Ecology and Environmental Aspects of Nitrogen in Agriculture

**3**

**Chapter 1**

**Abstract**

**1. Introduction**

mole basis).

in Agriculture

Mitigation of Climate Change

Soil is one of the important sources of nitrous oxide (N2O), which is generally producing through soil microbial processes, such as nitrification and denitrification. Agricultural soils receive chemical and organic fertilizers to maintain or increase crop yield and soil fertility, but several factors are influencing N2O emissions, such as types and conditions of soil and fertilizer, and rate, form, and timing of application. Mitigation of N2O is a challenging topic for future earth by using inhibitors, controlled-release fertilizers, and other amendments, but the cost and

Global warming is significant and the impact of human activities is no doubt, such as mining of fossil fuels and deforestation, over-grazing, and constant increase of nitrogen fertilizer, resulting in atmospheric concentrations of CO2, methane (CH4) and nitrous oxide (N2O) keep increasing, respectively, as indicated by Intergovernmental Panel on Climate Change (**IPCC**), under the United National Framework Convention on Climate Change (**UNFCCC**) (**Figure 1**, [1]). CH4 and N2O are the main Short-Lived Climate Forcers (**SLCPs**) because these participate in air pollution chemistry (ozone production, the oxidizing capacity of the atmosphere) and have very high Global Warming Potential (**GWP**) to compare with CO2 = 1 as CH4 GWP = ~28; N2O GWP = ~298 (100 yr integration on per

The Japanese government declared in 2020 that the year 2050 is the target of "Carbon Neutral Society", like other OECD countries. To achieve this target, we should reduce greenhouse gas emissions, not only CO2 but also CH4 and N2O, both

Soil is one of the important sources of N2O, which is generally producing through soil microbial processes, such as nitrification and denitrification. Agricultural soils receive chemical and organic fertilizers to maintain or increase crop yield and soil fertility. However, excess amount of chemical N fertilizer application may cause eutrophication and ground water pollution in the hydrosphere. Moreover, many factors are also influencing N2O emission in the atmosphere, such as types and conditions of soil and fertilizer, and rate, form, and timing of application. Mitigation of N2O emission to the atmosphere is a challenging topic in

strongly related to food production and agriculture sectors.

by Nitrogen Managements

*Kazuyuki Inubushi and Miwa Yashima*

side effects should be considered for feasibility.

**Keywords:** N2O, nitrification, denitrification, mitigation, soil type

#### **Chapter 1**
