Oceans pollution

All serious cases of ocean pollution are associated with oil. As a result of the widespread practice of washing tanker holds in the ocean, from 8 to 20 million barrels of oil are deliberately dumped annually. Previously, such violations often went unpunished, but today satellites allow you to collect the necessary evidence and bring the perpetrators to justice. Special attention is required to the problem of contamination of bottom sediments by oil and oil products. In case of accidents of more than 1000 tons at shallow depths, oil products quickly reach the bottom. In temperate precipitation, the effects of oil spills can be traced for more than 9 months. In arctic conditions, oil lasts much longer.

Major Tanker Wrecks

• The wreck of the Torrey Canyon tanker in March 1967 near the Lands End in the UK . According to estimates, then about 106 thousand tons of oil fell into the sea.

• The wreck of the Amoco Cadiz tanker on the Breton coast of France in 1978, which occurred due to a tanker engine failure resulting in a crash on a rocky shore. Thousands of migratory birds died.

• In 1989, the Exxon Valdez tanker ran aground in the Alaska area and the oil spill as a result of the spill of almost 11 million gallons (approx. 50 thousand tons) of oil stretched for 1,600 km along the coast. In the criminal liability case alone, the court ordered the owner of the ship, the Exxon Mobil oil company, to pay Alaska 150 million dollars, the largest environmental fine in history. Of this amount, the court forgave the company 125 million in recognition of its participation in the aftermath of the disaster, but Exxon paid another 100 million for damage to nature and 900 million for 10 years in civil lawsuits. Although the last payment to the federal and Alaskan authorities took place in September 2001, before 2006 the government could have filed a lawsuit in the amount of up to 100 million if there were environmental consequences that could not have been foreseen during the trial. A huge amount is also the claims of companies and individuals, for many of which the lawsuit continues to this day. Even eight years after the Exxon Valdez accident, in some sediment samples, markers indicated the presence of oil from this tanker [1] .

The ocean remains the site of large and small environmental disasters associated with the transport of extremely dangerous goods. This was the case with the Karen Bi (1987), which carried 2,000 tons of toxic waste on board, and the Akatsuki-maru (1992), which transported a large shipment of radioactive plutonium from Europe to Japan for reprocessing.

In addition to oil, the most harmful waste includes wastewater . In small quantities, they enrich water and promote the growth of plants and fish, and in large quantities they destroy ecosystems. In two of the world's largest discharge sites - in Los Angeles (USA) and Marseille (France) - specialists have been cleaning polluted waters for more than two decades. The satellite images clearly show the spreading of the effluents discharged by the exhaust manifolds. Underwater surveys indicate the death of marine organisms caused by them (underwater deserts dotted with organic debris), but restoration measures taken in recent years have significantly improved the situation.

Efforts to liquefy sewage are aimed at reducing their danger; however, sunlight kills some bacteria. Such measures have been effective in California , where domestic wastewater is discharged into the ocean - the result of the vital activity of almost 20 million residents of this state.

In recent years, the content of metals in the oceans of metals, DDT (insecticide) and PCBs (polychlorodiphenyls) has decreased, but the amount of arsenic has inexplicably increased. DDT (organochlorine-based toxic toxic pesticide) is banned in most developed countries, but is still used in parts of Africa.

Dangerous chemicals that can upset the ecological balance include heavy metals such as cadmium , nickel , arsenic , copper , lead , zinc and chromium . According to estimates, up to 50,000 tons of these metals are discharged annually into the North Sea alone. Pesticides — aldrin, dieldrin, and endrin — that accumulate in animal tissues cause even greater concern. The long-term effects of the use of such chemicals are not yet known.

It is detrimental to marine life and TBT (tributyltin chloride, (n-С ₄ Н ₉ ) ₃ SnCl), which is widely used for painting ship keels and preventing their fouling with shells and algae. It has been proven that TBT changes the sex of male trumpeters (crustacean species); as a result, the entire population consists of females, which excludes the possibility of reproduction. There are substitutes that do not adversely affect wildlife - for example, a copper-based compound is 1000 times less toxic to animals and plants.

All oceans suffer from pollution, but the pollution of coastal waters is higher than in the open ocean, due to a much larger number of pollution sources: from coastal industrial installations to heavy traffic of marine vessels. Around Europe and off the eastern shores of North America, cages are set up on shallow continental shelves to breed oysters , mussels and fish vulnerable to toxic bacteria, algae and pollutants. In addition, oil exploration is underway on the shelves, which increases the risk of oil spills and pollution.

The waters of the Mediterranean Sea are completely renewed every 70 years by the Atlantic Ocean with which it communicates. Up to 90% of wastewater came from 120 coastal cities, while other pollutants account for 360 million people living or on vacation in 20 Mediterranean countries. This sea has turned into a huge polluted ecosystem, which annually receives about 430 billion tons of waste. The most polluted coasts of Spain, France and Italy, due to the influx of tourists and the work of heavy industry enterprises.

Of the local mammals, Mediterranean monk seals were the worst. They have become rare due to the increased flow of tourists , and their remote habitats on the islets are now reachable for speedboats and scuba divers. In addition, more and more seals die, entangled in fishing nets.

Green sea turtles live in all oceans, where the water temperature does not drop below 20 ° C, but their nesting sites are threatened both in the Mediterranean Sea (in Greece) and in the ocean. On the island of Bali ( Indonesia ), turtles eggs are collected and incubated in artificial conditions to release turtles into the sea off the coast, thereby increasing their chances of survival.

