The case for urban trees: Greenery can improve public health in Karachi

Doctors and environmentalists agree trees boost physical and mental wellbeing

KARACHI: Since 1984, when researcher Roger Ulrich discovered that patients with greener views recovered more quickly than others, there has been growing scientific evidence in support of the health benefits of trees. In Karachi where trees are at the mercy of greedy civic agencies and advertisers, there’s an urgent need to understand the link between public health and the city’s green cover and protect the urban lungs.

Syed Zafar Ahmed Fatmi, an associate professor at Aga Khan University Hospital’s Department of Community Health Sciences, says urban trees - with their shade and cooling effect - decrease the overall temperature and prevent formation of heat islands in the city so much so that a house can have 30% decrease in energy-use by having two to three fully grown trees around it.

“In Karachi, where many people work outdoors, exposure to heat can have negative health effects. Contact with heat causes electrolyte misbalance - fluctuation of fluids in our body due to deficiency or overabundance of essential minerals - and trees reduce chances for this as well as of heat exhaustion and heat stroke,” the associate professor explains.

Fatmi says people living in greener areas are also more inclined to do physical activities which in turn affect their fitness. “More trees mean you go out for walk and you walk more. With few trees, there’s smoke, dust and heat in the environment and people are unlikely to go out if not necessary,” he says.

Further listing the benefits, Fatmi says trees absorb carbon dioxide and other pollutants and as a result make air cleaner to breathe.

Peace of mind

Explaining how trees affect our mind, psychologist Naheed Khan says the soothing effect of lush green trees helps to stay calm. “Interacting with vegetation like in gardening is also therapeutic as seeing something grow enhances mental health,” she states.

Khan says the green colour of urban trees is pleasing to human eyes in contrast to grey concrete. “When we go to big cities like New York, we may marvel at architectural wonders but tall buildings are not as pleasing as tall trees,” she remarks, stating that tree shade is precious as it refreshes our body even during hot days.

The sound of wind going through tree leaves, Khan adds, brings peace of mind.

The psychologist believes cutting down trees may lead to increase in mental problems. “Driving on a road with no or less trees increases the chances of road rage. Tall green trees can be a soothing distraction from hectic traffic jams,” Khan says.

Trees also reduce stress and Khan says in some cases that can prevent high blood pressure.

City life

Urban planner and member of NGO Shehri-CBE Farhan Anwar says parks and public spaces dotted with trees serve as spaces where urban residents find respite from the stresses and strains of life. “Such spaces also serve in building social capital - networks of relationships among people - as residents gather and integrate thus having a beneficial impact on their health and wellbeing,” he adds.

Muhammad Naeem Qureshi, president of National Forum for Environment and Health, says trees also help maintain the ecological balance of urban environments which are constantly harmed by human activities, cars and industries.



“Around 70% of the pollution in the city is coming from the transport sector but we don’t have enough trees to save ourselves from these harmful effects. We need this natural protective shield to live,” he stresses.

How trees make us healthier?

Looking at trees or being around them reduces stress, lowers blood pressure and improves mood: Numerous studies show that both exercising in forests and simply sitting, looking at the trees reduces blood pressure as well as stress-related hormones.

Spending time in nature helps you focus: Being amidst nature gives the cognitive portion of our brain a break, allowing us to focus better and renew our ability to be patient.

Natural outdoor environments help children pay attention and control impulses: Studies show children who spend time in nature have a reduction in attention fatigue and children diagnosed with ADHD show a reduction in related symptoms.

Patients recover from surgery faster and better when they have a “green” view: A research found that patients with “green” window views had shorter postoperative stays, took fewer painkillers, and had slightly fewer postsurgical complications compared to those who had no view or a view of a cement wall.

Exposure to trees boosts our immune system: Certain plants give off chemicals to protect themselves from insects. When we breathe in these chemicals, our bodies respond by increasing the number and activity of a type of white blood cell called natural killer cells which kill tumor- and virus-infected cells in our bodies.

SOURCE: NEW YORK STATE DEPARTMENT OF ENVIRONMENTAL

CONSERVATION WEBSITE

Published in The Express Tribune, July 13^th, 2016.