Study on Load-Carrying Capacity Zoning in Atmospheric Environment in Developing Countries — A Case Study of Can Tho City, Vietnam

Air pollution in major cities of developing countries is a matter of great concern for managers, scientists, and people. In recent years, many studies have been done to simulate and forecast air quality for big cities in Vietnam as well as in the world with many air quality models have been used. However, studies using air quality models to evaluate the capacity of receiving air emission load in the atmospheric environment in local scale have not been carried out, especially in Vietnam. Therefore, the objective of this study is to assess load-carrying capacity in the atmospheric environment on a local scale for a smaller city at Mekong Delta, with a case study of Can Tho city, Vietnam. The FVM-TAPOM model system was established for the study area with the smallest grid resolution of 2km x 2km. The study results show that the atmospheric environment in Can Tho city still can receive more air emissions according to two seasons of the year (dry and rainy seasons) which are different depending on the seasonal wind direction. The central districts of Can Tho city (Ninh Kieu, Cai Rang, Binh Thuy, O Mon, and Thot Not) can only receive a smaller amount of emissions compared to the others (Vinh Thanh, Co Do, Thoi Lai, and Phong Dien). The amount of air emissions that can be received at the central districts is as follows: CO from 82,000 to 172,000 tons/year/district (696 – 2,142 tons/year/km2); SO2 from 3,800 to 4,900 tons/year/district (31 – 56 tons/year/km2); NOx from 217 to 328 tons/year/district (1.8 – 3.4 tons/year/km2). Similarly, the remaining districts can be received the emission is 164,000 – 653,000 tons of CO/year/district (1,308 – 2,555 tons/year/km2); 5,500 – 7,300 tons of SO2/year/district (17 – 29 tons/year/km2) and 31,000 – 44,000 tons of NOx/year/district (77 – 147 tons/year/km2).