1. Types of surface water pollution. Pollution of sea waters

Marine pollution

This section is an excerpt from Marine pollution.[edit]
Marine pollution occurs when substances used or spread by humans, such as industrial, agricultural and residential waste, particles, noise, excess carbon dioxide or invasive organisms enter the ocean and cause harmful effects there. The majority of this waste (80%) comes from land-based activity, although marine transportation significantly contributes as well.[38] Since most inputs come from land, either via the rivers, sewage or the atmosphere, it means that continental shelves are more vulnerable to pollution. Air pollution is also a contributing factor by carrying off iron, carbonic acid, nitrogen, silicon, sulfur, pesticides or dust particles into the ocean.[39] The pollution often comes from nonpoint sources such as agricultural runoff, wind-blown debris, and dust. These nonpoint sources are largely due to runoff that enters the ocean through rivers, but wind-blown debris and dust can also play a role, as these pollutants can settle into waterways and oceans. Pathways of pollution include direct discharge, land runoff, ship pollution, bilge pollution, atmospheric pollution and, potentially, deep sea mining.
Up to 12 million tons of oil flows into rivers and oceans every year.
It is impossible to imagine the amount of pollution that is accumulating! Oil quickly covers the surface of the water with a thin film of oil. This layer prevents the passage of air and light. 10 minutes after 1 ton of oil falls into the water, an oil "spot" is formed. Its thickness is 10 millimeters. Over time, the thickness of the plyon decreases (to less than 1 millimeter), and the spot expands. One ton of oil can cover an area of up to 12 square kilometers.
Further changes are caused by wind, tide and weather. Usually the spot changes direction with the force of the wind and gradually breaks up into smaller spots. Hurricanes and hurricanes speed up the flight process.
Fish, reptiles, animals, and plants don't die off in large numbers all at once when oil spills occur. However, the impact of the oil spill in the medium and long term is very severe. It has a particularly severe effect on organisms living in coastal areas, at the bottom and on the surface. -
Oil is collected using suction cups equipped with a special nozzle. They allow oil to be collected from the water surface. And flexible float sleeves repel oil.
The problem with collecting oil using suction cups is that the oil forms a very thin layer of oil. It cannot be harvested without a large amount of water. An additional complication of oil collection is the vibrations (vibration) created by the suction and sleeves.
Burning oil at the spill site causes secondary pollution and adversely affects the ecology of the affected area.
Therefore, this method should be used only in justified cases.
The problem with oil burning is that once the light fractions burn off, the spot burns, leaving the heavy components of the oil untouched.
Birds ingest the oil when they clean their feathers with their beaks, drink it, and eat contaminated food. These creatures that live in the vastness of the ocean breathe in spilled oil products. Oil ingestion is rarely the direct cause of bird death.
Oil spills kill marine mammals. Sea beavers, polar bears, seals, newborns
sea cats (distinguished by their fur) are killed in most cases. Oil-contaminated fur becomes tangled and loses its ability to retain heat and water. Oil affects the fat layer of seals and cetaceans and heat
increases consumption. In addition, the oil causes reddening of the skin and eyes and hinders the ability to swim.
Bacterial contamination may also occur. Bacteria and viruses that cause various diseases can enter the water. In order not to suffer from dangerous infectious diseases, we must follow several important rules of sanitation and hygiene:

- use only specially equipped toilets located far from rivers and water bodies;

- always wash hands with soap after using the toilet and before eating;

- consume only recently boiled water;

- rinse uncooked fruits and vegetables with boiled water.

The relationship is also mechanical. If sand, silt, mud (a powdery product formed during rock crushing, drilling) and other substances fall into the water, the particles in it - particles (liquid or gas in which solid particles are suspended) increase. This leads to deterioration of water quality.

