Carbon reduction starts in the fields: Precise fertilization assists climate control

In the face of climate change, agricultural emissions cannot be ignored. Nitrous oxide emissions can be significantly reduced through optimized nitrogen fertilizer management, application of slow-release fertilizers and precision agriculture technology. Scientific evidence supports policy intervention to promote sustainable farming.

Greenhouse gases play a vital role in the atmosphere. They act like a natural insulation layer on the earth, absorbing and re-releasing solar radiation, maintaining warmth on the earth’s surface and allowing life to flourish. However, since the Industrial Revolution, human activities have significantly increased the concentration of greenhouse gases in the atmosphere, breaking the original energy balance and leading to accelerated global climate change. The main greenhouse gases include carbon dioxide (CO₂), methane (CH₄) and nitrous oxide (N₂O)1. These gases absorb long-wave radiation released from the earth’s surface and slow down the escape of energy into space, thereby causing the earth’s temperature to rise, known as the greenhouse effect.1。

Among many greenhouse gases, nitrous oxide (N₂O), commonly known as laughing gas, has attracted much attention due to its potent warming potential and dual impact on the environment. Nitrous oxide is not only a long-lasting greenhouse gas, but also recognized by the scientific community as the most important substance that depletes the ozone layer.3. Although its concentration in the atmosphere is much lower than carbon dioxide, its warming potential is much higher than that of carbon dioxide and methane2. Especially in the agricultural field, nitrous oxide emissions caused by anthropogenic activities are particularly significant, making agriculture one of the main sources of anthropogenic nitrous oxide emissions.3. Agricultural soil emissions account for a large portion of U.S. nitrous oxide emissions, according to the U.S. Environmental Protection Agency (EPA)12。

This report aims to provide an in-depth look at how nitrous oxide produced in the soil becomes a potent greenhouse gas following the application of nitrogen fertilizers in agricultural production. The report will focus on elaborating the specific mechanism of nitrous oxide production, analyzing its unique characteristics as a greenhouse gas, and exploring various key factors that influence its emission in soil. Through detailed analysis of these aspects, it is expected to provide a more comprehensive understanding of the complex relationship between agricultural activities and climate change, and to provide scientific basis for formulating effective emission reduction strategies.

The soil nitrogen cycle is a complex biogeochemical process that is critical to maintaining the productivity of terrestrial ecosystems. The cycle involves several key steps, including ammonification, nitrification and denitrification17. First, nitrogen (N₂) in the atmosphere needs to be converted into a plant-usable form, mainly ammonia (NH₃), through nitrogen fixation.3. Nitrogen fixation is mainly accomplished by nitrogen-fixing microorganisms in the soil, including autogenic nitrogen-fixing bacteria and rhizobia that are symbiotic with leguminous plants. Once in the soil, ammonia is usually quickly converted into ammonium ions (NH₄⁺)3。

Next comes nitrification, an aerobic process accomplished by two different types of microorganisms3. First, ammonia-Oxidizing Bacteria (AOB) and Ammonia-Oxidizing Archaea (AOA) oxidize ammonium ions into nitrite (NO₂⁻). Then, Nitrite-Oxidizing Bacteria (NOB), such as Nitrosomobacter spp.Nitrobacter) and Nitrospira spp. (Nitrospira), will further oxidize nitrite to nitrate (NO₃⁻). It is worth noting that research in recent years has found that some microorganisms are able to complete the complete process of directly oxidizing ammonia to nitrate, which is called complete ammonia oxidation (comammox)17. Nitrification not only provides nitrates that are easily absorbed by plants, but may also cause a portion of the nitrogen to be emitted into the atmosphere in the form of nitrous oxide, especially when oxygen supply is limited.3。

Denitrification is an anaerobic process that occurs under anoxic conditions.3. When there is insufficient oxygen in the soil, such as under conditions of high soil moisture, some facultative anaerobic microorganisms use nitrate as an electron acceptor to gradually reduce it to nitrogen gas (N₂). During this process, a variety of nitrogen oxide intermediates are produced, including nitric oxide (NO) and nitrous oxide (N₂O). Therefore, denitrification is another important pathway for nitrous oxide production in soil3. In addition, some other microbial pathways, such as heterotrophic nitrification and codenitrification, are also thought to produce nitrous oxide4。

The application of nitrogen fertilizer in agricultural production, whether it is inorganic nitrogen fertilizer or organic nitrogen fertilizer, will significantly increase the content of available nitrogen in the soil, thereby disturbing the natural nitrogen cycle balance in the soil.12. The application of nitrogen fertilizer directly increases the concentration of ammonium and nitrate in the soil, providing more sufficient substrates for microorganisms involved in nitrification and denitrification.12. Different types of nitrogen fertilizers, such as urea, ammonium nitrate, etc., will undergo different transformation processes after being applied to the soil. These processes will also affect the emission of nitrous oxide.7. It is particularly worth noting that urea will rapidly hydrolyze in the soil to produce ammonia and carbon dioxide, causing the soil pH to rise. Changes in pH will further affect the rates of nitrification and denitrification as well as the production of nitrous oxide.22。

