He Gang, Deng Danli, Delgado-Baquerizo Manuel, Liu Wenzhi, Zhang Quanfa
Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, P.R. China.
Hubei Field Observation and Scientific Research Stations for Water Ecosystem in Three Gorges Reservoir, China Three Gorges University, Yichang, 443002, P.R. China.
Adv Sci (Weinh). 2025 Feb;12(8):e2406857. doi: 10.1002/advs.202406857. Epub 2024 Dec 31.
Denitrification and anaerobic ammonium oxidation (anammox) are the major microbial processes responsible for global nitrogen (N) loss. Yet, the relative contributions of denitrification and anammox to N loss across contrasting terrestrial and aquatic ecosystems worldwide remain unclear, hampering capacities to predict the human alterations in the global N cycle. Here, a global synthesis including 3240 observations from 199 published isotope pairing studies is conducted and finds that denitrification governs microbial N loss globally (79.8±0.4%). Significantly, anammox is more important in aquatic than terrestrial ecosystems worldwide and can contribute up to 43.2% of N loss in global seawater. Global maps for N loss associated with denitrification and anammox are further generated and show that the contribution of anammox to N loss decreases with latitude for soils and sediments but generally increases with substrate depth. This work highlights the importance of anammox as well as denitrification in driving ecosystem N losses, which is critical for improving the current global N cycle model and achieving sustainable N management.
反硝化作用和厌氧氨氧化是导致全球氮损失的主要微生物过程。然而，在全球不同的陆地和水生生态系统中，反硝化作用和厌氧氨氧化对氮损失的相对贡献仍不明确，这妨碍了预测全球氮循环中人类活动影响的能力。在此，我们进行了一项全球综合研究，纳入了来自199项已发表的同位素配对研究的3240个观测数据，发现反硝化作用在全球微生物氮损失中占主导地位（79.8±0.4%）。值得注意的是，在全球范围内，厌氧氨氧化在水生生态系统中比在陆地生态系统中更重要，在全球海水中，其对氮损失的贡献可达43.2%。我们还进一步绘制了与反硝化作用和厌氧氨氧化相关的全球氮损失地图，结果表明，对于土壤和沉积物而言，厌氧氨氧化对氮损失的贡献随纬度降低，但一般随底物深度增加。这项研究突出了厌氧氨氧化以及反硝化作用在推动生态系统氮损失方面的重要性，这对于改进当前的全球氮循环模型和实现可持续氮管理至关重要。
