We present results of the 5-year monitoring of ambient O3 concentrations in a Central European medium altitude mountain forested area. O3 levels were measured at 11 sites between 714 and 1000 m a.s.l. in 2006-2010 vegetation seasons using Ogawa diffusive samplers. Our results reveal that O3 exposure in the Jizerské hory Mts. was relatively high and comparable with polluted sites in Southern Europe and in higher altitudes. O3 concentrations differed significantly between individual sites and in individual years. O3 concentrations showed clear dependence on altitude at sites with similar aspect. Its gradient for the entire 5-year period under review equaled 3.5 ppb/100 m of altitude, ranging between nearly 5 ppb/100 m of altitude in 2006 and nearly 3 ppb/100 m of altitude in 2010. O3 concentrations at the site with northern aspect were consistently significantly lower than at the site at similar altitude with southern aspect. O3 concentrations measured at the forest edge were consistently lower than those measured at the same site but at the forest clearing. It is evident that the macro-setting of the O3 monitoring site is crucial for obtaining reliable results with high representativeness for the area.

• Keywords
• Ambient ozone, Diffusive samplers, Spatial and temporal variations,
• MeSH
• Air Pollutants analysis   MeSH
• Forests MeSH
• Environmental Monitoring MeSH
• Altitude MeSH
• Ozone analysis   MeSH
• Seasons MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Geographicals
• Czech Republic MeSH
• Names of Substances
• Air Pollutants MeSH
• Ozone MeSH

Political and economical transition in the Central and Eastern Europe at the end of eighties significantly influenced all aspects of life as well as technological infrastructure. Collapse of outdated energy demanding industry and adoption of environmental legislation resulted in seeming improvements of urban environmental quality. Hand in hand with modernization the newly adopted regulations also helped to phase out low quality coal frequently used for domestic heating. However, at the same time, the number of vehicles registered in the city increased. The two processes interestingly acted as parallel but antagonistic forces. To interpret the trends in urban air quality of Prague, Czech capital, monthly averages of PM(10), SO(2), NO(2), NO, O(3) and CO concentrations from the national network of automated monitoring stations were analyzed together with long term trends in fuel consumption and number of vehicles registered in Prague within a period of 1992-2005. The results showed that concentrations of SO(2) (a pollutant strongly related to fossil fuel burning) dropped significantly during the period of concern. Similarly NO(X) and PM(10) concentrations decreased significantly in the first half of the nineties (as a result of solid fuel use drop), but remained rather stable or increased after 2000, presumably reflecting rapid increase of traffic density. In conclusion, infrastructural changes in early nineties had a strong positive effect on Prague air quality namely in the first half of the period studied, nevertheless, the current trend in concentrations of automotive exhaust related pollutants (such as PM(10), NO(X)) needs adoption of stricter measures.

• MeSH
• Air Pollutants analysis   MeSH
• Environmental Monitoring methods   MeSH
• Nitrogen Dioxide analysis   MeSH
• Nitric Oxide analysis   MeSH
• Sulfur Dioxide analysis   MeSH
• Carbon Monoxide analysis   MeSH
• Ozone analysis   MeSH
• Particulate Matter analysis   MeSH
• Vehicle Emissions analysis   MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Geographicals
• Czech Republic MeSH
• Names of Substances
• Air Pollutants MeSH
• Nitrogen Dioxide MeSH
• Nitric Oxide MeSH
• Sulfur Dioxide MeSH
• Carbon Monoxide MeSH
• Ozone MeSH
• Particulate Matter MeSH
• Vehicle Emissions MeSH