Brian Barton
Marine pollution is a pressing issue that has degraded the quality of our oceans and led to the extinction and endangerment of many marine species. There are various types of marine pollution, with plastic constituting the largest cause. Around eight million tonnes of plastic waste enter our oceans each year, with plastic debris expected to outnumber fish in the oceans by 2050 if this continues. Plastic pollution ranges from large items like bottles and bags to microplastics formed from fragmented plastic materials. Marine debris, mainly discarded human rubbish, is another significant contributor to marine pollution, with oil spills and chemical pollutants also having detrimental effects. Other types of marine pollution include nutrient pollution, toxins, noise pollution, and agricultural runoff. Light pollution, while often overlooked, also disrupts the physiological behaviours of marine wildlife. The impacts of marine pollution are far-reaching, with approximately 100 million marine animals losing their lives annually and the creation of dead zones where oxygen levels are too low to sustain life.
| Characteristics | Values |
|---|---|
| Plastic pollution | Plastic debris is predicted to outnumber fish in the oceans by 2050 if dumping continues at the current rate. The Great Pacific Garbage Patch is twice the size of Texas and contains 1.8 trillion pieces of plastic. |
| Nutrient pollution | Excess nutrients, usually nitrogen and phosphorus, enter bodies of water and act as fertilisers. This causes high levels of algae growth, restricting sunlight and oxygen and creating "dead zones" for marine life. There are currently 415 dead zones around the world. |
| Light pollution | Artificial light from coastal towns and cities can disrupt the physiological behaviours of marine wildlife, impacting migration, reproduction and feeding patterns. |
| Noise pollution | Noise from human activity travels further and longer underwater than in the air. It can confuse animals that depend on sonar signals, shorten their lifespans and threaten their existence. |
| Industrial pollution | Any waste generated from industry, including factory runoff, chemical contamination, acids, alkaline, scrap metals, sludge and coal ash. |
| Chemical pollution | Crude oil, petroleum products, pesticides, pharmaceuticals, personal care products and heavy metals are among the chemical pollutants entering the ocean. |
| Oil spills | Oil spills are a significant source of marine pollution, with around 25,000 tonnes of oil spilled in 2015. |
Explore related products
What You'll Learn
Plastic pollution
One of the main issues with plastic pollution is the ingestion of plastic by marine animals. Seabirds, sea turtles, seals, and other marine mammals often mistake plastic debris for food, leading to intestinal injuries and even death. For example, research has shown that approximately 98% of albatross chicks sampled contained plastic, and the quantity ingested was increasing over time. Additionally, plastic debris can entangle marine animals, leading to injury and mortality. Endangered species such as Hawaiian monk seals and Pacific loggerhead sea turtles are among the nearly 700 species affected by plastic entanglement and ingestion.
Microplastics, plastic particles smaller than 5 mm, are another critical aspect of plastic pollution. These tiny particles are ingested by small organisms, which are then eaten by larger animals, causing toxic chemicals to migrate up the food chain and eventually end up in the human food chain. Microplastics have been detected in various marine species, including plankton and whales, and have been found to accumulate in ocean gyres, forming large patches of plastic debris. The Great Pacific Garbage Patch, located between California and Hawaii, is one of the most well-known examples of these plastic accumulations.
The sources of plastic pollution are primarily land-based and sea-based, with plastic debris coming from a variety of human activities. Single-use plastic packaging, consumer goods, and clothing are significant contributors to plastic pollution. While some countries have enacted regulations to limit or ban disposable plastic items, more needs to be done to address the root causes of plastic pollution and promote sustainable alternatives. Preventing plastic pollution requires a combination of public education, proper waste management, and reduced consumption of disposable products.
Corporate Action: The Pollution Reality
You may want to see also
Explore related products
Nutrient pollution
The excess nutrients cause high levels of algae growth, which blocks sunlight and oxygen from entering the water, both of which are essential for nurturing aquatic plants. This leads to the decay of plants, further lowering the oxygen levels in the water and creating "dead zones" where marine life cannot survive. There are currently 415 dead zones around the world, with the largest one located in the Arabian Sea, covering an area of 165,000 square kilometers.
