Now, wetland biodiversity in Dhaaka is at critical risk

Wetlands are considered one of the most important ecosystems in the entire world. Various species of plants and animals live especially in wetlands. This swamp is their safe haven. Wetland-centered biodiversity of Dhaka city is threatened by pollution.

In addition to ecological importance, a country’s culture, heritage, social life—wetlands and wetland-based biodiversity all have an important relationship. Its economic importance is not less.

But day by day, wetlands are losing their luxuriance, loss of habitat quality and a large part of biodiversity is endangered today. Biodiversity in cities in particular is most at risk today.

The past and present situation of Dhaka shows us how endangered the urban aquatic biodiversity of Bangladesh is. If conservation initiatives are not taken in the rest of the cities, they will also face the same situation.

Dhaka, currently the capital of Bangladesh, began its journey in the early 17th century. At that time, Dhaka was full of diversity of natural wetlands. The city was full of greenery. It is difficult to live in Dhaka now.

According to the United Nations World Urbanization Prospects, Dhaka’s population will reach 2.74 million by 2030. From the current 11th most populous city, it will become the sixth most populous city in the world.

Increasing population leads to more waste and pollution, causing concrete to lose its natural aesthetics and richness.

Dhaka is located in the Jamuna-Brahmaputra floodplain, one of the 22 bio-ecological areas of Bangladesh, which used to have a lot of wetland-focused natural resources and biodiversity. In the beginning, apart from some settlements on the banks of the Buriganga, Mirpur, Paltan, Tejgaon, Kurmitola in the north of Dhaka were huge forests and its Kamrangirchar in the south had huge forests, the rest of the areas were basically water bodies. And around them were the settlements of various wild animals, which are only in the pages of books today.

Many different animals, such as tigers, giant pythons, wild boars, wild cats, and fishing cats, were seen moving in Dhaka and its surrounding areas. Even 50 years ago, Dhaka was a wonderful canvas composed of swamps, forests, grasslands rather than human habitations, offices, shops and roads.

According to various information, at that time wild animals were roaming in the busy areas of present Dhaka. They enjoyed unrestricted freedom of movement. The call of the fox could also be heard from the thorn forest.

Once the habitat of native peafowl, red goose, met pheasant, black pheasant, has now turned into a pile of bricks and garbage.

Wild ducks and cranes have died, and water bodies have turned into stagnant ponds, becoming breeding grounds for infectious diseases. By destroying nature, man has created his own death coffin. Nature is losing its balance.

Research from 2010 and satellite images reveal that in 1960, Dhaka had 2,952 hectares of wetlands and 13,527 hectares of lowlands. By 2008, these numbers decreased to 1,990 hectares and 6,414 hectares, respectively.

A report by the Institute of Water Modeling (IWM) shows that over 10,000 hectares of wetlands, canals, and lowlands in Dhaka have disappeared since 1985. Even in 1995, more than 20 percent of the total area of ​​Dhaka city was wetlands. A city needs to have 10 to 15 percent water bodies of its total area. But only 3 percent survive in Dhaka now.

The groundwater level in Dhaka has been decreasing over the years. In 1996, it was 25 meters below ground level. By 2005, it had dropped to 45 meters, and by 2010, it had reached 60 meters.

As of 2024, the groundwater level has declined even further to 86 meters below ground level, according to the Bangladesh Water Development Board.

Every year the underground water level of Dhaka is going down by two to three meters. On the other hand, to ensure livability, 15 percent of the city’s total land must be covered with greenery. Dhaka city now has only 9 percent. And the reservoirs that currently exist in Dhaka, are their natural environment and quality right? The answer is, no. Due to continuous pollution, most water bodies are now toxic.

Changes in water regulators like dissolved oxygen and carbon dioxide have caused significant changes in aquatic environments and how they are managed. So there is a shift from the producer to the highest consumer level.

A huge change has taken place in the food chain. Some reservoirs have water but lack organism diversity. No birds, no mammals, reptiles or amphibians.

In simple words, in the coming days, nobody will never be able to stay outside in this intense heat and heat wave, none will find a place that is convenient for them and have a favorable environment for living. And that is what happened with this biodiversity. This is why the water body biodiversity has been continuously lost from Dhaka.

However, it must be remembered that humans can never artificially improve the natural environment. By destroying the natural environment of the wetlands, by adding concrete to enhance their beauty, humans will never be able to complete the natural biochemical processes, which are happening all the time now.

Absence of a small regulator of the environment is causing catastrophe. Therefore, in the name of beautification, we must refrain from destroying the aquatic environment. Man should understand that he does not have the power to control nature.

Similarly, we need to give importance to the preservation of aquatic biodiversity in cities outside Dhaka. Environmental assessment of any project is very important.

It is never possible to keep the aquatic environment healthy by planting trees causing great disaster to the aquatic environment. We need to make people more aware at the policymaking level. Conservation of aquatic biodiversity is the need of the hour today to avoid major disasters for temporary benefits.