A type of heat exhaustion is also observed. This happens when the temperature of the wastewater is higher than the temperature of the water in the river and reservoir. If the wastewater is too warm, it can seriously affect fish and aquatic plants, and even kill them. As the temperature of the lake rises from the hot springs, it can become covered with algae or become a swamp over time.Radioactive contamination of water is especially dangerous. It is very dangerous for human and animal life even in very small concentrations of radioactive substances. They fall into rivers and water bodies when radioactive waste is discharged and buried at the bottom. It goes to underground water - when it is absorbed by atmospheric water. Radioactive elements (uranium, cesium, etc.) that "live long" and move in water are the most harmful.
In conclusion, it can be said that there are many negative consequences of pollution. It has a bad effect on living organisms and can cause their death. Fish in reservoirs can survive without high levels of chemical pollution in the water, but eating them can be very harmful to human health.
Although our planet is called Earth, we must not forget that the oceans make up more than 70% of the earth's surface and make up 97% of all the water on the planet. We also cannot forget that the oceans contain a large amount of flora and fauna belonging to the world. Thousands and thousands of species of bacteria, microorganisms, animals and plants live in these saltwater pools. It should also be taken into account for humans, because it is a very important source of natural resources. We extract energy, food and minerals from the oceans. However, due to human activity, what is known is Marine pollution.
It is well known that the ocean is home to thousands of living creatures and a great source of natural resources for humans. From here we get energy, food and minerals, including things that last us a day. Unfortunately, there are many spills that cause marine pollution due to human activities. As we use vast bodies of water, we degrade them.We can say that marine pollution is a consequence of the introduction of external environmental, chemical or biological agents into these ecosystems. When we discharge water from agriculture into watercourses such as rivers, it flows into the sea. This water is contaminated with pesticides, fertilizers and herbicides used to grow plants. Therefore, it is a type of marine pollution. As a result of this pollution, we have degraded the natural features of the ecosystem. When these characteristics are altered, they ultimately affect the quality of life of all living things. It also leads to the destruction of natural habitats and fragmentation between them.Over the years, human development has led to the generation of waste water without any treatment method. various chemicals and even radioactive waters dumped into the sea. Until the 70s of the last century, it was widely believed that due to the amount of water in the oceans, all pollutants could be diluted without causing environmental consequences. Later it turned out that this was not the case.
Contrary to popular belief, pollution does not dilute, but rather accumulates in water, in food chains. It then spreads across ocean waters around the world, reaching places where human activity does not exist. In fact, we know the consequences of pollution in places that have not been occupied by humans, or it is through the Mariana Trench in Antarctica.
The causes of marine pollution come from many sources. Most of them are related to the economic activity of people. Let's see what are the main sources of marine pollution.Pesticides and herbicides
As we mentioned earlier, various chemicals are used in agriculture to help reduce pests and diseases that attack crops. Herbicides are used to kill weeds that inhibit the growth of crops. These chemicals dilute seawater and reduce populations of phytoplankton, algae, and other marine plants. As a result, dissolved oxygen in water decreases and can accumulate in body tissues. The problem of these chemical contaminants, which are resolved in the tissues, is transferred to the food chain. Finally, breeding these fishes can lead to behavioral changes, as they pose a problem to humans by eating them.Fertilizers and detergents This is one of the main causes of marine pollution. Both chemicals cause nutrient enrichment in the water. This excess of nutrients is known as eutrophication. They consist mainly of nitrogen and phosphorus. Once these reach the water, algae begin to grow rapidly. Here, they form a layer of biomass that blocks sunlight and oxygen regeneration in the water. Therefore, it prevents the development of life in areas with eutrophic waters. Surface water Surface water includes natural waters such as rivers, lakes, ponds, and oceans on the surface of the earth. These substances come into contact with water and dissolve or physically mix in it.Oxygen absorbers There are microorganisms in the water body. These include aerobic and anaerobic organisms. Water usually contains aerobic or anaerobic microorganisms, depending on the biodegradable substances suspended in the water. Excess microorganisms consume and reduce oxygen, which causes the death of aerobic organisms and produces harmful toxins such as ammonia and sulfur. Underground pollution
Pesticides and soil-bound chemicals are washed by rainwater and absorbed into the soil, thereby contaminating groundwater. Microbial contamination In developing countries, people drink untreated water directly from rivers, streams, or other sources. Sometimes there is natural contamination caused by microorganisms such as viruses, bacteria and protozoa.
Perhaps it is natural pollution that causes serious human illness and the death of fish and other species. Contamination by suspended matter
Not all chemicals dissolve easily in water. These are called "particles". These types of substances can harm or even kill aquatic organisms.Chemical pollution of water It is popular to see how various industries use chemicals that are dumped directly into water sources. Agrochemicals that are overused in agriculture to control pests and diseases eventually end up in rivers, poisoning aquatic organisms, destroying biodiversity, and endangering human life.Food contamination
We say many times that water contains useful food for living things, so it does not need to be disinfected. But the discovery of high concentrations of agricultural and industrial fertilizers in drinking water changed the whole situation.Most sewage, fertilizers and sewage contain large amounts of nutrients that encourage the growth of algae and weeds in the water. it is undrinkable and even clogs filters.
Fertilizer runoff from agricultural land pollutes water in rivers, streams, and lakes before it reaches the ocean. Fertilizers are rich in various nutrients needed for plant life, and the resulting clean water changes the natural balance of nutrients needed by aquatic plants.
It is known that for thousands of years, our ancestors regarded water as sacred and considered the saying that if you pollute it you will go blind as a law, they revered water, used it wisely, and freely used the water in the ditch as drinking water. Later, as a result of the development of industry and agriculture, the waters became unusable as a result of the use of various chemical agents. As a result, state control of water and water use has become not only necessary, but also necessary. This means that it is necessary to pay special attention to the identification of sources of drinking water pollution and the development of effective methods of their neutralization, and it is one of the urgent problems of today [1, 3].