The relative contributions of nitrification and denitrification to nitrous oxide production will vary under different soil conditions and agricultural management practices. In general, nitrification is the main source of nitrous oxide in soil, usually under aerobic conditions4. However, under anoxic conditions, especially when soil moisture is high, denitrification becomes an important source of nitrous oxide3. In addition, the water saturation of the soil will also affect the final product of nitrous oxide during the denitrification process. Under high humidity, nitrous oxide is more likely to be further reduced to nitrogen.27. The pH value of soil is another key factor. It regulates nitrification and denitrification by affecting the activity of microorganisms and the reaction rate of enzymes, thereby affecting the production of nitrous oxide.14. Agricultural management practices, such as farming practices, can also indirectly affect nitrous oxide production by changing soil oxygen levels and microbial activity.35。

Global Warming Potential (GWP) is an important indicator used to compare the relative contributions of different greenhouse gases to global warming.1. GWP refers to the ratio of the radiative forcing caused by the emission of a unit mass of a certain greenhouse gas relative to the radiative forcing caused by the emission of the same mass of carbon dioxide within a specific time frame (usually 20 or 100 years).1. Since carbon dioxide is used as a reference gas, its GWP is defined as 1 for all time frames.1. The concept of GWP enables scientists and policymakers to evaluate and compare the emission impacts of different greenhouse gases under a unified framework, thereby better formulating emission reduction strategies.1。

According to the latest Sixth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) and data from the U.S. Environmental Protection Agency (EPA), nitrous oxide has a much higher global warming potential than carbon dioxide. The IPCC Sixth Assessment Report states that the GWP of nitrous oxide is 273 in both the 20-year and 100-year time frames.8. EPA data shows that nitrous oxide has a GWP of 265 over a 100-year timeframe.1. These values ​​clearly show that nitrous oxide is far more effective in warming the planet than other major greenhouse gases such as carbon dioxide and methane, even when emitting the same mass of gas2。

Not only does nitrous oxide have extremely high warming potential, it also has a long life cycle in the atmosphere, which means that its emissions will continue to affect the Earth’s climate system for a long time.1. Research shows that the average lifespan of nitrous oxide in the atmosphere is about 114 years1. Such a long life cycle makes the cumulative effect of nitrous oxide significant and has a profound impact on long-term climate change.

In addition to being a potent greenhouse gas, nitrous oxide plays an important role in atmospheric chemistry, particularly in the depletion of the ozone layer. Scientific research points out that nitrous oxide is one of the most important substances that depletes the ozone layer.3. When nitrous oxide rises to the stratosphere, it will participate in a series of chemical reactions, causing the decomposition of ozone molecules, thereby weakening the earth’s protective layer and increasing the impact of ultraviolet radiation on the surface.

The emission of nitrous oxide in soil after the application of nitrogen fertilizer is complexly affected by a variety of factors, including the type of nitrogen fertilizer, application method, soil properties, soil moisture and temperature, and the composition and activity of soil microbial communities.

Different types of nitrogen fertilizers have different chemical properties and transformation processes after they are applied to the soil, which in turn affects the emission of nitrous oxide. Research shows that nitrate-based fertilizers (such as ammonium nitrate) may produce higher nitrous oxide emissions than ammonium-based fertilizers (such as ammonium sulfate)7. As a widely used nitrogen fertilizer, urea hydrolyzes in the soil to produce ammonia, causing an increase in soil pH, which may promote denitrification and thereby increase nitrous oxide emissions.22. There are also differences in the nitrous oxide emission factors (i.e., the amount of nitrous oxide emitted as a percentage of the amount of nitrogen applied) of different nitrogen fertilizers7。

The application method of nitrogen fertilizer also has a significant impact on the emission pattern and total amount of nitrous oxide. Compared with one-time application, divided application of nitrogen fertilizer can better match the nutrient needs of crops at different growth stages, reduce excess nitrogen in the soil, and thereby reduce nitrous oxide emissions.10. Applying nitrogen fertilizer during periods of rapid crop growth can increase nitrogen use efficiency and reduce the amount of nitrogen converted to nitrous oxide40. In addition, precision fertilization technology, such as side-applied nitrogen fertilizer, can accurately control the amount and application location of nitrogen fertilizer according to the actual needs of crops and soil conditions, further reducing nitrous oxide emissions.10。

