MARINE POLLUTION

WHY IN NEWS

• In August 2020, a Japanese bulk-carrier ship carrying fuel oil struck a coral reef resulting in an oil spill into the Indian Ocean, near the coast of Mauritius.

BACKGROUND

• Ocean pollution, also known as marine pollution, is the spreading of harmful substances such as oil, plastic, industrial and agricultural waste and chemical particles into the ocean.
• About eight million metric tons of plastic end up in the oceans every year, according to EcoWatch
• While in the 1970s there were 24 large oil spills per year, in the 2010s the average number of large oil spills decreased to 1.7 oil spills per year.

CAUSES:

• Land runoff:
  • Land-based sources (such as agricultural run-off, discharge of nutrients and pesticides and untreated sewage including plastics) account for approximately 80% of marine pollution.
• Intentional discharge
  • Toxic waste, including mercury, released by manufacturing plants enters the sea and the food chain, making its way up to larger species consumed by humans.
  • Agricultural toxins can be direct biological hazards and raise ocean temperatures, which can be deadly for some animals and plants.
• Atmospheric pollutants
  • Various types of pollutants can get in the water through rain.
  • A particular menace is carbon dioxide, which has built up with climate change. The oceans are absorbing the excess and becoming more acidic.
  • This has been particularly troublesome for calcium carbonate structures such as corals, which cannot regenerate or regrow.
• Oil spills:
  • Pollution caused by ships, is a huge source of ocean pollution, the most devastating effect of which is oil spills.
  • Crude oil lasts for years in the sea and is extremely toxic to marine life
• Ocean mining:
  • The ocean floor is a valuable source of gold, silver, copper, and zinc, but mining under the sea is a major source of pollution.
  • Sulfide deposits created when these substances are drilled can have environmental impacts.
  • Material leaks and corrosion of equipment only exacerbate the problem.
• Plastic pollution:
  • In 2006, the United Nations Environment Programme estimated that every square mile of ocean contains 46,000 pieces of floating plastic.
  • Once discarded, plastics are weathered and eroded into very small fragments known as micro-plastics.
  • Plastic materials and other litter can become concentrated in certain areas called gyres as a result of marine pollution gathered by oceanic currents.
  • For example, the North Pacific Gyre is now referred to as the Great Pacific Garbage Patch, where waste material from across the North Pacific Ocean, including coastal waters off North America and Japan, are drawn together.
• Developmental activities and tourism:
  • Coastal tourism, port and harbour developments, damming of rivers, urban development and construction, mining, fisheries, aquaculture etc., are all sources of marine pollution threatening coastal and marine habitats.
• Poor waste management system:
  • Much of the plastic that gets washed into oceans is from countries with large populations and poor waste management.
• Alien species:
  • Several thousand per day transported in ballast water; also spread through canals linking bodies of water and fishery enhancement projects.
• Noise pollution:
  • Super-tankers, other large vessels and machinery causes noise pollution >> may stress and disrupt marine life.
• Radioactive waste:
  • Discharge of radioactive substances from discarded nuclear submarine and military waste
• Rapid urbanisation along the coastlines:
  • In 2012, thirteen of the world’s 20 megacities were situated along coasts.
  • Many of these populations put pressure on infrastructure where urban waste and sewage management is poor

EFFECTS:

• Eutrophication:
  • When a water body becomes overly enriched with minerals and nutrients which induce excessive growth of algae or algal bloom. This process also results in oxygen depletion of the water body.
• Effect of toxic wastes on marine animals:
  • The long term effect on marine life can include failure in the reproductive system, behavioural changes, and even extinction of species.
• Depletes oxygen content in water:
  • Most of the debris in the ocean does not decompose and remain in the ocean for years. Due to this, oxygen levels go down, as a result, the chances of survival of marine animals also goes down.
• Formation of dead zones:
  • Excessive nutrients from sewage and agricultural runoff have contributed to the number of low oxygen (hypoxic) areas known as dead zones, where most marine life cannot survive, resulting in the collapse of some ecosystems.
  • There are now close to 500 dead zones covering more than 245,000 km² globally, equivalent to the surface of the United Kingdom.
• Effect of alien species:
  • Outcompete native species and reduce biological diversity.
  • Also they introduce new marine diseases and are associated with increased incidence of red tides and other algal blooms
• Disruption to the cycle of coral reefs:
  • Oil spill floats on the surface of the water and prevents sunlight from reaching marine plants and affects the process of photosynthesis.
• Effect on food chain:
  • Small animals ingest the discharged chemicals and are later eaten by large animals, which then affects the whole food chain.
• Affects human health:
  • Animals from impacted food chain are then eaten by humans which affects their health as toxins from these contaminated animals get deposited in the tissues of people
• Economic impacts:
  • Depletion of fishing resource >> affect huge number of people dependant on fishing sector

GLOBAL INITIATIVES:

• The Global Programme of Action (GPA) for the Protection of the Marine Environment from Land-based Activities:
  • The GPA is the only global intergovernmental mechanism directly addressing the connectivity between terrestrial, freshwater, coastal and marine ecosystems.
• International conventions:
  • MARPOL convention (1973) - It covers pollution of the marine environment by ships from operational or accidental causes.
  • The London Convention (1972) - Its objective is to promote the effective control of all sources of marine pollution and to take all practicable steps to prevent pollution of the sea by dumping of wastes and other matter.
  • UNCLOS prescribes the responsibility on the Coastal States in preserving and protecting the marine environment and associated resources
• The Bangkok Declaration on Combating Marine Debris in ASEAN Region was adopted by leaders of the 10-member Association of Southeast Asian Nations

INDIAN INITIATIVES

• India ratified Bunker Convention:
  • In 2015, India ratified the International Convention on Civil Liability for Bunker Oil Pollution Damage, 2001 (Bunker Convention)
  • Bunker convention ensures adequate, prompt, and effective compensation for damage caused by oil spills.
• The Coast Guard Act,1978
  • It states that the preservation and protection of marine environment and control of marine pollution is the function of the Indian Coast Guard
• National Oil Spill Disaster Contingency Plan (NOS-DCP)
  • Government prepared the National Oil Spill Disaster Contingency Plan (NOS-DCP) in 1993 and designated the Indian Coast Guard as the Central Coordinating Authority.
• Online Oil Spill Advisory system
  • Online Oil Spill Advisory system is established by Coast Guard in 2015.
• BEAMS (Beach Environment & Aesthetics Management Services)
  • India has launched India’s own eco-label BEAMS under ICZM (Integrated Coastal Zone Management) project.
  • It aims to abate pollution in coastal waters and protect and conserve coastal ecosystems and natural resources.

WAY FORWARD

• Limit off-shore drilling:
  • Focus on renewable energy sources, such as wind or solar power, to limit off-shore drilling.
• Encourage organic farming:
  • Limit agricultural pesticides and encourage organic farming and eco-friendly pesticide use.
• Waste water treatment:
  • Proper sewage treatment and exploration of eco-friendly wastewater treatment options.
• Reduce industrial waste:
  • Cut down on the industry and manufacturing waste and contain it into landfills to avoid spillage.
• Use of biotechnology:
  • Bioremediation (use of specific microorganisms to metabolize and remove harmful substances) to treat oil spills.
• Adopt a green lifestyle:
  • At individual level reduce carbon footprint by adopting a "green" lifestyle.
• Adopt a Montreal like global treaty  on marine pollution
  • To ensure collaborated effort to clean up the ocean.

PRACTICE QUESTION:

Q. Explain the major anthropogenic causes of marine pollution and analyse the efficacy of international efforts to control such pollution?