Green System and Air Quality in Sevlievo Town, Bulgaria

Green system and urban dendroflora can affect air quality in the following ways: (i) converting carbon dioxide to oxygen through photosynthesis; (ii) intercepting particulate pollutants (PM10, dust, ash, pollen and smoke) and absorbing toxic gases such as ozone, sulphur dioxide, and nitrogen dioxide, (iii) emitting various volatile organic compounds contributing to ozone formation in cities (iv) lowering local air temperatures (v) reducing building temperature extremes in both summer and winter and consequently reduce pollution emissions from power-generating facilities. The aim of this study was to investigate the regulating service of urban dendroflora as a depot of carbon and the role of the green system as a reducer of dangerous for people PM10. In 2017 of the territory of Sevlievo Town were investigated 2555 trees of 45 species taxonomically belonging to 16 families and 30 genera. In 2019 using Huber's simple formula the trees biomass, biomass energy, absorbed CO2 and accumulated carbon of trees biomass in the streets, quarters and parks were calculated. The total biomass of the dendroflora in Sevlievo Town was found to be equal to 2892.65 t. The total carbon dioxide (CO2) in urban trees was 1446.33 t; the separated oxygen (O2) was 542.37 t and the accumulated carbon (C) was 394.45 t. PM10 in Sevlievo Town have high daily concentrations above the LD50.