Management Strategies to Mitigate N2O Emissions in Agriculture

Abstract

The concentration of greenhouse gases (GHGs) in the atmosphere has been increasing since the beginning of the industrial revolution. Nitrous oxide (N2O) is one of the mightiest GHGs, and agriculture is one of the main sources of N2O emissions. In this paper, we reviewed the mechanisms triggering N2O emissions and the role of agricultural practices in their mitigation. The amount of N2O produced from the soil through the combined processes of nitrification and denitrification is profoundly influenced by temperature, moisture, carbon, nitrogen and oxygen contents. These factors can be manipulated to a significant extent through field management practices, influencing N2O emission. The relationships between N2O occurrence and factors regulating it are an important premise for devising mitigation strategies. Here, we evaluated various options in the literature and found that N2O emissions can be effectively reduced by intervening on time and through the method of N supply (30–40%, with peaks up to 80%), tillage and irrigation practices (both in non-univocal way), use of amendments, such as biochar and lime (up to 80%), use of slow-release fertilizers and/or nitrification inhibitors (up to 50%), plant treatment with arbuscular mycorrhizal fungi (up to 75%), appropriate crop rotations and schemes (up to 50%), and integrated nutrient management (in a non-univocal way). In conclusion, acting on N supply (fertilizer type, dose, time, method, etc.) is the most straightforward way to achieve significant N2O reductions without compromising crop yields. However, tuning the rest of crop management (tillage, irrigation, rotation, etc.) to principles of good agricultural practices is also advisable, as it can fetch significant N2O abatement vs. the risk of unexpected rise, which can be incurred by unwary management.

Partial Exchange of Mineral N Fertilizer for Common Bean Plants by Organic N Fertilizer in the Presence of Salicylic Acid as Foliar Application

“…Chemical fertilizers are costly and have negative environmental consequences (Adediran et al 2004;Chandini et al 2019). Furthermore, the use of nitrogen-rich mineral fertilizers to maintain crop output is responsible for 60% of global anthropogenic N2O emissions (Meng and Ding 2005;Ma et al 2021;Hassan et al 2022); hence, organic matter (compost) should be used instead of chemical fertilizers (Murphy 2014). Organic fertilizers effectively improve soil properties and increase root growth and soil microbe activity (Sanwal et al 2007).…”

Recent trends in nitrogen cycle and eco-efficient nitrogen management strategies in aerobic rice system

“…Leaching of NO 3 – -N from rice soils is also a major source of pollution spread in groundwater reserves, where NO 3 – entering the soil surface via leaching or runoff may stimulate eutrophication ( Wick et al, 2012 ). N oxides emitted during nitrification or denitrification pathways are major GHGs that compromise the availability of a sustainable and healthy environment ( Subbarao et al, 2013 ; Hu et al, 2017 ; Groenveld et al, 2020 ; Hassan et al, 2022 ). Various forms of reactive oxygen can pose impacts on environmental sustainability if immobilized or denitrified in previous N 2 forms ( Pan et al, 2022 ).…”

Dairy Slurry Application to Stubble-Covered Soil: A Study on Sustainable Alternatives to Minimize Gaseous Emissions

“…The temperature was recorded at each sampling point. Gas measurements were carried out on days 2,6,9,15,17,21,24,29,34,44,52,58,63,73,77,85, 99 and 108 after the start of the experiment.…”

“…Emissions of reactive N into the atmosphere threaten human health and decrease fertilizer value by reducing the N available for crop nutrition [12,15,16]. Thus, acting on N fertilizer (e.g., source, application method, time and treatment) is the most practical way to reduce N gas emissions [12,17].…”