From Disruption to Restoration: Global Impacts of Soil Salinity and Its Mitigation Strategies on Ecosystem Nitrogen Cycling

作者：Nathan Okoth Oduor, Ahmed S. Elrys, Manal A. Alnaimy, Tracy Opande, Di Feng, Yves Uwiragiye, Xiaoqian Dan, Shuirong Tang, Tongbin Zhu, Lei Meng, Jinbo Zhang, Christoph Müller · 发表于：Global Change Biology · 年份：2025 · DOI：10.1111/gcb.70487 · 被引用次数：14 · 研究领域：Soil Carbon and Nitrogen Dynamics、Soil and Water Nutrient Dynamics、Soil erosion and sediment transport

Salinity impairs soil health by disrupting microbial activity and altering soil physicochemical properties, ultimately undermining ecosystem resilience and productivity. Yet, the effect of salinity and its mitigation strategies on soil nitrogen (N) cycling and plant ammonium and nitrate uptake and N use efficiency is not well established on a global scale. Through a meta-analysis of 3422 paired observations from 309 publications, we found that salinity significantly alters soil N dynamics across multiple pathways. It inhibited the nitrification process by reducing microbial biomass, leading to a substantial accumulation of ammonium (+145%) and nitrite (+203%), while significantly suppressing biological N fixation (-82%). These shifts significantly increased plant uptake of ammonium but reduced that of nitrate and total N, ultimately contributing to a decline in crop yield by 9.5%. Accumulated ammonium in soil also increased ammonia volatilization by 158%. The effect of salinity on soil N availability was context-specific, exhibiting greater effects under high salinity levels, especially in natural ecosystems, arid zones, and alkaline soils. Contrastingly, salinity mitigation treatments led to significant improvements across multiple N pathways. They enhanced soil N pools, including increased biological N fixation and available and total N concentrations. These changes supported greater plant N uptake, resulting in increased N use efficiency and crop yield. However, these bene...