Environ Monit Assess. 2025 Mar 31;197(4):492. doi: 10.1007/s10661-025-13957-z.
ABSTRACT
The spatial distribution of particulate matter pollution in urban areas is as complex as the complexity layout of buildings and streets and the various emission sources. Because of relatively high costs and inflexibility, the traditional fixed station monitoring is not able to satisfy the demand of dynamic particulate monitoring. A particulate sensor (OPC_N3) was installed on a trailer of a bicycle and applied to investigate spatio-temporal distributions of PM2.5 and PM10 concentrations in summer time of Karlsruhe, Germany. Before that, the sensors were calibrated against a standard instrument (Fidas200). Temporal variations show that PM2.5 and PM10 mass concentrations in the morning were on average higher 2.7 ± 1.2 µg/m3 than in the afternoon and evening. The highest PM2.5 and PM10 concentrations were observed in the southern forest of Karlsruhe (segment 9), and the street surface is the primary influencing factor. Walking at 5 km/h has a higher concentration than speed at 5 km/h of riding. When riding at different speeds on the same gravel and potholed path, higher speeds are associated with higher particulate matter (PM) concentrations. Distribution pattern of particulate matter on workday and weekend was also different: Mean PM2.5 and PM10 concentrations of southern forest (segment 10) in the morning and evening at weekend are on average higher by 11.2 ± 10.3 µg/m3 than at workday. Construction activities on workday also had significant effect on particulate matter concentration. Spatial distribution of aerosol concentrations was highly depending on land use and city structure. These results provide good insights for the application of low-cost sensors in urban environments monitoring and a basis to develop potential mitigation measures.
PMID:40164845 | DOI:10.1007/s10661-025-13957-z
