![]() It must strive to build a resource conservative and environmentally friendly society and enhance the national capacity to mitigate GHG China's GHG emissions in relation to N fertilizer useĬhina's total GHG emissions were 4060, 61 Tg CO 2eq in 1994, 20, respectively. China attaches great importance to the issue of climate change. Increased global GHG emission is regarded as one of most important drivers for global climate change. That is why national fertilizer N use has increased by a factor of three, from about 10 Tg N yr −1 in 1980 to 33 Tg N yr −1 Climate change and its impact in ChinaĬlimate change has been a global issue and has impacted food security and human health in many regions, according to the United Nations Framework Convention on Climate Change (UNFCCC). Under the pressure of the rapidly increasing population, the national agricultural policy has focused largely on how to promote crop production by increasing N fertilizer application together with other agricultural chemicals. The majority of anthropogenic NH 3 is emitted from N fertilizers and animal excreta [11 Nitrogen fertilizer use and its environmental damage in ChinaĪlthough the history of N fertilizer application in China stretches back more than 100 years, widespread use of N fertilizer has occurred only since 1980. The rapid increases in emissions of both Nr species are largely related to intensive agricultural and industrial activities. ![]() NH 3 emissions (13.7 Tg N yr −1) have doubled and NO x emissions (6.0 Tg N yr −1) have quadrupled between 19. Emissions of NH 3 and NO x have increased continuously since 1980. Section snippets Atmospheric Nr emissions and pollution in ChinaĪ number of studies have been conducted to evaluate reduced and oxidized N emissions in China. Therefore the relationship between N cycling, GHG emissions and climate change must be taken more seriously in China as well as in other rapidly developing economies. In addition, N cycling may affect carbon (C) sequestration in terrestrial ecosystems and this must be taken into account in predicting CO 2 uptake in the future. As a consequence, more N 2O and other GHG gases may be emitted from both croplands and non-arable soils and may further accelerate the rate of climate change. Climate change, especially climate warming, may accelerate N cycling in terrestrial ecosystems. Figure 1 is a conceptual diagram which links N fertilizer use, agricultural production, GHG emissions and climate change together. The impact of N fertilizer use on crop production, GHG emissions and climate change will become increasingly important because of rapidly increasing fertilizer N consumption since 1980. A three-fold increase in N fertilizer application in agriculture has contributed to a near 70% increase in grain production in China since 1980 and the country has also become one of the largest greenhouse gas (GHG) emitters in the world. Therefore N use and climate change are two very important issues in China because they are closely related to food security. It is well known that nitrogen (N) plays a key role in air pollution (via NO x and NH 3 emissions, and indirectly on O 3) and climate change (through N 2O emissions and aerosols, and indirectly through its effect on CO 2, CH 4 and O 3 emissions) and also in food production and biodiversity loss. These N feedbacks should be taken into account when considering mitigation of GHG emissions. This climate change has threatened national cereal production and may accelerate N cycling (i.e., N 2O emissions) in croplands and non-arable soils. China has also witnessed detectable climate warming, fluctuations in precipitation and other extreme weather conditions over the last 30 years. ![]() Strategies to reduce N fertilizer loss and GHG emissions are mentioned briefly. The GHG emissions from N fertilizer production and transport (274 Tg CO 2eq yr −1) and use for crop (403 Tg CO 2eq yr −1) application occupied a major part of total agricultural emissions in China, in spite of small carbon (C) sequestration in croplands (28–37 Tg CO 2eq yr −1) induced by N fertilizer. ![]() As a consequence, gaseous Nr emissions including NH 3, NO x and N 2O have increased substantially since 1980, directly or indirectly contributing to the greenhouse gas (GHG) balance and climate change. Motor vehicles, power plants and industrial facilities are consuming large amounts of fossil fuels. Overuse of nitrogen (N) fertilizer has occurred widely in Chinese agriculture. In order to meet the increasing demand for food in China, increasingly more reactive nitrogen (Nr) species have been synthesized by the Haber–Bosch process. China is facing great challenges in both food security and environmental sustainability against the background of global climate change.
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