The study aimed to explore the efficacy of different nitrogen management strategies, including NPK fertilizers, nitrification inhibitors like DMPP, and biochar at varying application rates. By testing combinations of these treatments, the researchers sought to determine their impact on enhancing nitrogen retention, improving crop productivity, and mitigating greenhouse gas emissions, particularly in calcareous soils.
Agriculture in calcareous soils, common in arid and semi-arid regions such as Asia, North Africa, and Australia, faces significant N management challenges. The high pH of these soils accelerates the conversion of ammonium (NH4+) to nitrate (NO3‒), leading to rapid nitrogen loss through leaching and denitrification. This creates a “high input-low utilization-high loss” nitrogen cycle, which poses a major challenge for soil health, crop productivity, and environmental sustainability. To address this, nitrification inhibitors and biochar are commonly suggested strategies, but their comparative effectiveness and mechanisms, particularly in calcareous soils, remain underexplored.
A study (DOI: 10.48130/nc-0025-0013) published in Nitrogen Cycling on 13 January 2026 by Tongbin Zhu’s team, Institute of Karst Geology, highlights the effectiveness of DMPP in improving nitrogen use efficiency and reducing N2O emissions in calcareous soils, offering a sustainable solution for enhancing crop productivity and mitigating environmental impacts.
The study explored the impact of different fertilization treatments on crop yield, N uptake, NUE, soil properties, and N2O emissions over two growing seasons. Researchers tested eight treatments, including NPK + DMPP, NPK + biochar (BC10 and BC30), and combinations of these, with varying application rates. Results indicated that NPK + DMPP significantly improved crop yield, N uptake, and NUE, with increases of 30.8%–49.1%, 19.0%–48.9%, and 14.4%–17.9%, respectively, compared to other treatments. Additionally, DMPP reduced N2O emissions by 77.0%–85.1%. The treatment also led to lower soil pH and organic carbon content. DMPP’s effectiveness was attributed to its inhibition of ammonia-oxidizing bacteria (AOB), reducing nitrification rates and extending the residence time of inorganic nitrogen, which enhanced nitrogen retention and crop utilization. In contrast, biochar, while promoting microbial N immobilization, accelerated nitrification and increased N2O emissions. Even when combined with DMPP, biochar did not alleviate these negative effects on NUE or greenhouse gas emissions. High biochar application rates (30 t ha‒1) resulted in reduced crop yield and NUE, mainly due to accelerated nitrification and higher nitrogen losses. Overall, the study underscores DMPP as a superior strategy for improving crop performance, NUE, and mitigating N2O emissions in calcareous soils, positioning it as a crucial nitrogen management tool.
In conclusion, DMPP stands out as the more effective option for enhancing nitrogen use efficiency and reducing N2O emissions in calcareous soils. By inhibiting nitrification and improving nitrogen retention, DMPP offers a sustainable solution for improving crop yields while mitigating greenhouse gas emissions. As agricultural practices continue to evolve, the findings of this study offer a strong foundation for advancing precision nitrogen management and achieving sustainable agricultural production in calcareous regions worldwide.
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References
DOI
10.48130/nc-0025-0013
Original Souce URL
https://doi.org/10.48130/nc-0025-0013
Funding information
This research was supported by the Key R&D Programs of Guangxi (Grant No. Guikenong AB241484038), the Guangxi Science and Technology Planning Project (Grant No. 2023GXNSFFA026010), the CAGS Research Fund (Grant No. YYWF 2023015), and the Geological Survey Project, China (Grant No. DD20240095).
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Nitrogen Cycling is a multidisciplinary platform for communicating advances in fundamental and applied research on the nitrogen cycle. It is dedicated to serving as an innovative, efficient, and professional platform for researchers in the field of nitrogen cycling worldwide to deliver findings from this rapidly expanding field of science.