The characteristics of the soil itself, including soil texture, pH value, organic matter content and aeration, all have an important impact on the production and emission of nitrous oxide. Fine-textured soils (such as loams and clays) are more likely to form anoxic microenvironments due to their strong water retention, thus promoting denitrification and nitrous oxide emissions.35. Soil pH significantly regulates nitrification and denitrification as well as the production and reduction of nitrous oxide by affecting the activity of microorganisms and the reaction rates of enzymes involved in the nitrogen cycle. In general, neutral to slightly alkaline soil conditions may be more favorable for nitrous oxide production14. The soil organic matter content provides a carbon source for denitrifying microorganisms and serves as an electron donor to participate in the reduction process of nitrate, so it may increase the emission of nitrous oxide.14. Good soil aeration is conducive to nitrification, but excessive aeration may inhibit denitrification; conversely, anoxic conditions will promote denitrification.3。

Soil moisture and temperature play key roles in regulating microbial processes involved in nitrous oxide production. High soil moisture (usually expressed as a percentage of field capacity or water-filled pore space (WFPS), typically in excess of 60% WFPS) often limits the diffusion of oxygen in the soil, creating anoxic conditions that promote denitrification and nitrous oxide emissions.18. Increased soil temperatures generally accelerate the metabolic activities of soil microorganisms, including nitrification and denitrification, which may lead to increased nitrous oxide emissions26. In addition, in cold areas, freeze-thaw cycles experienced by soil have also been found to lead to pulsed emissions of nitrous oxide from the soil.50。

The composition and activity of soil microbial communities are critical for the balance between nitrous oxide production and reduction after nitrogen fertilizer application. Different types of bacteria and fungi play different roles in nitrification and denitrification. Their relative abundance and activity in the soil directly affect the production rate and final emission of nitrous oxide.3. In particular, nitrous oxide reductase (nosZ) plays a key role in the process of reducing nitrous oxide to nitrogen, and factors such as soil pH, oxygen content, and carbon sources will affect the activity of this enzyme and the abundance of coding genes.17. In addition, substances such as nitrification inhibitors can effectively reduce nitrous oxide emissions by inhibiting the activity of specific microbial groups.64。

soil properties	Influence mechanism	Trends in nitrous oxide emissions
Soil texture (fine soil such as clay, loam)	Strong water retention, easy to form a hypoxic environment	Increase emissions (promote denitrification)
Soil texture (coarse soil such as sand)	Good ventilation, poor water retention	Reduce emissions (limit denitrification)
pH (neutral to slightly alkaline)	Conducive to nitrification and denitrification	May increase emissions
pH value (too acidic or too alkaline)	May inhibit microbial activity	Impacts are complex and may increase or decrease emissions
Organic matter content	Provide carbon source for denitrifying microorganisms	increase emissions
Ventilation (good)	Conducive to nitrification	May increase emissions
Ventilation (poor/hypoxic)	Promote denitrification	increase emissions

 

In order to effectively reduce nitrous oxide emissions from agricultural activities, a multi-faceted strategy needs to be adopted, covering aspects such as optimizing nitrogen fertilizer management, improving fertilization technology, and adjusting farming methods.

Optimizing nitrogen fertilizer management is the primary measure to reduce nitrous oxide emissions. This includes accurately calculating the amount of nitrogen fertilizer applied based on the actual needs of the crop and avoiding over-fertilization leading to nitrogen accumulation in the soil.10. At the same time, adjusting the application time of nitrogen fertilizer according to the growth stage and nutrient absorption pattern of the crop, and trying to apply fertilizer during the peak demand period of the crop can significantly improve nitrogen use efficiency and reduce nitrogen loss.40. In addition, choosing appropriate fertilization locations and methods, such as applying nitrogen fertilizer near the roots of crops, can also improve nitrogen utilization and reduce the risk of nitrous oxide emissions. Following the 4R principle (Right source, Right rate, Right time, Right place) is an effective way to optimize nitrogen fertilizer management.

The use of slow-release fertilizers and nitrification inhibitors is another important emission reduction strategy. Slow-release fertilizers reduce the short-term occurrence of high concentrations of nitrogen in the soil by slowly releasing nitrogen nutrients, thereby reducing the potential for nitrification and denitrification to produce nitrous oxide.40. Nitrification inhibitors slow down the process of nitrification by inhibiting the activity of microorganisms in the soil that convert ammonium into nitrite, thereby reducing the production of nitrous oxide.64。

The application of precision fertilization technology provides the possibility to manage nitrogen fertilizer more effectively. Using advanced technologies such as remote sensing, global positioning systems (GPS), and soil and crop sensors, it is possible to apply fertilizer on demand and adjust the amount of nitrogen fertilizer according to the specific needs of different areas of the field, thereby improving nitrogen use efficiency and reducing nitrous oxide emissions caused by excessive fertilization.18。

