A Declining Trend in China’s Future Cropland-N₂O Emissions Due to Reduced Cropland Area

Abstract

Croplands are the largest anthropogenic source of nitrous oxide (N2O), a powerful greenhouse gas that contributes to the growing atmospheric N2O burden. However, few studies provide a comprehensive depiction of future cropland-N2O emissions on a national scale due to a lack of accurate cropland prediction data. Herein, we present a newly developed distributed land-use change prediction model for the high-precision prediction of national-scale land-use change. The high-precision land-use data provide an opportunity to elucidate how the changes in cropland area will affect the magnitude and spatial distribution of N2O emissions from China’s croplands during 2020–2070. The results showed a declining trend in China’s total cropland-N2O emissions from 0.44 ± 0.03 Tg N/year in 2020 to 0.39 ± 0.07 Tg N/year in 2070, consistent with a cropland area reduction from (1.78 ± 0.02) × 108 ha to (1.40 ± 0.15) × 108 ha. However, approximately 31% of all calculated cities in China would emit more than the present level. Furthermore, different land use and climate change scenarios would have important impacts on cropland-N2O emissions. The Grain for Green Plan implemented in China would effectively control emissions by approximately 12%.

Boosting N2O Decomposition by Fabricating the Cs–O–Co Structure over Co3O4 with Single-Layer Atoms of Cs

“…Nitrous oxide (N 2 O), as a major greenhouse gas, received considerable attention due to the high global warming potential and ozone depletion. − The global annual anthropogenic N 2 O emissions have reached 7 tera-grams, where the increasing emissions from catalyst usage in vehicles and the chemical production of adipic acids provide substantial contributions besides agriculture sources. − To achieve the ambitious goal of carbon neutrality, the European Parliament applied the N 2 O emission standard for nitric acid plants to 2.5 kg/t HNO 3 . Tier 3 in the USA has required the vehicles to meet the EPA N 2 O tailpipe standard of 0.01 g/mi in 2017 .…”

Warming and cooling effects of local climate zones on urban thermal environment

“…With the continued progress of urbanization, artificial structures such as roads and houses are increasing in number and substantially changing the surface form (1). Extensive urban growth in the past has created a particular burden on the environment, thereby affecting the balance of urban climate regulation and causing numerous problems such as the heat island effect and air pollution (2)(3)(4).…”

“…With the continued progress of urbanization, artificial structures such as roads and houses are increasing in number and substantially changing the surface form ( 1 ). Extensive urban growth in the past has created a particular burden on the environment, thereby affecting the balance of urban climate regulation and causing numerous problems such as the heat island effect and air pollution ( 2 – 4 ). Global heat exposure has risen dramatically in recent years, thus increasing the risk of extreme heat and the frequency of deaths; heat-related excess deaths are projected to rise by 2.4% in 2030 and by 5.5% in 2090 ( 5 – 9 ).…”

“…The ranking of the contribution of different LCZs to LST was compared by a standardized coefficient. This study aimed to solve two problems: ( 1 ) Creating a new method to measure the combined impact between LCZs, and ( 2 ) revealing the thermal characteristics of LCZ under combined effects. We used the area within the fourth ring road of Shenyang as a case study, but this method can be extended to other areas.…”

Devoting Attention to China’s Burgeoning Industrial N2O Emissions

“…N 2 O emissions from wastewater are positively proportional to the reactive nitrogen flow in the wastewater. Since China imposed regulations to reduce the usage of chemical fertilizers and decreased the size of cropland areas, China’s agricultural and indirect N 2 O emissions are projected to decline over the foreseeable future. In addition, the Chinese population is forecast to decline around 2030, further reducing N 2 O emissions from wastewater in the years to come.…”