Fertilizer Intensity, Agricultural Productivity, and Agricultural Emissions: Ratio Decomposition in a 24-Country Panel

Abstract

Fertilizer use can raise agricultural output while increasing emissions, making ratio-based environmental indicators potentially misleading. This study evaluates these relationships in a panel of 24 countries from five regions and advances sustainability assessment by distinguishing relative emissions efficiency from absolute environmental pressure. The productivity analysis covers 2002–2022, whereas the source-verified environmental series covers 2002–2019. Country and year fixed-effects models use Driscoll–Kraay standard errors. Fertilizer intensity is positively associated with land productivity (elasticity = 0.182; SE = 0.032), absolute agricultural emissions (0.123; SE = 0.026), and emissions per hectare (0.085; SE = 0.016), but negatively associated with emissions intensity (−0.098; SE = 0.028). The emissions-intensity result reflects faster growth of the production denominator and does not demonstrate absolute decoupling. The productivity estimate remains positive with lagged fertilizer, first differences, regional trends, macroeconomic controls, an irrigation subsample, alternative covariance estimators, and sequential country exclusion. The Agriculture Orientation Index is unrelated to productivity and absolute emissions, although it is negatively associated with emissions intensity. The findings support nutrient-use efficiency and joint reporting of absolute, land-based, and intensity indicators.