Summary
Highlights
This is the final part of Chapter 2 (or Chapter 5, part 5) of Environmental Management, focusing on oil pollution. The syllabus covers the impact of oil pollution on marine and coastal ecosystems, its causes (offshore oil extraction, pipelines, shipping), its effects on birds, marine mammals, coral reefs, and beaches, and the management strategies involved. It's crucial to differentiate between strategies for reducing oil spills and strategies for minimizing their impact after they occur.
Major causes of oil spills include leakage from offshore oil extraction rigs and pipelines, and shipping risks like collisions or damage to oil tankers. The impact on ecosystems starts with phytoplankton, the primary producers; oil floating on the surface blocks sunlight, preventing photosynthesis and leading to their death. This causes a food shortage for fish. Oil also prevents gas exchange, reducing oxygen in the water, which kills fish. Direct contact with oil affects fish gills and hinders movement. Birds consume toxic oil when eating fish, and oil on their feathers impairs their flight. Marine mammals face food depletion, ingest toxic oil, and their skin is affected by oil coating. Coral reefs suffer complete devastation due to lack of oxygen, as oil reduces oxygen content and covers the area.
Beaches are covered in oil, and oil washed by tides coats rocks and organisms in shallow waters and rock pools, leading to their death due to toxic effects. Oil spills also severely impact animal food sources and tourism.
Management of oil pollution involves ways to reduce oil spills in the marine environment. The MARPOL (Marine Pollution) convention sets regulations to reduce oil pollution from ships, including supervising oil transport at sea. All oil tankers must be certified to have appropriate systems, or they face heavy fines or are prevented from leaving port. Tanker design is another way to prevent spills; instead of a single hull, double hulls are advisable. If the outer hull is damaged, the inner hull prevents oil spillage.
Once an oil spill has occurred, strategies are employed to minimize its impact. Floating booms, which are barriers, surround the oil slick to prevent its spread, effective in calm seas and smaller spill areas. Detergent sprays break down oil slicks into smaller, degradable droplets, but they can damage coral reefs as corals are not tolerant to detergents. Skimmers clean the water by using materials that oil easily attaches to, dragging the oil off the seawater surface and collecting it in a container.