There are many advantages that one can get when they live in a city that has rich ecosystems. Trees and plants reduce rainwater, remove pollution from the air, and most of all give off oxygen that people cannot live without. An organization names American Forests study the bad effects of the declining quality of forests to the city and its residents. They also provide information to the public about such facts that a human needs two trees to provide him or her adequate oxygen and so that the air pollution is reduces by 20 pounds a year. Parks helps cool the area, so that there is lesser need for aic-conditioning. Cars could be parked in shady areas, which meant that there is a 50 degree reduction of temperature compared to cars that are not under trees. Some places where the buildings and industrialization is thick have to create forests and parks artificially using human labor and makes sure to maintain them well.