Published on October 16th, 2012 | by James Ayre4
Cities Will Greatly Benefit from More Greenery as Urban Areas Rapidly Expand, UN Report Finds
As urban areas of the world continue to grow, there is a great opportunity to improve cities, making them healthier for people, simply by increasing greenery, according to a study released by the UN on Monday.
It’s been estimated that urban areas will more than double in size by 2030. With proper measures in place, this growth can greatly improve the quality of life for those living in cities.
Some of those measures are to increase parks, trees, and rooftop gardens and greenery. These actions can, somewhat surprisingly, go a long way towards decreasing city pollution, as well as helping to protect local plants and animals. This is considered especially important in rapidly growing nations like China and India, where city growth can occur practically overnight.
“Rich biodiversity can exist in cities and is extremely critical to people’s health and well-being,” wrote Thomas Elmqvist of the Stockholm Resilience Centre, scientific editor of the Cities and Biodiversity Outlook.
Urban populations throughout the world are expected to dramatically rise in the coming years, from around 3.5 billion currently to over 4.9 billion by 2030, according to the assessment by the UN Convention on Biological Diversity.
And the area that these cities take up is expected to rise expand by at least 150 percent.
“Most of this growth is expected to happen in small and medium-sized cities, not in megacities,” according to the report, issued to coincide with a UN meeting on biodiversity in Hyderabad, India.
By adding more greenery to cities, significant amounts of pollution and dust can be filtered out of the air fairly well and do some to limit the heat-trapping effects of local carbon dioxide emissions. There has been some recent research that has shown that the local presence of trees can do a decent job of reducing asthma and allergies for children living nearby.
The study also makes the point that cities are currently serving as the environment to a wide assortment of plants and animals.
Incredibly, “more than 65 percent of Poland’s bird species are found in Warsaw. In South Africa, Table Mountain national park, rich in wildlife, is surrounded by the Cape Town municipality. In the United States, Saguaro national park is just outside Tucson.”
“Sustainable urban development that supports valuable ecosystems presents a major opportunity for improving lives and livelihoods,” said Achim Steiner, head of the UN Environment Programme.
Increased tree cover in cities also works pretty well to reduce city temperatures during the summers, potentially saving on cooling costs and electricity use for the cities inhabitants.
“Recent studies highlight the importance of even small urban gardens in providing habitat for native pollinators such as bees, which have declined alarmingly in recent years,” the study added.
It’s also easy to argue for the economic benefits of adding greenery. In the United States, “city parks increase the value of nearby residential properties by an average of 5 percent; excellent parks can provide a 15 percent increase.”
And one of the most important reasons for increasing the greenery in cities is that, as urban areas expand, agricultural area is being lost, and there is going to have to be a shift in where agriculture occurs if such growth is to continue.
“For the next 40 years urban growth will consume land approximately three times the size of France … this is often the most prime agricultural land,” Elmqvist said.
Currently, there are many cities that are already taking measures to become greener. “In Bogota, Colombia, residents exercised more after city authorities introduced measures such as closing some roads on weekends and improving bus transport.”
And in Mexico City, a new “Green Roof Program” is planning to create at least 10,000 square meters (107,000 sq ft) of rooftop agriculture every year.