151
tremendously as well as it detains nearly 30% runoff while for storms less than 1 in.,
the number rises to 90% [15, 16]. In addition, seasonal and physiological evapotranspiration rates of plants of the roof also affect the effectiveness of runoff control,
with summer growing season being better than winter. As the green roof is made up
of plants and trees, it has similar benefits as trees including the transformation of
water and air pollutants mentioned above [17, 18]. With the help of a 1000-squarefoot green roof, around 40 pounds of particulate matter can be removed annually,
which equals to the annual emission of 15 passenger cars [19, 20]. In addition to the
benefits of removing pollutants, green roofs can also provide climate change mitigation through managing temperature.
Finally the proper urban forestry management has been proposed since it is the
significant contributor to improve urban life quality, including having plenty of benefits including blocking and penetrating rainwater to avoid flooding and improving
water quality, absorbing and transforming air pollutants, providing wind breaks to
protect buildings from strong wind, and reducing heat island effect [21–23].
Therefore, planting and maintaining trees in urban area shall indeed be an excellent
option considering its benefits for resilience, adaptation, and climate mitigation.
According to estimation, a typical medium-sized tree can block around 2380 gallons of rainfall per year. When it comes to mitigating urban heat island impacts,
trees typically absorb 70–90% of sunlight in summer and 20–90% in winter (because
of the seasonal variation between deciduous trees and evergreens) and further
reduce the maximum surface temperature of the roofs and walls by 11–25 °C [24,
25]. The new shade trees, planted around houses, can lead to annual cooling energy
savings of 1% per tree and annual heating energy use can be decreased by almost
2% per tree [26–28]. Besides, direct energy savings from shading by trees could
reduce carbon emissions around 1.5–5% due to decreases in cooling energy use [29,
30]. As mentioned above, trees can absorb air pollutants; these include particulate
matter, sulfur dioxide, ground-level ozone, nitrogen oxides, and carbon monoxide.
As estimated by a research, urban trees in the USA remove 784,000 tons of pollutant per year, which creates $3.8 billion economic value [31, 32]. By increasing the
urban tree coverage rate such as in New York City by 10%, the ground-level ozone
can be cut down by 3%; besides, a quarter ton of NOx and over 1 ton of particulate
matter will be cut down per day with one million additional trees in the city [33, 34].
Eventually the proposition of better approach for the development of green infrastructure including sustainable urban design and planning and smart growth technology by incorporating the green infrastructure construction shall indeed overcome the
problems of stormwater and environmental crisis management [24, 35]. Subsequently,
the best management system must be practiced; especially where higher density
housing is present in populated area green management should be practiced, providing green open spaces, large-scale urban forestry projects in neighborhoods, and
greenbelts around cities in order to enable coastal wetlands to buffer against flooding. Besides, in flood zones, local building codes may be required to follow for raising buildings or bridges above current and future flood levels or setting the first
floors at floodable positions with the application of green management. As green
infrastructure is a method for creating more resilient metropolitan communities,
Methods and Materials
tremendously as well as it detains nearly 30% runoff while for storms less than 1 in.,
the number rises to 90% [15, 16]. In addition, seasonal and physiological evapotranspiration rates of plants of the roof also affect the effectiveness of runoff control,
with summer growing season being better than winter. As the green roof is made up
of plants and trees, it has similar benefits as trees including the transformation of
water and air pollutants mentioned above [17, 18]. With the help of a 1000-squarefoot green roof, around 40 pounds of particulate matter can be removed annually,
which equals to the annual emission of 15 passenger cars [19, 20]. In addition to the
benefits of removing pollutants, green roofs can also provide climate change mitigation through managing temperature.
Finally the proper urban forestry management has been proposed since it is the
significant contributor to improve urban life quality, including having plenty of benefits including blocking and penetrating rainwater to avoid flooding and improving
water quality, absorbing and transforming air pollutants, providing wind breaks to
protect buildings from strong wind, and reducing heat island effect [21–23].
Therefore, planting and maintaining trees in urban area shall indeed be an excellent
option considering its benefits for resilience, adaptation, and climate mitigation.
According to estimation, a typical medium-sized tree can block around 2380 gallons of rainfall per year. When it comes to mitigating urban heat island impacts,
trees typically absorb 70–90% of sunlight in summer and 20–90% in winter (because
of the seasonal variation between deciduous trees and evergreens) and further
reduce the maximum surface temperature of the roofs and walls by 11–25 °C [24,
25]. The new shade trees, planted around houses, can lead to annual cooling energy
savings of 1% per tree and annual heating energy use can be decreased by almost
2% per tree [26–28]. Besides, direct energy savings from shading by trees could
reduce carbon emissions around 1.5–5% due to decreases in cooling energy use [29,
30]. As mentioned above, trees can absorb air pollutants; these include particulate
matter, sulfur dioxide, ground-level ozone, nitrogen oxides, and carbon monoxide.
As estimated by a research, urban trees in the USA remove 784,000 tons of pollutant per year, which creates $3.8 billion economic value [31, 32]. By increasing the
urban tree coverage rate such as in New York City by 10%, the ground-level ozone
can be cut down by 3%; besides, a quarter ton of NOx and over 1 ton of particulate
matter will be cut down per day with one million additional trees in the city [33, 34].
Eventually the proposition of better approach for the development of green infrastructure including sustainable urban design and planning and smart growth technology by incorporating the green infrastructure construction shall indeed overcome the
problems of stormwater and environmental crisis management [24, 35]. Subsequently,
the best management system must be practiced; especially where higher density
housing is present in populated area green management should be practiced, providing green open spaces, large-scale urban forestry projects in neighborhoods, and
greenbelts around cities in order to enable coastal wetlands to buffer against flooding. Besides, in flood zones, local building codes may be required to follow for raising buildings or bridges above current and future flood levels or setting the first
floors at floodable positions with the application of green management. As green
infrastructure is a method for creating more resilient metropolitan communities,
Methods and Materials