Mitigating CO2 and N2O emissions in salt-affected agroecosystems through fertilization and irrigation optimization: A meta-analysis

CONTEXT: Salt-affected soils are increasingly widespread in agricultural landscapes, but their responses to management practices in terms of greenhouse gas (GHG) emissions remain poorly constrained. Understanding how agricultural management influences GHG emissions in these soils is therefore essential for developing sustainable strategies that alleviate salinity stress, sustain crop productivity, and minimize environmental impacts. OBJECTIVE: This study aims to quantitatively assess the impacts of different fertilization and irrigation practices on CO2 and N2O emissions in salt-affected soils. METHODS: A meta-analysis of 68 peer-reviewed studies was conducted to address this objective. RESULTS AND CONCLUSIONS: The results showed that, from a mitigation perspective, a single biochar application was the most effective option, reducing carbon dioxide (CO2) emissions by 10.8% (p = 0.2) and nitrous oxide (N2O) emissions by 25.5% (p = 0.1) compared to conditions without fertilizer application. However, when agronomic performance was also considered, the organic fertilizer combined with nitrogen (N) application emerged as the most balanced fertilization strategy, reducing GHG emissions while sustaining crop productivity. Similarly, Irrigation regimes below 60% of field capacity (FC) substantially reduced CO2 (−41.3%, p