Fast urbanization is increasingly not tolerated. Towels, high -rise buildings, concrete walls and growing vehicle use increase the urban heat islands, whereby the city temperatures increase significantly compared to rural areas. The dependence on air conditioning systems worsens the problem, while climate change is further under pressure.
Recydration experts said that roof gardens could offer an effective solution. Studies worldwide show that green roofs reduce temperatures that improve air quality, save energy and even produce food. In Bologna, Italy, the researchers found that urban roof gardens were able to absorb 624 tons of carbon dioxide annually. In Kathmandu, Nepal, 250 families have grown half of their vegetable requirement on roofs and at the same time reduced CO2 emissions by 110 tons per year. Japan's 14-story Acros Fukuoka building, covered with 35,000 plants, absorbs 4.5 tons of carbon annually, reduces the cooling costs by 30 to 40 percent and stores 1.8 million liters of rainwater.
Dhaka, which is one of the most dirty cities in the world, is also overheating. Tree insurance fell from over 21 percent in 1980 to only 11.6 percent. The residents have only 3.5 square meters of green per person, among the WHO-recommended 9 square meters. Experts warn that the city's life capability is endangered.
Ahsan Rony, founder of Green Savers, said that the roof gardens in 450,000 new buildings are possible, although only 3-4 percent of gardens are currently planned.
“If roofs were green, heat, pollution, carbon emissions and electricity consumption, oxygen would increase,” he said. A lack of interest, disputes in common buildings and poor maintenance, however, remain obstacles, ”he added.
Studies show that green roofs can reduce the neighborhood temperatures by up to 7 ° C and keep significant rainwater, which relieves the drainage pressure. Experts ask the government to change building regulations, offer subsidies and tax exemptions and to promote the municipality on the Dach Garden in order to combat the Dhaka climate crisis.
BD Pratidine/GR