In terms of farming systems, proper crop rotation and cover crop practices can also have an impact on nitrous oxide emissions. Although leguminous cover crops increase nitrogen content in the soil through nitrogen fixation, they may increase the risk of nitrous oxide emissions to a certain extent.10, but through scientific crop rotation and cover crop management, the nitrogen cycle can be optimized and nitrogen loss reduced. For example, avoiding the simultaneous presence of fresh biomass and manure in the soil can reduce nitrous oxide emissions71。

Managing soil properties is also an important aspect of reducing nitrous oxide emissions. By adjusting soil pH, for example by applying lime in acidic soils, the rates of nitrification and denitrification and the production of nitrous oxide can be affected27. Maintaining proper soil moisture is critical to controlling nitrous oxide emissions. Avoiding soils that are too wet or too dry can help reduce emissions.27。

To better understand and manage nitrous oxide emissions from agricultural soils, scientists have developed a variety of measurement and modeling methods. Measurements of nitrous oxide emissions are typically performed in the field and in the laboratory. On-site measurement methods include using a gas chamber method to collect gases released from the soil surface and then analyzing them with instruments such as gas chromatography to determine the concentration and emission rate of nitrous oxide18. Isotope tracing techniques, such as the use of ¹⁵N-labeled nitrogen fertilizers, can help researchers differentiate between different nitrous oxide production pathways, such as nitrification and denitrification4. With the development of technology, new automated measurement systems have also begun to be applied to the monitoring of nitrous oxide, which can achieve higher frequency and longer continuous measurement.80。

In addition to direct measurements, process-based models are also widely used to simulate and predict nitrous oxide emissions under different scenarios. These models describe the nitrogen cycle process in the soil, including nitrification and denitrification, through mathematical equations and take into account the influence of various factors such as climate, soil properties and agricultural management practices. Models such as DAYCENT and Cycles are commonly used tools to simulate the nitrogen cycle and nitrous oxide emissions in agricultural systems.42. These models help assess the potential effects of different management measures on reducing nitrous oxide emissions and predict emissions trends under future climate change scenarios.81. However, due to the complexity of soil systems and the diversity of nitrous oxide production, these models still require continuous improvement and validation to increase the accuracy of their predictions43。

To sum up, the reason why nitrous oxide produced in soil after nitrogen fertilizer application becomes a powerful greenhouse gas is due to its unique production mechanism and excellent greenhouse gas properties. The application of nitrogen fertilizer disrupts the natural nitrogen cycle in the soil, providing sufficient nitrogen sources for microbial processes such as nitrification and denitrification, thereby producing nitrous oxide. As an extremely potent and long-lived greenhouse gas, nitrous oxide has a much higher global warming potential than carbon dioxide, posing a severe challenge to climate change. Its emissions are complexly regulated by various factors such as nitrogen fertilizer type and application method, soil characteristics, soil moisture and temperature, and soil microbial communities.

In the context of mitigating global climate change, it is crucial to address agricultural nitrous oxide emissions. Nitrous oxide emissions can be effectively reduced through a variety of strategies, including optimizing nitrogen management, using new fertilizers and precision farming techniques, adjusting farming systems, and managing soil properties. At the same time, accurately measuring and modeling nitrous oxide emissions is critical to understanding its emission patterns and evaluating the effectiveness of emission reduction measures.

Ongoing research and the adoption of permaculture practices are critical to ensuring global food security while reducing agricultural nitrous oxide emissions. Scientists, farmers and policymakers need to work together to continuously explore and implement more effective emission reduction strategies to cope with the challenges posed by climate change and achieve sustainable development of agriculture.

