Precipitation legacies amplify ecosystem nitrogen losses from nitric oxide emissions in a Pinyon–Juniper dryland
Precipitation legacies amplify ecosystem nitrogen losses from nitric oxide emissions in a Pinyon–Juniper dryland
复制标题
降水遗留物加剧了 Pinyon-Juniper 旱地一氧化氮排放造成的生态系统氮损失
DOI：
10.1002/ecy.3930
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发表时间：
2023
期刊：
影响因子：
4.8
通讯作者：
Homyak, Peter M.
中科院分区：
文献类型：
--
作者：
Krichels, Alexander H.;Greene, Aral C.;Jenerette, G. Darrel;Spasojevic, Marko J.;Glassman, Sydney I.;Homyak, Peter M.
气候变化正在增加降水的变异性，改变土壤干湿事件的频率和季节性降水的分布。降水的这些变化可以改变氮（N）循环，刺激一氧化氮（NO）排放（一种高浓度的空气污染物），这可能会根据过去降水的遗产而变化，并代表生态系统氮损失的途径。为了确定降水遗产是否影响NO排放，我们排除或增加降水在冬季生长季节在Pinyon-Juniper旱地和测量原位NO排放实验湿润。我们发现，排除和增加冬季降水的遗产增加了第二年夏季早期的NO排放量;冬季降水排除区（2750 ± 972 μg N-NO m−2）和冬季水添加区（2449 ± 408 μg N-NO m−2）的累积NO排放量高于对照区（1506 ± 397 μg N-NO m−2）。NO排放量的增加与以前的降水排除与无机氮积累，而NO排放量的增加与以前的水除了与微生物生物量的上升趋势。降水遗产可以加速土壤NO的排放，并可能放大生态系统N的损失，以应对更多变的降水。
Climate change is increasing the variability of precipitation, altering the frequency of soil drying‐wetting events and the distribution of seasonal precipitation. These changes in precipitation can alter nitrogen (N) cycling and stimulate nitric oxide (NO) emissions (an air pollutant at high concentrations), which may vary according to legacies of past precipitation and represent a pathway for ecosystem N loss. To identify whether precipitation legacies affect NO emissions, we excluded or added precipitation during the winter growing season in a Pinyon–Juniper dryland and measured in situ NO emissions following experimental wetting. We found that the legacy of both excluding and adding winter precipitation increased NO emissions early in the following summer; cumulative NO emissions from the winter precipitation exclusion plots (2750 ± 972 μg N‐NO m−2) and winter water addition plots (2449 ± 408 μg N‐NO m−2) were higher than control plots (1506 ± 397 μg N‐NO m−2). The increase in NO emissions with previous precipitation exclusion was associated with inorganic N accumulation, while the increase in NO emissions with previous water addition was associated with an upward trend in microbial biomass. Precipitation legacies can accelerate soil NO emissions and may amplify ecosystem N loss in response to more variable precipitation.