Climate-friendly tree plantation key to prevent heatwave: Experts

To prevent intense heatwaves and safeguard biodiversity, city planners and environmentalists have strongly recommended nature's age-old solution — a climate-friendly tree plantation campaign in urban areas.

In Dhaka, unplanned urbanisation has resulted in two major outcomes: the loss of native trees and the planting of foreign ones unsuitable for the local environment. This has degraded biodiversity and changed heatwave dynamics, said the environmentalists at a seminar titled "Climate Change and Strategies for Heatwave Prevention," hosted by the Zoom Bangladesh Youth Foundation at the National Press Club today (18 May).

"Dhaka, once adorned with trees and foliage, has now become devoid of greenery due to rampant tree cutting and the creation of artificial gardens," said Iqbal Habib, an architect and vice-president of Bangladesh Poribesh Andolon (Bapa).

"The misguided practice of planting exotic trees like acacia and eucalyptus instead of species suited to the local environment has destroyed the city's biodiversity," he said.

"If Hatirjheel could be transformed with extensive tree planting within just six years, why has not this been replicated in every city across the country?" he said, attributing the lack of urban greening to the absence of a national greening policy.

Environmental experts have identified insufficient vegetation and wetlands as contributing factors to the intense heatwave in the country.

They said heatwaves are becoming intolerable in densely populated areas with numerous high-rise buildings and factories. They pointed to several contributing factors, including excessive air conditioner (AC) usage, glass-walled buildings, and air pollution.

The seminar's main speaker, Professor Ainun Nishat, a pioneering expert in water resource management and climate change, said, "Nature is retaliating with unbearable heat and cold spills for the cruelty that humans have committed against the environment. In the coming days, these may take a more dire form and strike."

Regarding Dhaka's wetlands, architect Iqbal Habib said, "Around 33,000 squatters in the capital are holding two crore people hostages. They have occupied more than 70% of the city's canals, rivers, and water bodies, constructing multi-storied buildings, which has turned Dhaka into one of the most polluted cities in the world."

Discussing the potential for recovering the canals, he said, "If the canals cannot be reconnected to the rivers, the canal cleaning efforts by Dhaka's mayors will be futile. Consequently, Dhaka will face massive flooding in the coming days.

"If land can be acquired for ambitious development projects, then it is also possible to acquire land to address waterlogging in Dhaka city." 

Global standards suggest that around 10-12% of a city's total land area should be wetlands to ensure livability. In 1995, over 20% of Dhaka's area comprised wetlands, but this has now dwindled to less than 3%.

A study by the Bangladesh Institute of Planners (BIP) revealed that approximately 86% of the wetlands within Dhaka's two city corporation areas (excluding new wards) have been filled over the past 28 years.

Prof Dr Ahmad Kamruzzaman Majumder, founder of the Centre for Atmospheric Pollution Studies and an expert in environment and climate, said, "The increasing rate of pollution and toxic dust particles in Bangladesh's air is causing diseases to hundreds of thousands of people every year. Without a comprehensive plan to address this pollution, thousands of lives could be lost annually."

The seminar was co-hosted by Ocean Network Express, the South Asian Climate Change Journalists Forum, and the Centre for Atmospheric Pollution Studies.