Synergistic effects of precipitation events and long-term N addition on N2O emissions in a temperate meadow steppe, Northeast China
Synergistic effects of precipitation events and long-term N addition on N2O emissions in a temperate meadow steppe, Northeast China
复制标题
DOI：
10.1016/j.agrformet.2023.109860
复制
发表时间：
2023-12-10
影响因子：
6.2
通讯作者：
Sun，Wei
中科院分区：
文献类型：
--
作者：
Gao，Weifeng;Zhao，Tianhang;Sun，Wei
降水事件和氮素添加对半干旱草地生态系统氧化亚氮排放具有重要的调控作用。然而，降水事件，长期的N添加，以及它们之间的相互作用对N2 O排放的影响，在很大程度上仍然不清楚。我们进行了一个围隔实验，以研究长期的N添加（0和10 g N m-2 yr-1，从2011年到2020年）如何影响N2 O排放响应梯度的人工降水事件（0，5，10，20和50 mm）。降水事件对N2 O排放的脉冲效应是由于微生物活性和基质可用性的刺激。降水事件显着抛物线增加累积N2 O排放量。长期的N添加显著增强了累积N2 O排放量对降水事件的响应。降水事件和长期的N添加协同提高累积N2 O排放。水填充孔隙空间和铵态氮含量是最重要的因素驱动的时间动态和积累的N2 O排放的降水事件和长期的N添加。研究表明，氮的添加影响了N2 O排放对降水事件的响应，这对于理解N2 O排放对全球变化的响应至关重要。
Precipitation events and nitrogen (N) addition play important roles in regulating nitrous oxide (N2O) emissions in semi-arid grassland ecosystems. The effects of precipitation events, long-term N addition, and their interaction on N2O emissions, however, remain largely unclear. We conducted a mesocosm experiment to examine how long-term N addition (0 and 10 g N m−2yr−1, from 2011 to 2020) affects N2O emission responses to a gradient of manipulated precipitation events (0, 5, 10, 20, and 50 mm). The precipitation events had pulsing effects on N2O emissions due to the stimulation of microbial activity and substrate availability. Precipitation events significantly parabolically increased cumulative N2O emissions. Long-term N addition substantially enhanced cumulative N2O emissions response to precipitation events. The precipitation events and long-term N addition synergistically improved cumulative N2O emissions. The water-filled pore space and ammonium nitrogen content were the most important factors driving the temporal dynamics and accumulation of N2O emissions following the precipitation events and long-term N addition. Our study indicates that N addition affects the N2O emissions responses to precipitation events, which are essential for understanding the response of N2O emissions to global change.