1. Understanding Global Warming Potentials | US EPA, Retrieved March 31, 2025,https://www.epa.gov/ghgemissions/understanding-global-warming-potentials
2. The Principal Greenhouse Gases and Their Sources, retrieved on March 31, 2025,https://www.neefusa.org/story/climate-change/principal-greenhouse-gases-and-their-sources
3. Nitrous oxide emissions in agricultural soils: A review – ResearchGate, retrieved on March 31, 2025,https://www.researchgate.net/publication/262743686_Nitrous_oxide_emissions_in_agricultural_soils_A_review
4. Nitrogen Fertilization of Lawns Enhanced Soil Nitrous Oxide Emissions by Increasing Autotrophic Nitrification – Frontiers, 檢索日期：3月 31, 2025， https://www.frontiersin.org/journals/environmental-science/articles/10.3389/fenvs.2022.943920/full
5. Nitrous oxide emissions grew 40 percent from 1980 to 2020, accelerating climate change, Retrieved March 31, 2025,https://research.noaa.gov/nitrous-oxide-emissions-grew-40-percent-from-1980-to-2020-accelerating-climate-change/
6. Environmental Impact of Inhaled Anesthetics | Greening the Operating Room and Perioperative Arena – American Society of Anesthesiologists (ASA), 檢索日期：3月 31, 2025， https://www.asahq.org/about-asa/governance-and-committees/asa-committees/environmental-sustainability/greening-the-operating-room/inhaled-anesthetics
7. Ammonium Fertilizer Reduces Nitrous Oxide Emission Compared to Nitrate Fertilizer While Yielding Equally in a Temperate Grassland – MDPI, 檢索日期：3月 31, 2025， https://www.mdpi.com/2077-0472/11/11/1141
8. Global warming potential – Wikipedia, retrieved on March 31, 2025,https://en.wikipedia.org/wiki/Global_warming_potential
9. The Greenhouse Gas No One’s Talking About: Nitrous Oxide on Farms, Explained, Retrieved March 31, 2025,https://civileats.com/2019/09/19/the-greenhouse-gas-no-ones-talking-about-nitrous-oxide-on-farms-explained/
10. Management Strategies to Mitigate N2O Emissions in Agriculture – PMC – PubMed Central, Retrieved on March 31, 2025,https://pmc.ncbi.nlm.nih.gov/articles/PMC8949344/
11. Nitrous oxide emissions in agricultural soils: a review – SciELO, retrieved on March 31, 2025,https://www.scielo.br/j/pat/a/yyfWQ9zyWJVdknyBfYFP3wD/?lang=en
12. Nitrous Oxide and California Agriculture – UC ANR, Retrieved March 31, 2025,https://ucanr.edu/site/solution-center-nutrient-management/nitrous-oxide-and-california-agriculture
13. Impact of agriculture on N2O emissions: A review* – Biblioteka Nauki, Retrieved March 31, 2025,https://bibliotekanauki.pl/articles/53645365.pdf
14. Nitrous oxide (N2O) emission characteristics of farmland (rice, wheat, and maize) based on different fertilization strategies – PMC, 檢索日期：3月 31, 2025， https://pmc.ncbi.nlm.nih.gov/articles/PMC11230557/
15. Nitrous Oxide Emissions from Soil | Oklahoma State University, Retrieved March 31, 2025,https://extension.okstate.edu/fact-sheets/nitrous-oxide-emissions-from-soil.html
16. Nitrous Oxide Emissions from Soil – Oklahoma State University Extension, Retrieved March 31, 2025,https://extension.okstate.edu/fact-sheets/print-publications/pss/nitrous-oxide-emissions-from-soil-pss-2269.pdf
17. Interactions of fertilisation and crop productivity in soil … – SOIL, retrieved on March 31, 2025,https://soil.copernicus.org/articles/11/1/2025/
18. Nitrous oxide emissions from soils: how well do we understand the…, Retrieved March 31, 2025,https://pmc.ncbi.nlm.nih.gov/articles/PMC3682742/
19. Nitrification Is a Primary Driver of Nitrous Oxide … – Frontiers, Retrieved March 31, 2025,https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2016.01373/full
20. Nitrous oxide production from granular nitrogen fertilizers applied to a silt loam soil, Retrieval date: March 31, 2025,https://cdnsciencepub.com/doi/10.4141/S02-062
21. pmc.ncbi.nlm.nih.gov, retrieved on March 31, 2025,https://pmc.ncbi.nlm.nih.gov/articles/PMC11052285/#:~:text=The%20application%20of%20urea%20in,have%20not%20been%20thoroughly%20investigated.
22. Urea Fertilization Significantly Promotes Nitrous Oxide Emissions …, Retrieved March 31, 2025,https://pmc.ncbi.nlm.nih.gov/articles/PMC11052285/
23. Full article: Nitrous oxide emission factors for fertiliser ammonium …, Retrieval date: March 31, 2025,https://www.tandfonline.com/doi/full/10.1080/00288233.2023.2277916
