Particulate matter (PM) diameter and shape are the most discussed physical properties considering behaviour characterisation, source identification, and possible effects on human health. Some groups of particles not only have a typical chemical composition but also a specific shape reflecting the method of their formation, so it is possible to deduce the source. A scanning electron microscope VEGA TS 5136 LSU (Tescan, s.r.o., Czech Republic) was used for PM imaging. PM air samples were captured on Millipore special filters made of polycarbonate membrane (Isopore) with a 0.6 µm size of pores. PM samples were taken both from near the exhaust of gasoline and diesel engines to define PM shapes emitted from combustion processes in vehicles, and also from chosen localities that represent urban sites with different traffic intensity and with different possible PM sources (transportation, industry). Samples of street dust were also collected by sweeping with a broom and with a vacuum cleaner to identify PM generated by resuspension. Separate spherical particles were observed on exposed filters near a gasoline vehicle's exhaust pipe and their aggregates near a diesel vehicle's exhaust. Spherical particles aggregates were also observed on filters exposed at a locality with a high traffic intensity where road traffic is considered to be the dominant source of air pollution. Larger spherical particles that represent the products of coal combustion were found at a locality near an industrial area. Other particle shapes, excluding spherical particles, were often observed at the localities that represent a more open area with more trees. Sharp-edged particles of geological origin (soils) and larger spherical or elongated particles of biological origin (spores) were also often observed on the filters from these localities which is evidence of a significant contribution of other processes to the overall PM air pollution, namely resuspension.

The value of selected emission factors was monitored in the operation of an older type of engine testing bench using diesel and compared with the same parameters monitored under similar conditions with the addition of the additive, Envirox TM . It was found that the additive based on CeO 2 nanoparticles reduces emissions of hydrocarbons C x H y , and NO x , while emissions of CO 2 remain comparable or slightly lower and CO emissions even significantly increase. Dependence of tested emissions on reduced torque TM R , engine power P and revolutions f was observed as well.

The dispersion of particulate matter emitted by road transport to the vicinity of roads is predominantly influenced by the character of the air velocity field. The air flow depends on factors such as the speed and direction of the blowing wind, the movement of cars, and the geometries of the buildings around a road. Numerical modeling based on the control volume method was used in this study to describe the relevant processes closely. Detailed air velocity fields were identified in the vicinity of a straight road surrounded by various patterns of built-up urban land. The evaluation of the results was generalized to exponential expressions, affecting the decrease of the mass concentration of fine particles with the increasing distance from the road. The obtained characteristics of the mass concentration fields express the impact of the building geometries and configurations on the dispersion of particulate matter into the environment. These characteristics are presented for two wind speeds, namely, 2 m·s−1 and 4 m·s−1. Furthermore, the characteristics are introduced in relation to three wind directions: perpendicularly, obliquely, and in parallel to the road. The results of the numerical simulations are compared with those obtained via the in-situ measurements, for verification of the validity of the linear emission source calculation.

Construction of motorways and road traffic bring a new line element into the landscape, which fundamentally influences the local hydrological regime and water quality. Impermeable surfaces are introduced into the landscape, affecting the natural infiltration of water in the environment. The aim of the present research was to assess the long-term historical development of changes in the landscape retention potential due to construction of the D1 motorway in the Jihlava region and also evaluate the impact of winter maintenance on the quality of surface waters and soils. During the reference period, the research area showed an increase in land take and related increases in soil sealing by impermeable surfaces due to the construction of the D1 motorway. This fact has clearly contributed to the deterioration of the retention potential of the landscape in the area. Chloride concentrations of both matrices were evaluated in relation to the amount of de-icing salt applied at the sites and precipitation recorded in this region. Water samples collected at the outflow contained in all cases higher concentrations of chloride than samples of the inflow water. The highest chloride concentration in soil was measured in samples collected at a distance of 2 m from the road.

The paper assesses the development of land use and a road network from 1836 to 2016 in the Hodonín region (Czech Republic). The aim of the article is to verify relationship between the road construction and land use changes in their vicinity. The intensity of land use change processes between adjacent periods was calculated at various distances from roads. ESRI’s geographic information systems and geostatistics were used. This helped in assessing significance of impact of road vicinity on land use changes. The time interval of periods for comparison varied between 25 and 80 years due to availability of historical sources. In each period about 20% of the region was affected by land use changes. After the roads were built, there was an increase in the intensity of land use changes in their vicinity. It has been proofed that presence of a road can be considered one of the driving forces of long-term land use changes in this region. This so-called technological driving force impacted mainly urbanisation and other anthropogenic processes, agricultural intensification and grassing. Its significance is gradually increasing due to urbanisation, industrialisation, motorization and the rising mobility. Our results from the Hodonín region indicate that urbanisation and other anthropogenic processes have the closest relationship with the distance from major roads.

The article provides information about a new device, AlgaTox developed in the R&D project sponsored by the Technology Agency (n.TA02030179) and patented in Czech Republic (CZ 305687). Its functionality is based on the use of biosensor, and its main advantage is fast response rate. The toxicity detection is achieved through precise measurement of green algae oxygen production dynamics after their exposure to light of wavelength of 680 nm. Clark sensor with a resolution of 0.05% of the equilibrium oxygen concentrations and stability at a constant pressure and temperature of 0.1% of the equilibrium oxygen concentration at the 24-h measurement is used for the oxygen detection. Laboratory testing of the device has been made using silver nitrate, substance with known inhibitory effect on algae. Real samples of aqueous soil extracts and waste sample from old dried-up industrial tailing pond enriched with insecticide have been also tested. The values of oxygen production inhibition or stimulation determined with the new device in the evaluation of real samples were up to six times higher in comparison with the corresponding values of inhibition (stimulation) of growth rates determined by standard procedure.

Parks embody an important element of urban infrastructure and a basic type of public space that shapes the overall character of a city. They form a counterweight to built-up areas and public spaces with paved surfaces. In this context, parks compensate for the lack of natural, open landscapes in cities and thus have a fundamental impact on the quality of life of their inhabitants. For this reason, it is important to consider the quality of the environment in urban parks, air quality in particular. Concentrations of gaseous pollutants, namely, nitric oxide (NO), nitrogen dioxide (NO2), and ozone (O3), were measured in parks of Brno, the second-largest city in the Czech Republic. Relevant concentration values of PM10 solids were determined continuously via the nephelometric method, followed by gravimetric method-based validation. The results obtained through the measurement of wind direction, wind speed, temperature, and relative humidity were used to identify potential sources of air pollution in parks. The “openair” and “openairmaps” packages from the OpenSource software R v. 3.6.2 were employed to analyze the effect of meteorological conditions on air pollution. Local polar concentration maps found use in localizing the most serious sources of air pollution within urban parks. The outcomes of the analyses show that the prevailing amount of the pollution determined at the measuring point most likely originates from the crossroads near the sampled localities. At the monitored spots, the maximum concentrations of pollutants are reached especially during the morning rush hour. The detailed time and spatial course of air pollution in the urban parks were indicated in the respective concentration maps capturing individual pollutants. Significantly increased concentrations of nitrogen oxides were established in a locality situated near a busy road (with the traffic intensity of 33,000 vehicles/d); this scenario generally applied to colder weather. The highest PM10 concentrations were measured at the same location and at an average temperature that proved to be the lowest within the entire set of measurements. In the main city park, unlike other localities, higher concentrations of PM10 were measured in warmer weather; such an effect was probably caused by the park being used to host barbecue parties.

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