Three combined investigations were conducted to examine the sources of PM_2.5 in agricultural areas. The first was the measurement of PM_2.5 and gaseous compounds in the greenhouse, which is a relatively closed system, while the second was the analysis of pesticide components used in agricultural areas. Finally, the physical and chemical properties of PM_2.5 were analyzed in an orchard area and compared with the results of the greenhouse and agricultural chemical analyses. As a result, this research was able to confirm the source of emission and characteristics of PM_2.5 originating from the agricultural area. Volatile organic compounds (VOCs) in agricultural areas are emitted by agricultural chemicals, and the discharged agricultural chemicals are first absorbed into the soil, and then released into the air by evaporation. Finally, the secondary products of PM_2.5 in agricultural areas were estimated to have positive relationships with the VOCs from agricultural chemicals, and NH₃ from fertilizers. The photochemical reactions of VOCs and NH₃ were responsible for the impact on secondary products.

This study aimed to identify the characteristics of atmospheric pollutants emitted by agricultural activities and to evaluate factors that may cause harm to human health. For the research, atmospheric pollutants were measured over the course of a year in representative rice farming and field crop farming areas in South Korea. The results confirmed that the characteristics of atmospheric pollutants in agricultural areas are influenced by the nature of agricultural activities. Specifically, when comparing rice paddies and field crop areas, during summer, the correlation between oxidative potential and levoglucosan—a marker for biomass burning—weakens due to less burning activity in the rice-growing season, leading to lower oxidative potential despite different PM_2.5 across areas. The study also finds that methyl sulfonic acid, indicating marine influence, plays a big role in keeping oxidative potential low in summer. This suggests that the main causes of PM_2.5-related health risks in the area are from biomass burning and external sources, with burning being a significant factor in increasing oxidative potential. Based on these results, it is hoped that measures can be taken in the future to reduce atmospheric pollutants in agricultural areas.

Biomass burning is largely divided into six types: open burning, agricultural waste burning, meat and fish roasts, wood stoves and boilers, furnaces, and charcoal burners. Biomass burning is largely characterized by incomplete combustion due to the difficulty of appropriate control, which results in the emission of a large amount of air pollutants and the generation of harmful substances such as volatile organic compounds (National Institute of Environmental Research, 2014). Burning agricultural residue releases a large amount of fine particulate matter (PM). Open burning of agricultural residue, burning agricultural residues without incineration facility, in the rural areas are frequently observed Therefore, management based on accurate analysis of emission characteristics is needed. In Korea, most agricultural residues except for rice straw are incinerated in the field. Agricultural residues with a high incineration ratio are Chili and Perilla. The characteristics of PM emission by agricultural residues combustion were analyzed for Chili and Perilla. PM measuring equipment are Stack sampling system and Cascade Impactor (PM10, PM2.5 Impactor, Johnas, Paul Gothe GmBH). This study, the emission characteristics of PM-10, PM-2.5 generated in the combustion of agricultural residues were examined in consideration of moisture content.

In this study, the impact of long-range transport, one of the factors contributing to the presence of PM_2.5, was examined, and an analysis of marker compounds associated with its long-range transport was conducted. Aerosol optical depth, wind field, CO/CO₂ back-trajectory analysis, and satellite observation results were performed to determine PM_2.5, volatile organic compound (VOC), CO, CO₂, SO₂, O₃, NO, NO₂, and NH₃ levels at an orchard located in Jeollabuk-do, Republic of Korea. The characteristic of long-range transport at the observation area was evaluated during the research period. The concentrations for long-range transport based on concentration changes in gaseous materials and composition changes in PM_2.5 were analyzed. A back-trajectory analysis for the ratio of CO to CO₂ with satellite observation results was used to identify long-range transport. Furthermore, the proportionality between the ratio of 1,2-dichloroethane to naphthalene in VOCs and the quantity of precursor compounds linked to long-range transport were observed.

Ammonia is one of the precursor gases in the formation of particulate matter (PM) that reacts with nitrogen oxides and sulfur oxides in the atmosphere. Based on the Clean Air Policy Support System (CAPSS) of Korea, the annual ammonia emissions amounted to 261,207 tons in 2020 and the agricultural source (manure management sector) contributes the highest proportion of the ammonia inventory. However, the methodology for the study of ammonia emissions in Korea has some limitations regarding the representativeness of the sites selected and the reliability of the measurement method. In this study, we aimed to recalculate the ammonia emissions from the livestock industry in Korea using the UK’s estimation method, which uses the life cycle assessment of livestock manure. Three major animal types, i.e., cattle (beef cattle and dairy cows), pigs and chickens, and three major processes based on the manure flow, i.e., housing, manure storage and treatment and land application processes, were considered. The total ammonia emissions were estimated to be approximately 33% higher than the official ammonia emissions stated by the CAPSS. For the manure flow, the ammonia emissions were the highest from land application processes. The ammonia emissions from dairy cow and poultry manure were much higher than those stated by the CAPSS, while the emissions from beef cattle and pig manure showed similar levels. The methodology used in this study can offer an alternative approach to the ammonia emission estimation of the manure management sector in the agriculture industry of Korea. Korean emission factors based on the manure flow should be developed and applied in the future.

Fine particulate matter (PM_2.5) is a major air pollutant that significantly affects both human health and atmospheric chemistry. Although it has been extensively researched in urban and industrial areas, studies focusing on its characteristics in agricultural regions remain limited. This study aimed to analyze the chemical composition of PM_2.5 in the agricultural areas of Jeonbuk-do, South Korea, and assess the seasonal variations in its components. Air quality monitoring stations were established in a paddy field (Buan) and an upland field (Gochang) from June 2022 to May 2024. Continuous measurements of PM_2.5, PM₁₀, and gaseous precursors such as NH₃, NO_x, and SO₂ were performed, and the concentrations of organic carbon, elemental carbon, and major ions (Na⁺, NH₄⁺, K⁺, Ca₂⁺, Mg₂⁺, Cl⁻, NO₃⁻, SO₄²⁻) in PM_2.5 were analyzed in PM_2.5 were analyzed. Results indicated that ionic species were the dominant component, accounting for > 40% of the PM_2.5 mass. SO₄²⁻ and NO₃⁻ concentrations varied seasonally, with SO₄²⁻ levels peaking in summer and NO3 − concentrations peaking in winter. NH₄⁺ concentrations were consistently higher in the agricultural areas than in urban and industrial sites, highlighting the contribution of agricultural emissions. These findings underscore the necessity of dedicated air quality monitoring in agricultural regions to elucidate the mechanisms of PM_2.5 formation and determine their implications for rural air quality management.