤的N2O排放提供了新的机会。
Oxygen (O2) plays a critical and yet poorly understood role in regulating nitrous oxide (N2O) production in well-structured agricultural soils. We investigated the effects of in situ O2 dynamics on N2O production in a typical intensively managed Chinese cropping system under a range of environmental conditions (temperature, moisture, ammonium, nitrate, dissolved organic carbon etc.). Climate and management (fertilization, irrigation, precipitation and temperature), and their interactions significantly affected soil O2 and N2O concentrations (P<0.05). Soil O2 concentration was the most significant factor correlating with soil N2O concentration (r= -0.71) when compared with temperature, water-filled pore space and ammonium concentration (r= 0.30, 0.25 and 0.26, respectively). Soil N2O concentration increased exponentially with decreasing soil O2 concentrations. The exponential model of N treatments and fertilization with irrigation/precipitation events predicted 74-90% and 58% of the variance in soil N2O concentrations, respectively. Our results highlight that soil O2 status is the proximal, direct and the most decisive environmental trigger for N2O production outweighing the effects of other factors, and could be a key variable integrating the aggregated effects of various complex interacting variables. This study offers new opportunities for developing more sensitive approaches to predicting and through appropriate management interventions mitigating N2O emissions from agricultural soils.