24. www.tandfonline.com, retrieved on March 31, 2025,https://www.tandfonline.com/doi/full/10.1080/00288233.2023.2277916#:~:text=Research%20conducted%20by%20Rahman%20et,through%20denitrification%20in%20the%20soil.
25. Nitrogen use efficiency and nitrous oxide emissions from five UK fertilised grasslands – PMC, Retrieved March 31, 2025,https://pmc.ncbi.nlm.nih.gov/articles/PMC6383039/
26. Full article: Interactive effects of ammonium application rates and temperature on nitrous oxide emission from tropical agricultural soil, 檢索日期：3月 31, 2025， https://www.tandfonline.com/doi/full/10.1080/00380768.2018.1517280
27. Factors That Influence Nitrous Oxide Emissions from Agricultural Soils as Well as Their Representation in Simulation Models: A Review – MDPI, 檢索日期：3月 31, 2025， https://www.mdpi.com/2073-4395/11/4/770
28. pmc.ncbi.nlm.nih.gov, retrieved on March 31, 2025,https://pmc.ncbi.nlm.nih.gov/articles/PMC2838029/#:~:text=Overall%2C%20our%20results%20indicate%20that,2O%20production%20were%20observed.
29. Intermediate soil acidification induces highest nitrous oxide …, Retrieved: March 31, 2025,https://www.osti.gov/pages/biblio/2470913
30. Effects of Biochar Amendment on N2O Emissions from Soils with…, Retrieval date: March 31, 2025,https://www.mdpi.com/2073-4433/15/1/68
31. Insights into the Effect of Soil pH on N2O and N2 Emissions and Denitrifier Community Size and Activity – PubMed Central, 檢索日期：3月 31, 2025， https://pmc.ncbi.nlm.nih.gov/articles/PMC2838029/
32. Intermediate soil acidification induces highest nitrous oxide emissions – PubMed, retrieved on March 31, 2025,https://pubmed.ncbi.nlm.nih.gov/38538640/
33. Effect of soil pH on nitrous oxide emissions from agricultural soils – Thünen-Institut, Retrieved March 31, 2025,https://www.thuenen.de/en/cross-institutional-projects/effect-of-soil-ph-on-nitrous-oxide-emissions-from-agricultural-soils
34. A Longitudinal Study of the Microbial Basis of Nitrous … – Frontiers, retrieved on March 31, 2025,https://www.frontiersin.org/journals/agronomy/articles/10.3389/fagro.2022.833338/full
35. Soil Nitrous Oxide Emissions Following Crop Residues Management in Corn-Wheat Rotation Under Conventional and No-Tillage Systems – Morad Mirzaei, Manouchehr Gorji Anari, Arezoo Taghizadeh-Toosi, Mohammad Zaman, Nermina Saronjic, Safwan Mohammed, Szilard Szabo, Andres Caballero-Calvo, 2022 – Sage Journals, March 31, 2025, https://journals.sagepub.com/doi/10.1177/11786221221128789
36. Nitrous Oxide Emissions | US EPA, Retrieved March 31, 2025,https://www.epa.gov/ghgemissions/nitrous-oxide-emissions
37. (PDF) Effect of split application of fertilizer nitrogen on N2O …, Retrieval date: March 31, 2025,https://www.researchgate.net/publication/261287161_Effect_of_split_application_of_fertilizer_nitrogen_on_N2O_emissions_from_potatoes
38. Effects of Split Application of Urea on Greenhouse Gas … – Frontiers, Retrieved March 31, 2025,https://www.frontiersin.org/journals/environmental-science/articles/10.3389/fenvs.2021.798383/full
39. Effect of split application of fertilizer nitrogen on N 2 O emissions from potatoes, Retrieval date: March 31, 2025,https://cdnsciencepub.com/doi/10.4141/CJSS06007
40. Following Nutrient Management Guidelines can Help to Reduce Nitrous Oxide Emissions, Retrieved: March 31, 2025,https://www.climatehubs.usda.gov/hubs/northeast/topic/following-nutrient-management-guidelines-can-help-reduce-nitrous-oxide
41. Soil texture, fertilization, cover crop species and management affect nitrous oxide emissions from no-till cropland – PubMed, 檢索日期：3月 31, 2025， https://pubmed.ncbi.nlm.nih.gov/38215843/
42. (PDF) Simulated Effects of Soil Texture on Nitrous Oxide Emission …, Retrieved March 31, 2025,https://www.researchgate.net/publication/307946870_Simulated_Effects_of_Soil_Texture_on_Nitrous_Oxide_Emission_Factors_from_Corn_and_Soybean_Agroecosystems_in_Wisconsin
43. The importance of management information and soil moisture representation for simulating tillage effects on N2O emissions in LPJmL5.0-tillage – GMD, 檢索日期：3月 31, 2025， https://gmd.copernicus.org/articles/13/3905/
44. Soil N2 O emissions from specialty crop systems: A global estimation and meta-analysis, Retrieval date: March 31, 2025,https://pubmed.ncbi.nlm.nih.gov/38469991/
45. Full article: Nitrous oxide emission derived from soil organic matter decomposition from tropical agricultural peat soil in central Kalimantan, Indonesia – Taylor & Francis Online, 檢索日期：3月 31, 2025， https://www.tandfonline.com/doi/full/10.1080/00380768.2011.587203
