Marine Pollution in the Indian Ocean: An alarming bell
The Indian Ocean is the third largest ocean on earth, covering about 20 per cent of the earth's water surface. It expands to South Asia in the north, Africa and Arabia in the west, South East Asia and Australia in the east, and Antarctica towards the south. It hosts a vast flora and fauna, with 9 of the 36 biodiversity hotspots located at the Indian Ocean, including Madagascar. The Indian Ocean also boasts of covering half of the world’s mangrove habitat, a majority of which is located in Indonesia. It supports a variety of marine life, with some of the largest concentrations of phytoplankton blooms happening in the western Indian Ocean.
Close to forty countries are dependent on it for economic, military and commercial use. The Indian Ocean is surrounded by some of the world’s most densely populated nations, India being the highest, with a population of 1.3 billion. The region around this ocean, geographically and culturally, is exceptionally diverse.
Like almost every other water body on earth, the Indian Ocean is also immune to an alarming level of marine pollution. Marine pollution is described as the contamination of water bodies caused by waste generated by human activities. It poses a severe threat to aquatic life, which is an essential component of the food chain. The primary sources of marine pollution in the Indian Ocean are chemicals, oil spillage and plastic.
Chemical Pollution
Chemical pollution is caused due to the entry of harmful chemicals into the water bodies. The major source of these artificial components is fertilizers, pesticides and herbicides, household products like detergents, chemicals used by the pharmaceutical industry, beauty products, and sewage. Most countries around the Indian Ocean are developing countries largely dependent on agriculture and in a transitionary phase with rapid industrial development with little regulation. Urbanization is happening at a fast pace but is unplanned and unregulated in many cases. There is widespread use of fertilizers which wash up with the rainwater and enter the nearby water bodies like estuaries, streams or rivers which eventually join the ocean. Coal burning is common in industries and households in the Indian Ocean region, as a large proportion of the population is still using this primitive energy source. Coal contains a harmful substance called mercury. When it is burned, the mercury vaporizes and enters the atmosphere, landing in the oceans. The dumping of untreated sewage and radioactive materials generated during mining is also very harmful marine pollutants. Chemical pollution leads to a phenomenon called algal bloom. Phytoplankton is a photosynthesizing alga that uses nutrients like nitrogen and phosphorus, which become present in excess due to chemical pollutants present in the ocean. The algae cover a large surface of the water, which blocks sunlight from reaching the ocean floors and causes a severe reduction in the oxygen level of water. This event creates dead zones in the ocean bodies, where the survival of marine organisms is difficult. A dead zone of an estimated was found in the Bay of Bengal, located in the northeastern Indian Ocean. In the past 25 years, algal bloom spread caused an estimated loss of $100 million a year in the Indian Ocean RIM countries.
Oil Pollution
The Indian Ocean region accounts for around 40% of the world's off-shore oil production. The Persian Gulf, also a part of the Indian Ocean region, is the highest oil-producing region of the world. Certain dangerous events like oil spills are tremendously damaging for the oceans. Oil spills can occur for various reasons, like accidental leaks and careless release of oil and its products in the water bodies. Illegal discharges shipping operations are other contributing factors. Oil spills can have a deadly effect on aquatic life and marine birds as it contains highly toxic residual matter. In 2020, a Japanese vessel, MV Wakashio, hit a coral reef on the southern coast of Mauritius in the Indian Ocean and went aground. The disaster happened at a biodiversity hotspot home to a staggering 1,700 marine species. Since this event, more than 50 whales and dolphins have washed ashore, numerous people have lost their livelihoods and there has been a significant setback in the tourism industry of Mauritius. The pristine coral reefs of the island nation will be largely affected due to coral bleaching, impacting their reproduction, growth and development and destroying the coral population. Oil inputs include volatile substances released into the atmosphere when burned, which then enter the water. Pollution through the atmosphere and industrial and municipal effluents are tainting the Indian Ocean in significant ways.
