Font size:
Print
Marine Pollution
Context:
Until recently, it was assumed that the vastness of the oceans could absorb any amount of waste without harm. However, the massive dead zone in the Gulf of Mexico and the extensive plastic belt in the Pacific Ocean now reveal the catastrophic impact of this misconception on marine ecosystems.
Overview of Marine Pollution:
- Marine pollution, encompassing a wide array of pollutants from plastics to chemicals, is a significant threat to marine ecosystems and human health.
- This issue has escalated over the years due to various factors, leading to severe consequences for both the environment and biodiversity.
- Practices like bottom trawling worsen the issue by damaging habitats and increasing bycatch, highlighting the need for stronger waste management and regulatory measures to protect ocean health.
Types of Marine Pollution:
- Chemical Pollution: Harmful chemicals like pesticides, herbicides, fertilisers, and industrial waste enter oceans, often through land runoff or direct discharge, causing toxic effects on marine life and ecosystems.
- Plastic Pollution: Plastics, especially single-use items, are a major pollutant.
- They do not biodegrade easily and can persist in the environment for centuries, harming marine animals that ingest or become entangled in them.
- Noise Pollution: Increased underwater noise from ships, oil rigs, and sonar disrupts marine life, particularly mammals like whales and dolphins, by interfering with their communication, navigation, and hunting behaviours.
- Light Pollution: Artificial light affects marine organisms, particularly those in shallow waters, by disrupting natural behaviours such as feeding, breeding, and migration.
Causes of Marine Pollution:
- Land Runoff: Pollutants from agricultural and urban areas are carried into the ocean by rainwater and melted snow, bringing toxic chemicals, oils, and other pollutants.
- Intentional Discharge: Industries sometimes discharge waste, including hazardous chemicals, directly into the ocean.
- Oil Spills: Oil spills can have devastating impacts on marine ecosystems, as evidenced by the Deepwater Horizon disaster in the Gulf of Mexico in 2010.
- This was one of the largest oil spills in history, releasing approximately 134 million gallons of crude oil into the ocean over several months.
- Littering and Atmospheric Pollution: Trash, particularly plastics, enters the ocean through littering and atmospheric deposition, contributing to the massive accumulation of debris in ocean gyres.
Impact of Marine Pollution:
- Loss of Biodiversity: Pollution can cause direct mortality in marine species, disrupt reproductive cycles, and lead to long-term population declines.
- Damage to Coral Reefs: Coral reefs are highly sensitive to pollutants.
- About 50% of the world’s coral reefs have died in the last 30 years due to pollution, climate change, and other stressors.
- Bioaccumulation: Toxic substances accumulate in marine organisms, moving up the food chain and posing health risks to humans who consume seafood.
- The Minamata disaster in Japan in the 1950s is a tragic example of the consequences of mercury bioaccumulation.
- Ocean Acidification: Increased CO2 emissions lead to acidification, harming shell-building organisms and disrupting marine ecosystems.
Counter Strategies:
- Stricter Laws and Regulations: Enforcing regulations against illegal dumping and improving wastewater treatment can reduce direct pollution.
- Promoting Sustainable Practices: Encouraging sustainable agriculture and industrial practices can minimise runoff and reduce the introduction of pollutants into the ocean.
- Recycling and Waste Reduction: Reducing single-use plastics and promoting recycling are crucial for decreasing ocean plastic waste, a key focus of initiatives like India’s O-SMART program.
- Launched in August 2018, O-SMART emphasises ocean research, early warning systems, and monitoring coastal water quality.
- Public Education and Awareness: Raising awareness about the impacts of marine pollution and promoting responsible consumer behaviour can contribute to long-term solutions.
International and National Initiatives:
- UNEP Initiatives: The United Nations Environment Programme (UNEP) runs campaigns like Clean Seas to combat marine plastic pollution and protect marine environments globally.
- India’s Efforts: India has implemented measures like the “Swachh Sagar Abhiyan” and adheres to international conventions like MARPOL to address marine pollution along its extensive coastline.
