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This study was conducted based on the open-access global database of field experiments assembled by (Wang et al., 2024). We complemented the published database with additional metadata on soil, climate, and management factors. In this study we test the different type of fertilizer application compare with non-fertilizer application on maize yield and different types of nitrogen losses like N2O, NH3 and NO₃⁻ leaching. We evaluated different fertilizer treatments, which included mineral, organic, enhanced-efficiency, and combined mineral-organic fertilizers. To permit a more detailed mechanistic exploration of management and environmental drivers of Nr losses than was possible in the original publication (Wang et al., 2024), we systematically enriched this dataset by retrieving and digitising additional variables that were reported in the source publications. Specifically, the original 312 publications were re-examined to obtain: Number of fertilizer split applications (classified as once or multiple). Total irrigation water applied during the growing season (mm season⁻¹) when reported. Furthermore, using the exact geographical coordinates and experimental years provided in the database, the following climatic from (Fick and Hijmans, 2017) and crop-water (Mialyk et al., 2024) variables were derived for every site: Growing degree days (GDD, °C day, base 0 °C) from sowing to physiological maturity. Aridity index (AI = mean annual precipitation) and temperature seasonality (TS) based on GYGA_ED maps. Soil properties (pH, soil organic carbon content, clay percentage, and bulk density) that were missing in the original database were gap-filled using the ISRIC SoilGrids system at 250 m resolution. After incorporation of these newly extracted and derived variables and rigorous quality assurance, the final enhanced dataset retained the original 3,412 maize observations but with substantially expanded metadata, providing the most detailed global compilation currently available for simultaneous analysis of maize yield responses and multiple Nr loss pathways under contrasting management and environmental conditions.