Rooftop gardens contribute to the reduction and filtering of polluted air particles and gases, not only through the plants and the photosynthesis process but also by deposition in the growing space.
Green roofs may also help reduce the distribution of dust in the air and the production of smog, which leads to decreasing greenhouse emissions in urban areas.
Probably one of the most impressive and important benefits of rooftop gardens is how they positively affect the Urban Heat Island effect. The UHI concept is based on the increased temperature levels found in pretty much all urban areas. Because the sun warms up concrete faster than it does plants and trees, and because concrete is more abundant in urban areas, the city becomes a big hot-aired area (heat island) all year round. This makes cities extremely hot in summer, leading to increased use of air. conditioners and other cooling technologies.
Other than the different types of bushes, trees, plants, and invertebrates rooftop gardens can harvest, they can also be a perfect habitat for many birds, and act as a stopover for migrating species, allowing two different type of these to come into contact.