While agriculture is the leading source of nutrient pollution in some regions, such as the United States and the European Union, urban wastewater is often the primary source in other parts of the world, including South America, Asia, and Africa. Non-agricultural sources of excess nitrogen and phosphorus include stormwater, wastewater, fossil fuel burning, aquaculture, and domestic waste.
To address nutrient pollution, it is important to monitor it on a global scale and reduce nutrient inputs into coastal marine ecosystems. This involves implementing ecosystem management plans that consider both watershed areas on land and the seawater they drain into. Restoring habitats, such as mangroves and marshes, can also help remove nutrients from water before they reach the sea.
How Desertification Impacts Our Resources and Wildlife
You may want to see also
Explore related products
Industrial pollution
Marine pollution is defined by the 1982 UN Convention on the Law of the Sea as "the introduction by man, directly or indirectly, of substances or energy into the marine environment ... which results or is likely to result in such deleterious effects as harm to living resources and marine life."
Inland mining for minerals such as copper and gold is another source of industrial pollution. Mining has a poor environmental track record, contaminating portions of the headwaters of over 40% of watersheds in the western continental US, according to the United States Environmental Protection Agency. Some of the minerals discharged during mining can cause problems, such as copper, which can interfere with the life history and development of coral polyps.
PFAS (per- and polyfluoroalkyl substances) are human-made chemicals that are resistant to biodegradation and have been found in ground, surface, and drinking water. PFAS have been shown to significantly inhibit the growth of phytoplankton over time and accumulate in seals, polar bears, and dolphins.
The Big Apple's Pollution Problem
You may want to see also
Explore related products
Light pollution
One of the most well-known examples of the impact of light pollution on marine life is the case of sea turtles. Artificial light deters female sea turtles from coming ashore to lay their eggs, as they seek dark and quiet locations. Additionally, hatchlings are drawn towards inland lights instead of the moonlight on the water, leading to dehydration or starvation. Sea turtles are not the only ones affected; light pollution has been shown to cause massive mortality events among seabird fledglings, impacting over 70 species, some of which are already endangered.
Coral reefs, which are essential for providing food and shelter to many marine creatures, are also negatively impacted by light pollution. Corals rely on the lunar light cycle to release their sperm and eggs into the ocean for reproduction. However, light pollution can disrupt this natural cycle, causing unsynchronized spawning and reduced reproductive success, threatening the health and sustainability of coral ecosystems.
The widespread adoption of LED lighting further exacerbates the problem, as LEDs produce light with shorter wavelengths that penetrate deeper into the water. This penetration interferes with the natural cycles and behaviours of marine organisms, including migration, reproduction, and feeding patterns. For instance, clownfish eggs failed to hatch when exposed to artificial light in a study.
Efforts to mitigate light pollution are crucial to protect marine environments. Some suggested measures include enforcing ordinances that require residents in coastal areas to turn off beach-facing lights at night, implementing environmentally friendly lighting systems, adopting automatic lighting systems to minimise unnecessary lighting, and erecting coastal barriers to contain light pollution. Additionally, increasing the use of red light is recommended as it does not penetrate as far into the water, and creating Dark Sky Reserves near sensitive habitats like coral reefs can help restore natural light cycles. Addressing light pollution is vital to ensure the health and resilience of marine ecosystems and the diverse species that depend on them.
Industrial Revolution: Factories and Pollution
You may want to see also
Explore related products
Noise pollution
Marine mammals and other aquatic animals have evolved over millions of years to use underwater sound as a primary means of communicating and assessing their environment. Visibility is often low underwater, but sound is transmitted extremely well through water. Marine mammals like whales, dolphins, and porpoises rely on sound to communicate, locate mates and prey, avoid predators, navigate, and defend their territories.
To reduce noise pollution in marine environments, policies and quieter technologies are needed to mitigate propeller noise from ships, sonar equipment, seismic air guns, pile driving, and construction. Addressing noise pollution can improve the ocean soundscape and potentially enable the recovery of some marine life.
Human Activities: Groundwater Contamination
You may want to see also