95% of the water consumed in Uzbekistan is taken from rivers and streams. In order to deliver water to consumers in a timely manner and in the required amount, many canals and ditches, permanent pumping stations were built. The agriculture of our republic is based on irrigation farming. In the water industry, there are 75 large canals with a total water consumption of more than 2,500 cubic meters per second, 53 water and 32, 4 thousand kilometer inter-water canals with a total volume of 18.6 cubic meters, 4,889 pumping units, 1,479 permanent there are pumping stations, 10,180 vertical drains and water exit wells, 30,400 kilometers of inter-farm collectors [6].

The year-by-year increase in the world's population is creating new, never-before-seen problems. Another such urgent problem is drinking water. On the surface, water on our planet seems to be limitless. But in fact it is not so. If all water reserves in the world are 1,500 million cubic km, 94% of it is ocean and sea water. Only 6 percent of water reserves are underground water and glaciers. The world's potable water is only 0.0221% of all water reserves, as it can be seen, the issue of drinking water is on the agenda as one of the most pressing problems in the world [2, 5].
The acute shortage and pollution of water resources, including surface and underground water, is a big concern for Uzbekistan. Rivers, canals, reservoirs and even underground water in our region are affected by human activities. The depletion of water reserves and the worsening of the quality of water in the basins in our region since the 1960s were negatively affected by the large-scale development of new lands, the development of industrial and livestock complexes, the construction of collector ditch systems, and the increase in urbanization.
All kinds of harmful substances accumulate in water, changing the physical properties and chemical composition of water. The amount of organic and mineral additives increases. Toxic compounds appear. Oxygen in the water is reduced. The types and amount of bacteria change, and bacteria that spread infectious diseases appear.
Water is again polluted with waste water, oil, radioactive substances, etc. from industrial and municipal farms.
The clean water used in the industry of developed countries is several times more than the water used in communal households. Waste water is considered unsuitable for human drinking water supply. Because water saturated with toxic substances has a negative effect on human health. It causes various infectious diseases. Later, doctors discovered that the germs of poliomyelitis, yellow fever and tuberculosis spread through water.
In the chemical industry, synthetically produced paint, explosives and various medicines, rubber, artificial fiber, etc., require a large amount of clean water. As a result, harmful substances that are not found in nature can be found in the dirty water from such production sources [4].

Water is also used in mining coal. Depending on the composition of the rocks between the coal seams, the water is saturated with different substances. Sometimes mines are filled with groundwater. As a result, it greatly damages the work process. In such cases, the dirty water from the mines is discharged into different water bodies with the help of powerful pumps.

Surface waters are being polluted due to ferrous and non-ferrous metallurgy, chemistry, paper, oil refining, mining waste, and agriculture.
Extraction of oil from the oil industry is one of the main causes of transportation and processing and pollution of water bodies. Regrettable incidents occur when extracting oil from underwater. For example, the first oil well in Santo Barbara lost 900 tons of oil in 10 days. Several oil tankers crashed and spilled thousands of tons of oil into the ocean. As a result, several thousand tons of water surface is covered with a thin film of oil.

One liter of oil pollutes 200 liters of water. Or a drop of oil 1- 1.5 square meter cubic water surface thin film