Prediction of ozone pollution impacted by vegetation planning in the Pearl River Delta, China

Abstract

Controlling severe ozone (O3) pollution has become an urgent issue for addressing air pollution control in the Pearl River Delta (PRD) region of China. Biogenic volatile organic compounds (BVOCs) are the main precursors of O3 formation. Changes in vegetation type because of anthropogenic disturbances alter BVOCs emissions in the PRD. In this study, WRF-Chem4.1.2 coupled with MEGAN2.1 was applied to predict the impact of changes in BVOCs because of the replacement of vegetation plans on O3 pollution in the PRD. This is based on changes in the distribution of vegetation types in a range of sensitive areas. The results have indicated that the scenario with the greatest disturbance to O3 concentrations is the replacement of the forest type in the volatile organic compounds (VOCs) sensitive area with the dryland cropland and pastureland use type. Here, the reduction in isoprene concentrations in the PRD River could reach 63% of the area. The reduction in O3 concentrations reached 48% of the area, with a maximum reduction of 8.8%. The effect of vegetation planning on O3 has a clear “spillover” phenomenon. Variations in O3 concentrations greater than 1% were predominantly distributed outside the range of land use type changes, accounting for 80%–91% of the change. There was a linear fit for meteorological conditions and the amount of variation in precursor concentrations with O3 concentrations in the “spillover” region. BVOCs were found to have a greater effect on the variation in O3 concentrations.