Mapping Global Nitrogen Mineralization Rates: A Climate–Soil Perspective

Abstract

Global modeling of soil net nitrogen mineralization rates (Nmin) is challenging due to the absence of an integrated system that accurately quantifies their magnitude and spatial distribution. This study addresses this gap by analyzing the spatial variability of Nmin using a comprehensive dataset of 1347 Nmin measurements from 291 studies, combined with high-resolution climate and soil data. Our global maps reveal average Nmin rates of 1.68, 5.17, and 1.71 mg N kg−1 day−1 for cropland, forest, and grassland soils, respectively. Integrating projected climate scenarios, we also explore potential shifts in Nmin patterns under future varying environmental conditions. Key factors influencing Nmin include mean annual precipitation, soil pH, total nitrogen, carbon-to-nitrogen ratio, and microbial biomass nitrogen, with microbial biomass nitrogen playing a particularly significant role. These findings underscore the potential of global-scale Nmin modeling to support informed decision-making, facilitating optimal fertilizer use and management practices that promote soil health and sustained productivity.