Another common form of ocean pollution is water bloom due to the massive development of algae or plankton. The lush flowering of the North Sea waters off the coast of Norway and Denmark was caused by the growth of the algae Chlorochromulina polylepis , as a result of which the salmon fishery was seriously affected. Such phenomena have been known for a long time in the waters of the temperate zone, but in the subtropics and tropics the “red tide” was first noticed near Hong Kong in 1971. Subsequently, such cases were often repeated. It is believed that this is due to the industrial emissions of a large number of microelements, especially the flushing of agricultural fertilizers into water bodies, which act as biostimulants of phytoplankton growth. Consumers of the first order cannot cope with the explosive growth of phytoplankton biomass, as a result of which most of them are not used in food chains and simply die off, sinking to the bottom. By decomposing the organic matter of dead phytoplankton, bottom bacteria often use all the oxygen dissolved in water, which can lead to the formation of a hypoxia zone (with insufficient oxygen content for aerobic organisms). Such zones lead to a reduction in biodiversity and biomass of aerobic forms of benthos ^[1] .

Oysters, like other bivalves, play an important role in filtering water. In the past eight days, oysters completely filtered water in the part of the Chesapeake Bay in Maryland . Today they spend 480 days on it due to flowering and water pollution. After flowering, algae die and decompose, promoting the growth of bacteria that absorb vital oxygen.

All marine animals that obtain food by filtering water are very sensitive to pollutants that accumulate in their tissues. Coral pollution is poorly tolerated, and a serious threat looms over coral reefs and atolls.

Accumulations of plastic waste form special garbage spots in the oceans under the influence of currents. At the moment, five large clusters of garbage spots are known - two in the Pacific and Atlantic oceans , and one in the Indian Ocean . These garbage cycles mainly consist of plastic waste generated as a result of discharges from densely populated coastal zones of the continents. The head of marine research, Kara Lavender Law of the Sea Education Association; SEA, objects to the term “stain,” because by its nature it is scattered small pieces of plastic. Plastic garbage is also dangerous because marine animals, often, can not see transparent particles floating on the surface, and toxic waste gets into their stomach, often causing deaths ^{[2] [3]} .

European environmentalists have calculated: if things continue this way, then by 2025, for every 3 kg of fish in the World Ocean, 1 kg of garbage will be consumed. ^[four]

Pests contained in wastewater breed in mollusks and cause numerous diseases in humans. The most common bacterium, E. coli, is an indicator of infection.

The safe content of Escherichia coli is no more than 230 bacteria per 100 g of tissue. Other microorganisms dangerous to humans are the bacteria Salmonella and Staphylococcus , which infect crustaceans , the bacterium Vibrio parahaemolyticus . PCBs accumulate in marine organisms (have a cumulative effect). These industrial pollutants are poison for animals and humans. Like other ocean pollutants, such as HCH ( hexachlorocyclohexane ) used in pesticides and wood preservatives, they are persistent chlorine compounds.

These chemicals are leached from the soil and into the sea, where they penetrate the tissues of living organisms. PCB or HCH fish can be eaten by both humans and fish. Seals then eat the fish, and they, in turn, become food for some species of whales or polar bears . Each time chemicals move from one level of the food chain to another, their concentration increases. An unsuspecting polar bear, eating a dozen seals, absorbs with them the toxins contained in tens of thousands of infected fish.

It is believed that pollutants are also guilty of increasing the susceptibility of marine mammals to the plague, which hit the North Sea in 1987–88, when at least 11 thousand common and long-faced seals died . It is likely that metallic contaminants in the ocean have also caused skin ulcers and liver enlargement in fish , including flounder , 20% of the population of the North Sea is affected by these diseases.

Toxic substances entering the ocean may not be harmful to all organisms: some lower forms even thrive in such conditions. Polychaete worms (polychaetes) live in relatively polluted waters and often serve as environmental indicators of relative pollution. The study of the possibility of using marine nematodes to control the sanitary state of the oceans is ongoing.

• Large pacific trash spot
• Freshwater pollution

• Zaitsev Yu. P. Introduction to the ecology of the Black Sea. Odessa. Publishing house "Even." 2006.222 s.
• Biotic mechanism of self-purification of fresh and marine waters. M .: MAKS-Press. 2004.
• Markina Zh.V., Aizdycher N.A. Dunaliella salina (Chlorophyta) as a test object for assessing marine pollution with detergents // Marine Biology, 31 (2005), 4 (July), 274–279.
• Introduction to the problems of biochemical ecology. M .: Science. 1990.288 s. ISBN 5-02-004062-2 .
• Fellenberg G. Environmental pollution. M .: World. 1997.232 s.

International agreements

• International Convention for the Prevention of Pollution from Ships (MARPOL 73/78)
• Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Materials
• Convention on Offshore Intervention in the Case of Accidents leading to Oil Pollution
• International Convention on Oil Pollution Preparedness, Control and Cooperation
• International Convention on Civil Liability for Oil Pollution Damage
• International Convention on the Establishment of an International Fund for Compensation for Oil Pollution Damage
• Helsinki Convention (Convention on the Protection of the Natural Marine Environment of the Baltic Sea Region)
• Framework Convention for the Protection of the Marine Environment of the Caspian Sea
• Convention on the Protection and Use of Transboundary Watercourses and International Lakes
• Protocol on Water and Health to the 1992 Convention on the Protection and Use of Transboundary Watercourses and International Lakes
• Protocol on civil liability and compensation for damage caused by the transboundary effects of industrial accidents on transboundary waters
• Agreement between the Government of Ukraine and the Government of Russia on the joint use and protection of transboundary water bodies

Ocean Ecology

• Hans-Otto Pertner, 2009. Is ocean acidity increasing?