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The incorporation of crop stover into the soil improves soil fertility and crop productivity by increasing C sequestration and reducing the emission of greenhouse gases among other parameters. Interactions between crop stover management and N fertilization could help to improve C sequestration while increasing productivity. The objective of this study was to evaluate the impact of incorporating or removing corn (Zea mays L.) stover, in combination with different N fertilization rates (0, 100, 200, and 300 kg N ha–1), on corn production, soil organic carbon (SOC), and soil mineral nitrogen (SMN) in high production areas. We performed two field experiments (Exp. 1 and 2) for 3 yr under sprinkler irrigation. Over the duration of the experiment (short‐term period), stover management did not affect corn production or SMN levels, while high average grain yields were achieved (16–20 Mg ha–1) when N was applied. After 3 yr, removing the stover reduced SOC levels by approximately 0.82 and 1.06 g C m–2 (0–30‐cm depth) in 2012 in Exp. 1 and 2, respectively. The amounts of corn stover incorporated were higher than 16 Mg ha–1 yr–1 of dry matter. Our data suggest that returning stover to the soil has a positive short‐term impact on soil quality without grain yield penalties. Although selling the stover provides a short‐term economic advantage, continuous stover removal may cause significant soil degradation in the future.

Core Ideas Grain yield, biomass, N uptake, SPAD units, soil N levels and N efficiciencies were affected by the N application rate. Maximum grain yields required 203 kg N ha−1 of available N in the 0‐ to 30‐cm layer soil. Sampling to a depth of 0 to 30 cm provided similar correlations than sampling to 0 to 60 and 0 to 90 cm. Mineral N fertilization increased soil organic C stock. Nitrogen is a key determinant of growth and grain yield (GY) in maize (Zea mays L.) and is therefore economically and environmentally important. We investigated the performance of maize crops in a 12‐yr experiment (2002–2007, 2010–2015) under sprinkler irrigation in a petrocalcic calcixerept soil in northeastern Spain, with controlled mineral N application rates (0, 100, 150, 200, 250, 300, and 400 kg N ha−1 yr−1). The application rate affected maize GY, biomass, N uptake, SPAD units, soil N levels, N efficiencies, and soil organic carbon (SOC). Average maximum GY's (∼15 Mg ha−1) required 203 kg N ha−1 of available N (defined as initial soil NO3− plus N fertilizer) in the 0‐ to 30‐cm horizon, confirming the importance of the soil N content. Nitrate levels in the 0‐ to 30‐cm horizon for maximum yields achieved a R2 value in the plateau fitting model similar to the 0‐ to 60‐ and 0‐ to 90‐cm horizons. The GY's increased at a rate of 192 kg ha−1 yr−1, suggesting a combination of genetic improvement in the hybrids and also an improvement in agronomic management. The 200 kg N ha−1 fertilizer treatment achieved almost the highest GY's (∼14 Mg ha−1) with simultaneous high nitrogen use efficiency (NUE) (0.83 kg kg−1). Mineral N fertilization also increased the stock of SOC in the 0‐ to 30‐cm horizon.

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