Trees and greenery create shade for surrounding objects by absorbing sun’s radiation on city infrastructure. This has a specially positive influence on decreasing heat islands in cities. For ex. park temperatures can be 2°C lower than temperatures in areas outside parks and it has been proven that green infrastructure lowers city temperature by 9°C in very warm areas. In the winter, when warmth is needed, planting trees that lose their leaves in autumn and winter allows the Sun’s rays to pass through to city surfaces.
We all know that plants increase oxygen levels in air, while simultaneously decreasing carbon dioxide level. For ex. one ha of forest uses 8kg of carbon dioxide per hour, the same amount that 200 people produce in one hour.
Toxic gases and traffic particles are polluting city atmosphere and depending on the intensity, pollution could have detrimental effects to people’s health. City greenery decreases the negative effect of those particles as they keep them on their branches and leaves.
Greenery in a city and its surrounding areas has many advantages. With their form, manner in which they grow and their environmental significance, the plants are irreplaceable natural elements that make city life better. Green surfaces in a city positively impact their surroundings by influencing city microclimate. This is best shown by reducing high temperatures, rising air humidity and regulating wind strength, purifying air and decreasing city noise.
Having greenery throughout a cityscape, creates not only paths for people to move and navigate around cities, but are also of extreme importance for a sustainable city development. Cities develop concepts of green surfaces as networks of ecosystems of various greenery - urban parks, green alleys next to traffic roads, connected parks, sport and leisure parks, green roofs.