Plastic Pollution
Plastics account for 80% of all litter in the oceans. This waste is especially generated because of single-use plastics such as wrappers, shopping bags, disposable plastic bottles, and caps. A large percentage of plastic waste is predicted to enter the Indian Ocean. Most of the countries (Indonesia, Thailand, Malaysia, India and Bangladesh) contributing to the highest amount of plastic pollution worldwide are located in the Indian Ocean region. Two of the world's largest and most polluting rivers- the Ganges and the Indus also flow into the Indian Ocean. There can be two types of plastic materials- one whose weight is heavier than seawater and can sink into the ocean bed, the second which is lighter in weight and floats on water. It has the potential of traveling huge distances and can accumulate into large patches of waste covering the ocean. Plastic waste in the Indian Ocean is known to occur from land-based, ocean-based and coastal sources. As much as 15% of the global plastic waste has entered the ocean through coastal sources. Billions of plastic material is dumped into the Indian Ocean each year. In a remote island off the coast of Australia, 414 million pieces of plastic pollution were uncovered, out of which 380 million were found buried in the sand. One main reason for this is the poor waste management across the region and a general lack of funds to build efficient waste disposal facilities.
Aquatic animals have consumed many microplastics, as a lot of accumulated plastic has been found in their bodies that wash up the shore. In a recent event in what is deemed as Sri Lanka's "worst maritime disaster," a container ship caught fire and sank in the Indian Ocean. The most significant damage came from the spillage of 1680 tonnes of nurdles, which are small plastic pellets used for making most of the plastic products we use. They are often mistaken as food by fish, seabirds and other organisms. Nurdles are the second-largest source of micropollutants in the ocean, following tire dust. Almost 500 turtles, 46 dolphins, and eight whales are thought to have been killed in this incident. Microplastics are one of the most toxic forms of ocean pollutants. Yet, the International Maritime Organization still does not recognize nurdles as hazardous substances.
What Can Be Done?
Even though there are many international laws and regulations that forbid the dumping of harmful substances in oceans, enforcing them is an enormous challenge. Besides controlling the current and future pollution sources, dealing with the vast pile of pollutants already dumped is another major issue. Chemical pollutants are especially difficult to entirely remove from the ocean bodies as they encroach upon the food chain and increase in concentration. Even plastics take hundreds of years to break down. In order to reduce the growing pollution in the Indian Oceans, the region's governments should invest in building improved waste disposal facilities. Frequent inspection drives in industries should be conducted, and stringent measures should be taken against those flunking the rules. Regional governments should cooperate to clean the Indian Ocean and share waste disposal technologies. Efforts should be made to create a Blue Economy throughout the coasts of the Indian Ocean, where there is sustainable economic development, eco-tourism, use of renewable energy, and responsible maritime transport. Lastly, the region should inspire a change in consumer habits, promote reusing, recycling and reducing polluting products, practice sustainable consumerism, and do everything to save the environment.
References
1. Chemical Pollution. (n.d.). Big Blue Ocean Cleanup. https://www.bigblueoceancleanup.org/chemical-pollution
2. Howard, J. (2021, May 3). Marine pollution, explained. National Geographic. https://www.nationalgeographic.com/environment/article/critical-issues-marine-pollution
3. Jaishankar, D. (2018, August 10). Indian Ocean region: A pivot for India’s growth. Brookings. https://www.brookings.edu/opinions/indian-ocean-region-a-pivot-for-indias-growth/
4. Khadka, B. N. S. (2020, August 13). Why the Mauritius oil spill is so serious. BBC News. https://www.bbc.com/news/world-africa-53754751
5. Laurette, B., Valayden, R., Steele, M., & Takada, H. (2021, August 5). Remembering Mauritius’s worst environmental disaster. Greenpeace International. https://www.greenpeace.org/international/story/49085/mauritius-worst-environmental-disaster-one-year-on/
6. Lorenz, A. (2020, June 17). Ocean Oil Spills and its Impact. FairPlanet. https://www.fairplanet.org/story/ocean-oil-spills-and-its-impact/
7. McVeigh, K. (2021, November 29). Nurdles: the worst toxic waste you’ve probably never heard of. The Guardian. https://www.theguardian.com/environment/2021/nov/29/nurdles-plastic-pellets-environmental-ocean-spills-toxic-waste-not-classified-hazardous
8. Oil pollution of marine habitats. (2010). World Ocean Review. https://worldoceanreview.com/en/wor-1/pollution/oil/
9. Pattiaratchi, C. (2022, January 4). Plastics in the Indian Ocean – sources, transport, distribution, and impacts. 1. https://os.copernicus.org/articles/18/1/2022/
10. Qasim, S. Z. (1998). Glimpses of the Indian Ocean. University Press (India) Limited.
Pic Courtesy-Med J at unsplash.com
(The views expressed are those of the author and do not represent views of CESCUBE.)
