Our city, our trees, our choice
Why do we need trees in our cities? Urban areas are growing, which means more streets, parking lots and rooftops, and less green space. The United Nations projects that by 2050, 64 percent of the developing world and 86 percent of the developed world will live in cities. The projected economic, environmental and social effects of this tremendous urban growth is alarming. Most of these effects — such as increased carbon dioxide emissions and other air pollution, urban heat-island effect, decreased biodiversity and unhealthy living conditions — are correlated with decreasing green spaces. Urban greenery has a prominent place in ecophysiology research all over the world. The importance of trees and other vegetation, beyond their aesthetic contribution to the cityscape, is increasingly recognized. Their environmental, economic, health and social benefits provide indispensable resources for urban communities.
Environmental benefits
Trees clean the air by absorbing carbon dioxide, producing oxygen, and trapping airborne dust, smoke and pollen.
Trees cool the environment and increase humidity by providing shade and, through evapotranspiration, releasing water through leaves.
Trees help lower energy costs by cooling peak summer temperatures by 2 degrees to 9 degrees Fahrenheit. And trees help to reduce winter heating costs by blocking cold winds.
Trees help with stormwater management. Green spaces naturally absorb and filter stormwater, reducing contamination of city water from trash, bacteria, heavy metals or other pollutants. Urban trees also act as flood protection during intense rainfalls.
Economic benefits
Trees and parks increase business by creating a more pleasant environment for customers, employees and tourists.
Green spaces have a positive effect on residential home sales and can increase property values up to 15 percent.
Social and health benefits
Trees, parks and urban green spaces make cities more livable and healthier.
They create communities by providing opportunities to gather and enjoy outdoor spaces. Studies have shown that greener cities are healthier cities. People are more motivated to get outdoors and exercise if their environment is greener, which can help reduce obesity, heart disease and diabetes. The incidence of attention deficit hyperactivity disorder in children is decreased by spending more time in nature. Trees help to reduce asthma by filtering the air.
Research shows that there is less violence in neighborhoods where there are trees.
While the role of urban trees is invaluable, public awareness of their importance is crucial to their survival. Trees in densely populated areas face many challenges, such as crowding, poor soils, inadequate water and nutrient deficiency. Researchers and plant specialists are tirelessly seeking to understand how plants respond to environmental changes and which species of trees can adapt best to the wide range of unfavorable environmental factors in urban areas. But without the involvement and stewardship of local communities, municipal authorities and private investors, all the research will be in vain.
It is our city, our trees, our choice.
Marta Gyeviki has a Ph.D. in horticulture from Corvinus University in Budapest, Hungary. She was an assistant professor at the university and worked with both Hungarian and European farmer associations until moving to Santa Fe. She spends most of her time raising her two young sons, but in her free time, she joins other Master Gardeners at the Audubon Center learning and teaching about its network of native pollinators and plants.