46. Modeling nitrous oxide emissions from agricultural soil incubation experiments using CoupModel – BG, Retrieved on March 31, 2025,https://bg.copernicus.org/articles/19/4811/2022/
47. Organic matter contributions to nitrous oxide emissions following nitrate addition are not proportional to substrate-induced soil carbon priming – PubMed, 檢索日期：3月 31, 2025， https://pubmed.ncbi.nlm.nih.gov/36030860/
48. Full article: Effects of soil aggregate size, moisture content and …, Retrieval date: March 31, 2025,https://www.tandfonline.com/doi/full/10.1080/00380768.2011.604767
49. Impacts of Climate Change and Agricultural Practices on Nitrogen…, Retrieved March 31, 2025,https://www.mdpi.com/2077-0472/14/2/240
50. Non seasongrowing soil nitrous oxide emissions as influenced by …, Retrieved: March 31, 2025,https://cdnsciencepub.com/doi/10.1139/cjss-2023-0017
51. Effects of Soil Temperature, Flooding, and Organic Matter Addition on N2O Emissions from a Soil of Hongze Lake Wetland, China – PMC, Search date: March 31, 2025,https://pmc.ncbi.nlm.nih.gov/articles/PMC4123519/
52. Effects of soil temperature and moisture on methane uptake and nitrous oxide emissions across three different ecosystem types – BG, 檢索日期：3月 31, 2025， https://bg.copernicus.org/articles/10/3205/2013/bg-10-3205-2013.pdf
53. Land Use, Temperature, and Nitrogen Affect Nitrous Oxide Emissions in Amazonian Soils, Retrieved March 31, 2025,https://www.mdpi.com/2073-4395/12/7/1608
54. Soil Moisture but Not Warming Dominates Nitrous Oxide … – Frontiers, Retrieved March 31, 2025,https://www.frontiersin.org/journals/ecology-and-evolution/articles/10.3389/fevo.2021.676027/full
55. Responses of Nitrous Oxide Emissions and Bacterial Communities to Experimental Freeze–Thaw Cycles in Contrasting Soil Types – MDPI, 檢索日期：3月 31, 2025， https://www.mdpi.com/2076-2607/11/3/593
56. Physicochemical perturbation increases nitrous oxide … – BG, Retrieved March 31, 2025,https://bg.copernicus.org/articles/21/4837/2024/
57. Aerobic denitrification as an N2O source from microbial communities …, Retrieved: March 31, 2025,https://academic.oup.com/ismej/article/18/1/wrae116/7697971
58. Diversity and Activity of Soil N2O-Reducing Bacteria Shaped by Urbanization | Environmental Science & Technology – ACS Publications, 檢索日期：3月 31, 2025， https://pubs.acs.org/doi/10.1021/acs.est.4c01750
59. Denitrification contributes to N2O emission in paddy soils – Frontiers, Retrieved March 31, 2025,https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2023.1218207/full
60. Ecological and physiological implications of nitrogen oxide reduction pathways on greenhouse gas emissions in agroecosystems – Oxford Academic, 檢索日期：3月 31, 2025， https://academic.oup.com/femsec/article/95/6/fiz066/5488431
61. Role of Microorganisms in Emission of Nitrous Oxide and Methane in Pulse Cultivated Soil Under Laboratory Incubation Condition, 檢索日期：3月 31, 2025， https://pmc.ncbi.nlm.nih.gov/articles/PMC3587505/
62. New method could significantly reduce agricultural greenhouse gas emissions | IIASA, Retrieved March 31, 2025,https://iiasa.ac.at/news/may-2024/new-method-could-significantly-reduce-agricultural-greenhouse-gas-emissions
63. Nitrous oxide emissions from soils: how well do we understand the processes and their controls? | Philosophical Transactions of the Royal Society B: Biological Sciences – Journals, 檢索日期：3月 31, 2025， https://royalsocietypublishing.org/doi/10.1098/rstb.2013.0122
64. www.piccc.org.au, Retrieved March 31, 2025,https://www.piccc.org.au/research/project/269#:~:text=Across%20the%20laboratory%20studies%2C%20nitrifi,both%20slightly%20reduced%20inhibitor%20efficacy.
65. www.climatexchange.org.uk, retrieved March 31, 2025,https://www.climatexchange.org.uk/wp-content/uploads/2023/09/iq28-2019-evidence-review-of-the-efficacy-of-nitrification-and-urease-inhibitors.pdf
66. Nitrous Oxide Production and Mitigation Through Nitrification Inhibitors in Agricultural Soils: A Mechanistic Understanding and Comprehensive Evaluation of Influencing Factors – MDPI, 檢索日期：3月 31, 2025， https://www.mdpi.com/2504-3129/6/1/14
67. A meta-analysis to examine whether nitrification inhibitors work through selectively inhibiting ammonia-oxidizing bacteria – Frontiers, 檢索日期：3月 31, 2025， https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2022.962146/full
