Treffer: Impact of different crop residue burning activities on seasonal variation in ambient air quality

Abstract The large-scale burning of rice, wheat, and sugarcane residues significantly impacts air quality, contributing to climate change and severe health risks. This study aims to analyze the seasonal variations in pollutant levels along with meteorological factors. The findings revealed that rice residue burning leads to a 57.7% increase in the PM2.5 concentration above the NAAQS limit and a 184% increase in the benzene level, making it the most polluting crop. Sugarcane burning results in the highest PM2.5/PM10 ratio (0.59), indicating a dominance of fine particulate matter, along with a 61.9% increase in CO emissions. Wheat burning, although lower in emissions, contributes to 49.7% higher PM10 levels, with benzene exceeding NAAQS by 134%. Comparative analysis reveals that PM2.5, PM10, and benzene consistently exceed permissible limits across all burning seasons, with rice burning resulting in the most severe violations. VOC ratio analysis revealed a decrease in the toluene/benzene (T/B) ratio, suggesting a disproportionate increase in benzene emissions, particularly during the sugarcane and wheat burning periods. The PM2.5/PM10 ratios increase during burning periods, reflecting the higher fraction of fine inhalable particles that pose severe respiratory hazards. AQI analysis highlights a shift from moderate to poor air quality during burning periods, with rice burning frequently pushing the AQI into the “very poor” category. Correlation analysis revealed strong associations between PM2.5, CO, NO₂, and VOCs, with pollutant retention exacerbated by temperature inversions, low wind speeds, and high humidity levels, contributing to smog formation and prolonged pollution episodes. These results confirm that crop residue burning is a major driver of seasonal air pollution, with rice burning causing the most extreme exceedances, followed by sugarcane and wheat burning. The high PM2.5/PM10 ratios and VOC correlations further emphasize the critical role of fine particulate and toxic emissions, whereas the AQI trends reveal an alarming deterioration in air quality during the burning season. These findings underscore the urgent need for targeted residue management strategies, including integrated monitoring systems, regulatory enforcement, giving financial incentives for bioenergy utilization, and biochar production, to mitigate seasonal pollution spikes. This study provides essential insights for policymakers in balancing sustainable agricultural practices, air quality improvement, and public health protection.