Managing urban development could halve nitrogen pollution in China.

Area of Science:

• Environmental Science
• Urban Planning
• Sustainable Development

Background:

• Nitrogen pollution poses a significant challenge to achieving Sustainable Development Goals (SDGs).
• Reducing nitrogen pollution from diverse sources requires innovative strategies.
• Urbanization presents a complex but potentially effective pathway for pollution mitigation.

Purpose of the Study:

• To investigate the potential of managed urban development in China to reduce reactive nitrogen (Nr) pollution by 2050.
• To quantify the impact of urbanization on atmospheric emissions (NH3, NOx, N2O) and water pollution.
• To assess the economic feasibility and benefits of implementing such a strategy.

Main Methods:

• Modeling the effects of rural-urban migration on point-source and non-point-source pollution.
• Analyzing the impact of land consolidation and livestock relocation on nitrogen pollution.
• Calculating the costs and benefits of investments in waste treatment and agricultural practices.

Main Results:

• Reactive nitrogen pollution could be reduced by approximately 50% by 2050 through managed urban development.
• Atmospheric emissions of NH3, NOx, and N2O are projected to decrease by 44%, 30%, and 33%, respectively.
• Nitrogen runoff to water bodies is estimated to decrease by 53%, with an overall economic benefit of US$245 billion from a US$61 billion investment.

Conclusions:

• Managed urbanization in China offers a feasible and cost-effective approach to significantly reduce nitrogen pollution.
• This strategy contributes to multiple SDGs, including poverty reduction, food security, clean water, responsible consumption, and climate action.
• Urban development can simultaneously address air and water quality improvements by optimizing land use and agricultural practices.