68. Nitrification inhibitors: performance drivers | Primary Industries Climate Challenges Centre, Retrieved March 31, 2025,https://piccc.org.au/research/project/269.html
69. Inhibiting nitrous oxide emissions – Science Learning Hub, retrieved on March 31, 2025,https://www.sciencelearn.org.nz/resources/922-inhibiting-nitrous-oxide-emissions
70. Meta‐analysis of yield and nitrous oxide outcomes for nitrogen management in agriculture, Retrieval date: March 31, 2025,https://pmc.ncbi.nlm.nih.gov/articles/PMC8252581/
71. Developing climate-friendly farming practices to reduce nitrous …, Retrieved: March 31, 2025,https://landgrantimpacts.org/developing-climate-friendly-farming-practices-to-reduce-nitrous-oxide-emissions/
72. www.climatehubs.usda.gov, retrieved March 31, 2025,https://www.climatehubs.usda.gov/hubs/northeast/topic/following-nutrient-management-guidelines-can-help-reduce-nitrous-oxide#:~:text=The%20use%20of%20enhanced%20efficiency,plants%20have%20higher%20N%20demand.
73. Effect of controlled-release fertilizer on nitrous oxide emission from a…, Retrieval date: March 31, 2025,https://www.researchgate.net/publication/257564031_Effect_of_controlled-release_fertilizer_on_nitrous_oxide_emission_from_a_winter_wheat_field
74. Enhanced Efficiency Fertilizers: Effect on Nitrous Oxide Emissions in Iowa – University of Nebraska–Lincoln, Retrieved March 31, 2025,https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=2358&context=usdaarsfacpub
75. Effects of coated slow-release fertilizers on nitrous oxide emission from winter wheat field in a cool-temperate region, 檢索日期：3月 31, 2025， https://www.tandfonline.com/doi/pdf/10.1080/00380768.2022.2038521
76. Measures to Reduce Emissions in Agricultural Production – Nebraska Department of Environment and Energy, Retrieved March 31, 2025,https://dee.nebraska.gov/sites/default/files/publications/Ag%20Registry%20and%20Grants%20Program.pdf
77. Food has a climate problem: Nitrous oxide emissions are …, Retrieved: March 31, 2025,https://www.theinvadingsea.com/2024/07/31/nitrogen-fertilizer-climate-change-farming-food-nitrous-oxide-emissions-precision-agriculture/
78. Agriculture emits a ‘forgotten greenhouse gas.’ Scientists are looking for solutions in the soil, 檢索日期：3月 31, 2025， https://www.pbs.org/newshour/science/agriculture-emits-a-forgotten-greenhouse-gas-scientists-are-looking-for-solutions-in-the-soil
79. Climate-smart ag strategies may cut nitrous oxide emissions from corn production, Retrieved: March 31, 2025,https://www.psu.edu/news/research/story/climate-smart-ag-strategies-may-cut-nitrous-oxide-emissions-corn-production
80. Soil study shows why nitrous oxide emissions should factor into …, Retrieved March 31, 2025,https://www.news.iastate.edu/news/soil-study-shows-why-nitrous-oxide-emissions-should-factor-climate-change-mitigation
81. Process-based modeling of soil nitrous oxide emissions from United States corn fields under different management and climate scenarios coupled with evaluation using regional estimates – Frontiers, 檢索日期：3月 31, 2025， https://www.frontiersin.org/journals/environmental-science/articles/10.3389/fenvs.2022.971261/full
82. Modeling the Nitrogen Balance and Nitrous Oxide Emission of Organic Grain and Forage Production Systems – J. Jeffrey and Ann Marie Fox Graduate School at Penn State, 檢索日期：3月 31, 2025， https://gradschool.psu.edu/student-support/professional-development/graduate-exhibition/graduate-exhibition-listings/modeling-the-nitrogen-balance-and-nitrous-oxide-emission-of-organic-grain-and-forage-production-systems
83. A Review of the Main Process-Based Approaches for Modeling N2O…, Retrieved on March 31, 2025,https://www.mdpi.com/2311-7524/10/1/98
84. First-Ever Conceptual Model Explains Variations in Farm N2O Emissions | ILLINOIS, Retrieved March 31, 2025,https://sustainability.illinois.edu/ascs-new-cannon-model-explains-variations-in-agricultural-n2o-emissions/
85. Computer models show how crop production increases soil nitrous oxide emissions, Retrieved March 31, 2025,https://www.news.iastate.edu/news/computer-models-show-how-crop-production-increases-soil-nitrous-oxide-emissions
86. Nitrous oxide emission modeling and measurements – Department of Plant Science, Retrieval date: March 31, 2025,https://plantscience.psu.edu/research/labs/kemanian/research/research-topics/nitrous-oxide-emission-modeling-and-measurements
87.