What are the main organic pollutants in seawater?

Marine organic matter pollution refers to the pollution (excluding petroleum and organic pesticides) caused by excessive organic matter (carbohydrates, proteins, oils, amino acids, fatty acid esters, etc.) and nutrients (nitrogen, phosphorus, etc.) in domestic sewage, industrial wastewater, agricultural and animal husbandry drainage and surface runoff sewage entering the estuary.

The harmful effects of organic pollution mainly depend on the type and quantity of sewage entering the sea, as well as the purification capacity of the receiving water. Its direct or indirect harmful effects mainly include:

Covering, shading. The organic matter that enters the ocean partially floats or is suspended on the surface of the sea, increasing the turbidity of the seawater, affecting the photosynthesis of marine plants and the migration of fish, and destroying spawning grounds. Viscous substances such as cellulose, which have a strong covering force, can suffocate marine animals.

Oxygen consumption. Excess organic matter consumes a large amount of dissolved oxygen during microbial degradation. It has been determined that the lignin discharged from each ton of pulp produces 200 500 kg of oxygen, which can deplete the oxygen in 270,000 tons of ordinary seawater, and most of the lignin entering the sea sinks to the seabed, causing hypoxia in the seawater near the bottom, causing the formation of sulfides and directly harming organisms.

A large amount of organic matter is discharged into the sea, which promotes eutrophication of water bodies, leads to the simplification of biota composition, and the growth of sewage organisms, which disturbs or destroys the marine ecological balance.

Pathogenic, toxic. Excess nutrients are discharged into the ocean, becoming nutrients for various bacteria and viruses and causing them to multiply, which in turn affects human activities; Viruses in seawater can also enter the body of fish and shellfish, directly endangering the growth and development of fish and shellfish, or enter the human body through food, causing various diseases (see Marine Pathogen Contamination). Istanbul, Turkey, for example, has exposed residents to typhoid, hepatitis, E. coli, dysentery and gastroenteritis due to the proliferation of germs in sewage.

According to a survey by the city's public health organization in the early 70s of the 20th century, 7 of the 22 bathing beaches were heavily polluted by sewage and were forced to close. Excessive nutrients can cause cancer. Furfural, which is toxic, can also cause bleeding in the gills and liver of fish, leading to its death.

Papermaking wastewater containing staple fibers can kill shrimp seedlings.

The main marine pollutants are petroleum and its products.

According to the nature and toxicity of pollutants, as well as the way of harm to the marine environment, the main pollutants are as follows: Petroleum and its products: including solvent oil, gasoline, kerosene, diesel, lubricating oil, paraffin, asphalt, etc., as well as various products that have been cracked and catalyzed.

The oil pollutants discharged into the sea every year are mainly caused by industrial production, including offshore oil well pipeline leakage, oil tanker accidents, ship discharge, etc., especially some sudden accidents, the amount of oil leaked at a time can reach more than 100,000 tons, which makes a large area of seawater covered by oil film, promotes the death of a large number of marine organisms, seriously affects the value of seafood, and other marine activities.

Introduction to Marine Pollution:

Marine pollution usually refers to the destruction of marine ecosystems by humans who have altered the original state of the ocean. Harmful substances entering the marine environment and causing pollution in the ears will damage biological resources, endanger human health, hinder fishing and other human activities at sea, and damage the quality of seawater and the environment.

The oceans have long been the most stable ecosystems on the planet due to their vast size and huge water reserves. The various substances that flow into the ocean from the land are accepted by the ocean, but the ocean itself has not changed significantly. However, in recent decades, with the development of the world's industry, the pollution of the ocean has become increasingly serious, which has greatly changed the local sea environment and has a tendency to continue to expand.

Petroleum and its products: It is mainly lost in the process of exploitation, transportation, hail refining and use, etc., and is directly discharged or indirectly transported into the sea.

Metals and acids and alkalis: mainly from industrial and agricultural wastewater and the exhaust gas generated by the combustion of coal and oil are transferred to the sea.

Pesticides: Mainly from forests, farmland, etc., pesticides are applied and migrate into the sea with water currents, or escape into the atmosphere, and settle into the sea through transportation.

The source of radioactive materials is Zheng: mainly from the nuclear ****, the nuclear industry and the discharge of nuclear-powered ships.

Organic waste and domestic sewage: mainly cellulose, lignin, pectin, sugars, chaff aldehydes, greases, etc. from papermaking, printing and dyeing and food industries, as well as feces, detergents and various food residues from domestic sewage.

1. Main components: that is, substances with a concentration greater than 1 106mg kg in the water of sea anthems, the main hunger and reform friends should have 5 kinds of cations such as Na+, K+, Ca2+, Mg2+ and SR2+, and 5 kinds of anions such as Cl, SO42, BR, HCO3 (CO32)F, and Rotten locust . Second, the main impurities:

1. Gaseous substances dissolved in seawater, main.

Oil pollution is the pollution caused by oil leakage and discharge during the extraction, transportation, loading and unloading, processing and utilization of oil. The total annual production of oil in today's society is about 22x10 8t and the amount of oil field production is about. Every year, 8x10 6t of oil pollution alone enters the environment, and the current oil pollution problem is very serious.

Pollution caused by petroleum and its products entering the marine environment during exploitation, refining, storage, transportation and use. The discharge of various oily wastewater, ballast water and tank washing water from offshore ships, oil tanker shipwrecks, leaks from oil pipelines and offshore oil extraction are all important ways of marine oil pollution. It is estimated that more than 600 million tons of oil enter the sea every year through various means.

After the oil enters the sea, a series of changes occur immediately, including diffusion, evaporation, dissolution, emulsification, photochemical oxidation, microbial degradation, sedimentation, formation of asphalt balls, etc. Oil pollution can damage seaside landscapes and bathing beaches.

Oil films on the surface of the sea can hinder the exchange of gases between the atmosphere and seawater, affecting the photosynthesis of marine plants. When the fur and feathers of sea animals and seabirds are contaminated with oil, they lose their ability to keep warm, swim or fly.

Petroleum pollutants can also interfere with the feeding, reproduction, growth and development of marine organisms, change the migration routes of fish, contaminate fishing gear and catches, and make seafood unedible due to its petroleum taste.

The main types of marine pollution are: oil and its products, metals, pesticides, radioactive substances, organic waste and domestic sewage, thermal pollution and solid waste. Marine pollution usually refers to the destruction of marine ecosystems by humans who have changed the original state of the ocean.

Pollution caused by harmful substances entering the marine environment can damage biological resources, endanger human health, hinder fishing and other human activities at sea, and damage the quality of seawater and the environment.

Marine pollution is characterized by many sources, strong persistence, wide spread, and difficult to control. The turbidity of the sea caused by marine pollution seriously affects the photosynthesis of marine plants (phytoplankton and seaweed), thus affecting the productivity of the sea and is also harmful to fish.