This paper provides the analysis of the impact of vegetation on water erosion, winter conditions, visibility of formation line, glare effect, inhibition of energy, wind strength, presence of animal habitats and creation of specific microclimate. Apart from typical ecological functions, they also impact the risk for people involved in the traffic flow. Depending on a type of distribution or the model of design, vegetation shields may reduce the speed of wind or, conversely, may intensify it and cause turbulence. The proper selection of plant features helps to influence the strength and location of side winds along a road, speed of wind, accumulation of dust, snow, ice and the location of cold, warm, wet and dry places. The attenuation of the microclimate, i.e. variations in air temperature, insolation and winds, is another factor that justifies and supports introducing vegetation along streets and roads. These influences have both a positive and negative impact on the safety of vehicle flow on roads. Rationally distributed, they may serve not only as decoration, but also effectively lessen the impact of weather conditions on the movement on roads.

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