Effect of urban lake wetlands and neighboring urban greenery on air PM10 and PM2.5 mitigation

Urban wetlands can support a reduction in particulate matter (PM) concentrations in their neighbouring areas. However, the local environmental effect can be disturbed/intensified by surrounding built-up underlying surfaces, e.g. traffic roads and green spaces. This paper investigated the coupling effect of urban lake wetlands and the neighbouring greenery within 500-m transects of the built-up environment on air PM10 and PM2.5 levels in Wuhan, China. According to the lake wetland-green space land use regression (LWGS LUR) analysis, models for air PM10 and PM2.5 were successfully built with an adjusted R2 of 0.839 and 0.890, respectively. Correlation analysis revealed that the LSI_wetland (landscape shape index), PD_G_b (patch density), NDVI_b and RH_b (relative humidity) variables were strong predictors of air PM10 levels; additionally, AR_wetland (area), LSI_G_b and RH_b were strong predictors of air PM2.5 levels. The positive impact of lake wetlands and neighbouring greenery on PM concentrations was significant in the 300-m buffer or closer. Moreover, the effect could be shaped by changing the time interval; the highest air PM10 concentration difference of 53.8 μg/m3 among five time intervals occurred in the 300-m buffer, while for the air PM2.5, the highest difference was 29.8 μg/m3 in the 100-m buffer. [Display omitted] •Lake wetland-green space land use multiple regression model for PM works up to 500-m.•Urban lakes can support a reduction in PM concentrations in the neighbouring area.•Combination of lakes and greenery improves urban air quality.•Positive impact of lakes and greenery on PM pollution is significant up to 300-m.