Formation of environmental protection landscaping facilities in urban ecological systems

Abstract

Introduction: environmental gardening facilities on urban roads and streets are formed within limited-width dividing strips. At the same time, the increase in the phytomass density, which determines the shielding effect of tree plants, is not directly proportional to the total number of rows and the width of greenery belts, but mainly due to their most illuminated marginal rows. Hence there is a need to determine the optimal, in terms of gas-shielding efficiency, width, and density of the green spaces on the transport infrastructure facilities. Materials and methods: the observations were made in streets of cities and on models of different-design green strips. Results: the dependence of carbon oxide concentration decrease by green belts on their density and height was determined. The lowest concentration of automotive emissions behind green belts was observed at a distance of 1 to 1.5 belt heights, while the highest concentration was at a distance of 2 to 3 belt heights. In the “road-green belt-building” urban ecological system, the most effective scattering of pollutants along the building facades and at the pedestrian ways is present when trees reach medium floors of the buildings. As the green belt height approaches the height of the buildings, the air in yard space becomes cleaner. Conclusions: on main roads, it is necessary to form dense and evenly openwork greenery environmental belts of 15 to 30-meter width. The rows of plants closest to the driving lane edges should consist of shrubs in the form of a two-tier hedge and low-stem trees. On the main streets, the green strips should be used at the height of the medium floors of the buildings with an openwork factor within the range of 0.5 to 0.6. In case of the dense frontal building of the streets, the environmental protection belts should have a well-blown structure providing an optimal aeration mode and effective scattering of automotive emissions in pedestrian areas and at the facades of buildings.