科学研究

Jianwei Xing is an assistant professor of economics at National School of Development at Peking University. He graduated from Cornell University with a doctorate degree in applied economics in 2018. His research interests are environmental economics and empirical industrial organization. He is particularly interested in research topics related to electric vehicles, industrial policy, the economic consequences of environmental enhancement, and digital economy. His recent research has appeared in Journal of Environmental Economics and Management, Journal of the Association of Environmental and Resource Economists, Journal of Public Economics, and American Economic Journal: Macroeconomics.

We evaluate urban forests’ health values and risks through a massive afforestation program in the city of Beijing, which planted over a third of a million acres of greenery across the city over a decade. We conduct a remote-sensing audit of the program, finding that it contributes to a substantial greening up of the city. This causes significant downwind air quality improvement, reducing average PM2.5 concentration at city population hubs by 4.2 percent. Rapid vegetation growth, however, led to a 7.4 percent increase in pollen exposure. Analysis of medical claims data shows that increased aeroallergens triggered emergency room visits, mirroring pollution effects though much less severe. Monetized net health benefits of the program amount to 1.5 percent of the city’s GDP, on par with the cost of the program. We find an overall housing price appreciation near the afforested areas, although this effect does not align closely with urban forests’ downwind pollution impact gradient, and is thus more likely driven by the capitalization of localized amenities.