Annual Distribution of Atmospheric Ammonia Concentration in Saemangum Reclaimed Land Area

BACKGROUND: More recently, it has been shown that atmospheric ammonia (NH3) plays a primary role in the formation of secondary particulate matter by reacting with the acidic species, e.g. SO2, NOx, to form PM2.5 aerosols in the atmosphere. The Jeonbuk region is an area with high concentration of particulate matter. Due to environmental changes in the Saemangeum reclaimed land with an area of 219 km2, it is necessary to evaluate the impact of the particulate matter and atmospheric ammonia in the Jeonbuk region. METHODS AND RESULTS: Atmospheric ammonia concentrations were measured from June 2020 to May 2021 using a passive sampler and CRDS analyzer. Seasonal and annual atmospheric ammonia concentration measured using passive sampler was significantly lower in Jangjado (background concentration), and the concentration ranged from 11.4 μg/m3 to 18.2 μg/m3. Atmospheric ammonia concentrations in Buan, Gimje, Gunsan, and Wanju regions did not show a significant difference, although there was a slight seasonal difference. The maximum atmospheric ammonia concentration measured using the CRDS analyzer installed in the IAMS near the Saemangeum reclaimed land was 51.5 μg/m3 in autumn, 48.0 μg/m3 in summer, 37.6 μg /m3 in winter, and 32.7 μg/m3 in spring. The minimum concentration was 4.9 μg/m3 in spring, 4.2 μg/m3 in summer, and 3.5 μg/m3 in autumn and winter. The annual average concentration was 14.6 μg/m3. CONCLUSION(S): Long term monitoring of atmospheric ammonia in agricultural areas is required to evaluate the formation of fine particulate matter and its impact on the environment. In addition, continuous technology development is needed to reduce ammonia emitted from farmland.