Responses of nitrogen and sulfur deposition to NH3 emission control in the Yangtze River Delta, China. (1st September 2022)

• Record Type: Journal Article
• Authors: Dong, Zhaoxin; Xing, Jia; Wang, Shuxiao; Ding, Dian; Ge, Xiaodong; Zheng, Haotian; Jiang, Yueqi; An, Jingyu; Huang, Cheng; Duan, Lei; Hao, Jiming
• Is Part Of: Environmental pollution. Volume 308(2022)
• Publication Date: 2022-09-01
• Subjects: NH3 emission control -- Sulfur deposition -- Nitrogen deposition -- Response surface model -- Synergistic effect; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2022.119646
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: NH3 emission control has proven to be of great importance in reducing PM2.5 concentrations in China, while how it affects nitrogen/sulfur (N/S) deposition is still unclear. This study expanded the response surface model method to quantify the responses of N/S deposition to the emission control of precursors (NOx, SO2, NH3, VOCs and primary PM2.5 ) in the Yangtze River Delta, China. NH3 control was found to have higher efficiency in reducing N/S deposition than NOx and SO2 alone. The reduced N deposition response to NH3 emission control was higher in the northern part of the YRD region, whereas oxidized N deposition decreased sharply in the region with a low N critical load. Synergetic effect was found in reducing N deposition when we controlled the NH3 and NOx emissions simultaneously. Compared with the sum effect of individual NH3 and NOx emission control, the extra benefits from the synergy controls accounted for 4.4% (1.23 kg N·ha −1 ·yr −1 ) of the total N deposition, of which 81% came from the oxidized N deposition. The YRD region could receive the largest synergetic effect with a 1:1 ratio of NOx :NH3 emission reduction. The NH3 emission control increases the dry deposition of acid substances and worsens acid rain though it reduces the wet S/oxidized N deposition. These findings highlight the effectiveness of NH3 emission control and suggest a multi-pollutant control strategy for reducing N/S deposition. The response surface model method for deposition also provides a reference for other regions in China and other countries. Graphical abstract: Image 1 Highlights: NH3 control has higher efficiency in reducing reduced N deposition. Synergic NOx /NH3 control reduce 4.4% more N deposition than the sum of individual control. 1:1 ratio of NOx :NH3 emission reduction could lead to the largest synergetic effect. NH3 emission control worsens acid rain though it decreases wet S deposition.