Urban forests play a major role in the green city movement, as rapid and global urbanization raises concerns about the sustainability of cities. As valuable components of the urban environment, urban forests enhance local communities by providing the following ecological, social, and economic benefits:

• Climate protection
• Air quality improvement
• Water quality improvement
• Ecological stability (habitat and biodiversity)
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• Aesthetically pleasing recreational and educational spaces
• Opportunities for community involvement
• “Green-collar” employment opportunities
• Improvement of land values and the local tax base

More than half of the world's population lives in urban areas, and urban forests help to protect the climate from the problems associated with the resource demands of this burgeoning population. Healthy urban forests mitigate the problems associated with the urban heat island, and urban trees and forests reduce the amount of energy associated ...