Why Cities Need Trees for Air Quality

Cities are shifting to more eco-friendly urban landscaping and including more greenery. Vegetation creates better habitats for wildlife and people, but it also helps clean the air and reduce pollution. Trees improve air quality by shading surfaces and reducing temperature.By shading buildings and houses, trees reduce the need for air conditioning—thus reducing greenhouse emissions. Trees can directly remove air pollutants. Not only can they absorb carbon dioxide and emit oxygen, but trees also filter air pollutants like sulfur dioxide and nitrogen dioxide through their leaves, and effectively removing Particulate Matter (PM) from the environment. PM can cause severe health problems, but not all trees filter it in the same way. This difference widely depends on the canopy, leaf size and structure. Bigger canopies can trap smaller particles, and larger leaves trap more pollutants than smaller ones. Also, leaves with rough surfaces have higher efficiency when filtering PM. Research shows that tiny hairs on the leaves can trap solid and liquid particles of PM