7 Benefits of Urban Trees
19 July, 2021 | Oviyaa Venkateshwaran
- Urban trees are critical to tackle environmental issues, intense weather events and improve livability in cities.
- The right species of trees are proven to reduce the temperature by up to 9% in cities, offering the potential to tackle heatwaves.
- Trees can provide positive mental health for people living in a busy urban lifestyle.
By 2050, 68% of the global population are estimated to live in urban areas. The migration of rural to urban regions enables rapid development without proper land use planning, especially in Asia and Africa.
With more population moving into cities, retaining urban trees, and planting more ones are needed to enhance the natural environment in urban areas and fight against climate change.
Public green space is a significant element in public spaces. Even a short intervention of nature is a huge benefit for the city, people, and the planet.
1. Tackles Air Pollution
Urban regions are more prone to air pollution. Automobiles, buildings, and construction are some of the major causes of air pollution in cities.
Many cities in the world like London, Milan and Paris are making efforts to plant trees to improve air quality.
The urban forest can reduce air pollution by filtering urban pollutants and fine particles. They capture pollutant gases and filter fine particulates like dust, dirt and smoke that gets trapped on leaves and barks of trees.
Studies have revealed a 60% decrease in particulates from car exhaust fumes on streets covered with trees.
Planting the right species of trees in proper locations is important since some tree species are more effective to reduce pollution in urban centres.
For example, evergreen trees are exceptional pollutant trappers and can work throughout the year. Pine species and common yew are other tree species that are adequate for cities.
2. Reduces Carbon Emissions
Trees play a vital role in climate change mitigation. They support decreasing carbon emissions and conserving energy.
Incorporating trees in the building reduces the building’s energy use by decreasing the use of cooling equipment. In turn, this reduces energy bills for an urban dweller.
According to the UN, a tree can capture up to 150 kgs of carbon dioxide per year. This creates sustainable cities and supports several cities to achieve their climate targets.
3. Mitigates Urban Heat Island Effect
With the rise in global temperature and frequent heatwaves hitting urban regions, finding ways to cool the urban environment is significant in cities. Cars, urban infrastructure, and buildings intensify the temperature experienced in urban areas, especially during summer.
The solid, dark asphalt and brick surfaces capture nearly all the incoming short-wave radiation from the sun, warming between 40oC and 60oC, and retaining energy which is later let out into the air after sunset when it can be caught between the streets. More and more natural land cover is being replaced with grey infrastructure which absorbs and retain heat.
The urban heat island effect occurs when an urban environment is warmer than its surrounding rural areas. In general, to mitigate warmer areas, natural solutions are the most sustainable way of tackling the urban heat island effect.
Urban trees tackle the heat by preventing the radiation before it hits the ground and using the energy for evapotranspiration. Evapotranspiration takes place when the sun ray’s hit the trees’ canopy, inducing water to evaporate from the leaves. This cools them down by decreasing the amount of energy left to heat the air.
Planting trees enhances the overall temperature of the area, providing a comfortable temperature for both the residents and tourists. Studies reveal that a city with trees in the built environment can reduce the temperature of the city by up to 9oC.
Studies have revealed that one mature tree can generate the same cooling mechanism as 10 room-sized air conditioning systems. Moreover, trees can reduce nearly 10% of local energy consumption through their mitigating the local climate.
Trees act as an urban cooling element that provides shade and reduces temperature by deflecting the radiation from the sun and releasing moisture into the air. Trees tackle heatwaves and provide a comfortable urban environment for people living in cities.
Trees can reduce the temperature of the city by up to 9oC.
4. Supports natural habitat
Enhancing and maintaining biodiversity is vital for a sustainable city. Increasing tree cover in cities increases biodiversity and protects habitats on land and in water. It provides the plants and animals with the necessary food and protection.
Parks, forests, and other green spaces play a significant role in increasing biodiversity and supporting natural habitats in cities.
5. Mitigates flooding
Nowadays, a greater number of urban areas are prone to frequent flood events. Building a flood-resilient city requires landscape elements that can control water.
With water runoff being a serious problem due to infrastructural developments, trees are significant to manage stormwater, mainly in an urban ecosystem. They support reducing the stormwater runoff and enhancing the water quality. Trees build a resilient infrastructure for cities by managing floodwaters.
An area with a 5% tree canopy can reduce up to 2% of stormwater runoff.
6. Increases property values
Incorporating trees and landscapes in spatial planning of towns or neighbourhoods can enhance property value to about 20%, thereby attracting residents, business, and tourism. According to a study, the commercial offices with a 7% high rental price have a high-quality landscape.
Trees provide increased benefits by raising property values and selling prices. The property’s market value increases with the presence of trees in front of the house and the neighbourhood.
7. Supports Health and Well-being
Since trees are effective at eliminating particulate matter, the improved air quality prevents lung, respiratory and cardiovascular disease that is linked to fine particulate matter.
Trees lessen the effects on skin cancer, hypertension, lessening smog formation, offering shade from the sun, and giving attractive, peaceful areas for recreation.
While living in urban areas has its positive benefits, but it can sometimes contribute to mental health problems such as stress, anxiety, negative thoughts, and depression due to fast-paced lifestyles. COVID-19 pandemic and intense lockdowns showed an increase in stress and poor mental health.
Studies show that green spaces can contribute to positive mental health. Connecting with nature has proven to support psychological well-being. Being close to nature allows people to relive the stress of the city lifestyle.
Moreover, the presence of trees in cities encourages physical activity. Proximity and easy access to trees and green spaces decreases mental illness and contributes to a healthier urban community.
Trees act as a sound-absorbing barrier to support in reducing noise pollution.
Recognizing the benefits of trees will allow city leaders, local authorities, developers, and landscape planners to include trees in strategic planning and tackle climate change.