Pilot practical exploration of coordinated pollution reduction and carbon reduction based on ecological environment zoning control: a case study in Zengcheng District, Guangzhou City

Carrying out a pilot project of coordinated pollution reduction and carbon reduction based on ecological environment zoning control (EEZC) is an important measure to integrate the requirements of carbon peak and carbon neutrality into EEZC system, which is of great significance to promoting green and low-carbon development. Taking Zengcheng District, Guangzhou City as an example and based on the technical methods and achievements of EEZC, an inventory of air pollutants and CO₂ emissions was constructed based on GIS spatial statistical methods. The generation and emission coefficient method was used to calculate the reduction of air pollutants and CO₂ emissions, and the relative degree assessment method of the synergistic effect of pollution reduction and carbon reduction was used to evaluate the synergistic effect of the measures. In addition, a localized pollution reduction and carbon reduction measures library was constructed, and the CMAQ model was used to evaluate the benefits of air quality improvement by optimizing the measures. Finally, corresponding policy recommendations were put forward. The result showed that: (1) The key areas for coordinated control of pollution reduction and carbon reduction were located in the southern part of Zengcheng, and the key industries included cogeneration, automobile manufacturing, automobile parts and accessories manufacturing, and motorcycle manufacturing. (2) According to the evaluation of the coordinated emission reduction and the synergy of the measures, 12 localized pollution reduction and carbon reduction measures were constructed. Among these measures, industrial green and low-carbon microgrid construction, coating process upgrading, low-nitrogen staged combustion transformation, and ultra-low emission transformation showed good comprehensive emission reduction benefits. (3) Based on the GIS spatial mapping identification method, 5 EEZC units to be optimized were identified, including 3 key and 2 general control units. (4) The CMAQ model was used to compare and analyze the inventories before and after optimization, and the direct emission reduction and indirect air quality improvement benefits after the inclusion of coordinated control measures for pollution reduction and carbon reduction were evaluated. The emission reduction of SO₂, NO_x, PM and VOCs was 76, 288, 58, and 139 t, respectively, and the emission reduction of CO₂ was 530 000 t. The concentration of PM_2.5, SO₂ and NO₂ decreased by 0.254, 1.844 and 2.893 μg/m³, respectively. This study can provide a reference for the next step of EEZC and promote coordinated control of pollution reduction and carbon reduction.