The vegetation in urban open spaces act as a sink for carbon dioxide. They reduce pollution and produce oxygen. They allow rain water percolation and ground water recharge in addition to facilitating storm water drainage and flood attenuation.
Other advantages provided by them to human societies include social and psychological benefits, recreation, better health, reduced stress levels and reduced depression. The air we breathe and the water we drink are the two primary elements which decide the quality of our life. Thus when the open spaces shrink the quality of life of the people also degrade. There are studies proving that people who use public open spaces enhance their physical activity and gain better physical and mental health benefits, reducing healthcare costs.
Urban vegetations in the tropical region are estimated to absorb 200-300 tonnes of carbon per hectare per year and provide a huge potential for climate change related mitigation benefits. Trees in cities help fight global warming by reducing the amount of greenhouse gases in the atmosphere and help to cool cities.
Parks also help create human and energy efficient cities that can help slow global warming. Thus urban landscapes are to be considered for their intangible benefits than tangible or commercial benefits.
Urban greenery contributes towards a city's economy. They attract tourism and better prices for residential and commercial properties. It is a win-win situation for the authorities and citizens in creating and maintaining urban greenery. Therefore, more attention is needed to develop urban green spaces by involving NGOs and resident welfare associations.
Considering the fast pace of urbanisation in India with an estimated 241 million people in working age population supposed to seek shelter in cities in search of job opportunities and investments by 2030, enhancement of urban green spaces are one of the ways, to mitigate the adverse effects of urbanisation in a sustainable manner.
Urban green space:
Cities globally acclaimed for their urban green spaces, often have a per capita urban green space of 20 to 40% of the total geographical area. The scientifically suggested green area per capita is more than 20 m2 which is equivalent to a minimum of 1.25 ha open space per 1,000 residents.
Indian cities like Gandhinagar and Chandigarh, where the urban greenery was pre-integrated in the city master plans at the initial design phase itself have per capita green space at 160 m2 and 55 m2 respectively. It is far more as compared to traditional green cities like Bengaluru.