Ocean pollution is taking terrible forms
Sea is one of the sources of energy and resources. People's dependence on the sea is also increasing. But the seas of the world are losing their shape day by day due to various types of pollution. The main things that pollute sea are airborne dust, waste from tankers and other ships, various plastic wastes, polythene etc. The pollutants released into the atmosphere fall directly into the sea due to rainfall. As a result, the sea becomes a wasteland.
With increasing number of industry, the amount of carbon dioxide in the atmosphere is increasing due to the burning of various fossil fuels. Such pollution increases the acidity of seawater and harms marine animals and plants. In addition, global warming is causing sea levels to rise and the amount of oxygen in the water to decrease. Various diseases are also spreading among marine animals.
A report has been published on the basis of the latest research on how climate change is changing the environment of the oceans and affecting the livelihoods of marine animals. William Cheung, a professor at the University of British Columbia in Canada, said climate change will have an impact on all marine animal and plant species and resources. The oil is so thick that it evaporates and mixes with the water without sinking. As a result, harmful hydrocarbons such as toluene and benzene easily enter the food chain, poisoning everything from tiny zooplankton to large mammals, and the effects of this pollution are far-reaching.
According to a report, 90 per cent of marine animals die from the filters used to clean oil. In Japan in the sixties, many people became paralyzed by eating mercury-carrying fish, and there were cases of damage caused by fires in the oil floating in the sea. Industrialized toxins, household waste, artificial filters, fertilizers and pesticides are responsible for this terrible condition of sea. Moreover, there is oil pollution.
Plastics are also one of the main culprits in marine pollution. According to the United Nations, at least 800 species worldwide have been affected by marine debris, and 80 per cent of this debris is plastic. It is estimated that 13 million metric tons of plastic are deposited in the ocean each year, equivalent to the load of a garbage truck per minute.
Marine fish, birds, turtles, and mammals may become entangled in or infected with plastic debris, causing them to suffocate and eventually die from starvation. According to a recent study, about 90 per cent of seabirds are directly exposed to plastic pollution. Oceans cover 90 per cent of the world's habitable habitat. The global average temperature needs to be effectively controlled to prevent the worst effects of climate change in this vast space. And the governments of different countries have to work together to limit the average temperature rise to a maximum of two degrees.
The future of the oceans will depend on how much carbon is emitted in the coming decades. Carbon dioxide emissions must be reduced immediately if we want to prevent irreparable damage to the ocean's overall environment. If global warming is not controlled, there will be irreparable damage to the animals and plants living in the oceans. Marine fish will be forced to look for relatively cold water. Valuable atolls will be destroyed. Scientists have given these warnings in an international study published in the journal Science.
Besides, petroleum production is increasing all over the world. Therefore, there are many reports of large pipelines collapsing for its import and export by sea. Sometimes oil can be extracted from coastal oil mines due to geological reasons. According to one study, about one million metric tons of oil falls into the sea each year during transportation alone. In addition, more than 1.5 million tonnes fell from coastal oil mines or similar production.
Hydrocarbons leaking from underground levels are normal. Refining, industrial use, import-export, tanker sinking, coastal oil mines, etc are disasterous to oceans. Apart from oil, other mineral resources in the sea include sand, gravel, heavy minerals and deep sea manganese gravel. Dredging and passing sand, gravel, etc along the coast often cause damage to marine life.
Geological and meteorological factors influence sea level rise. It is estimated that the sea level has dropped a lot due to the collapse of the mountains at the bottom of the sea. For centuries people have been harming environment by returning carbon, known as 'fossil fuel', to the atmosphere.
Among the toxins emitted, copper, nickel, cobalt and manganese are generally very harmful to environment. Insecticides, DDT and chlorine used in various types of insulation are harmful to the sea. DDT is widely used to kill crops, insects, spiders and flies all over the world. Rainwater is washed away and eventually deposited in the sea. Much of the radiation released by nuclear tests into the air is released into the oceans.
At present, animals are facing restriction to safe movement in the sea. A few days ago, two dead whales float in Bangladesh's sea coast. That is alarming for ocean diversity and environment.
All our rivers have ended their journey at sea. At the end of the day, the waste flowing through these rivers is deposited in all the seas. But this sea meets most of our needs. On the other hand, the entire trade of Bangladesh is dependent on the Bay of Bengal. So we have no choice but to protect our precious resources. For this, strict implementation of Waste Management Act, Maritime Transport and Tourism and Marine Resources Act has to be formulated and enacted.
The writer is associate editor, The Environment Review