The Sea of Azov is a unique environmental object. Everyone understands the importance of keeping it clean as a source of not only material, but also spiritual wealth. This once wonderful natural site needs serious protection.
The Sea of Azov, whose problems are poor environmental conditions as a result of the economic activity of the coastal countries, is going through hard times. In the last decade, the volume of environmental protection has significantly decreased , which, without exaggeration, threatens disaster.
During the period of the existence of the USSR, the state implemented a relatively successful hydrosphere protection policy. In the 90s, both Russia and Ukraine underwent large-scale economic and political changes, against which environmental issues were abandoned. However, due to the economic downturn, the ecosystem load has also decreased.
As countries in the region were affected by economic growth, the environmental impact increased. By 2008, the industrial output of Russia and Ukraine exceeded the level that existed in the USSR. Disposal of waste and other pollutants into the sea with sewage also increased proportionally.
What is the Sea of Azov
It belongs to the lateral basin of the Black Sea from the north-east, connecting with the last Kerch Strait. This sea is the smallest in the world. The average depth of the Sea of Azov, even in the most “serious” places, does not exceed 13.5 m, and the width of the strait is 4.2 km. Its extreme points are located at latitudes 45 ° 12′30 ″ and 47 ° 17′30 ″, longitudes 33 ° 38 ′ and 39 ° 18 ′. On the whole, the average depth of the Sea of Azov ranges from 6.8 to 8 meters. Its greatest length is 343 km, the maximum distance is 231 km wide. The sea surface area is 37605 km, and the coastline stretches for 1472 km.
The Sea of Azov, the temperature of which is subject to large seasonal changes, is a relatively small body of water. In relief, it is a flat sea with low shores. The geographical position undoubtedly gives it its own characteristics. Perhaps not everyone knows that the most continental on the planet is the Sea of Azov. Its temperature in the summer is + 24 ... +26 ° C. In winter, it freezes in whole or in part; in spring, ice is carried through the strait to the Black Sea.
The salinity of the Sea of Azov is quite low. On average, it is three times less than the usual salinity of the ocean. This value is about 1 ppm in the area of the confluence of the Don and increases to 10.5 ppm closer to the central part. In the Kerch Strait region, the salinity of the Sea of Azov reaches a maximum of 11.5 ppm.
What do we know about its inhabitants? The Sea of Azov, whose biological resources were initially quite large, now has 103 species of fish. Plankton biomass reaches a size of 200 g per square. m
Ecological problems of the Sea of Azov
The main negative technological factors are untreated sewage from rivers containing household waste. Formerly a world leader in fisheries, this sea has now lost all its significance. Now the content of phenols exceeds the MPC by 7 times, of thiocyanate - by 12.6.
The main sources of sea pollution are ports and industrial enterprises of Mariupol. The Azovstal Steel Works annually releases more than 800 million cubic meters of polluted effluents into its waters.
They revealed an excess of the MPC for nitrogen, iron, copper, zinc, and petroleum products. Another major pollutant is the commercial port of Mariupol. Its treatment facilities are completely ineffective - pollution indicators are higher in the water area than anywhere else.
What ecologists worry about
Experts are worried about the increase in sulfur volumes, which are being reloaded in Ukrainian ports, as well as the deterioration of water intake systems built half a century ago, the lack of sewage treatment systems in many villages and cities, as a result of which dirty water directly flows into the sea. According to statistics, the volume of effluents discharged into the Sea of Azov annually reaches 5 billion cubic meters.
The pollution of the sea by oil products due to cargo transportation and port activities has become catastrophic.
Their concentration in the Sea of Azov in places exceeds all conceivable limits. The content of pesticides reaches 40 mg / l. Due to spilled oil, oxygen exchange is impaired, aquatic organisms are poisoned by pesticides. There is a massive death of fish. The water protection zone contains a lot of industrial and household waste.
Dangerous fishing
Other environmental problems of the Sea of Azov are associated with its inhabitants. Bottom trawling has long been officially prohibited, but, nevertheless, it is used almost everywhere. As a result, near-bottom fish habitats are destroyed, filter mollusks, the fish feed base, are killed. The rising turbidity over several kilometers reduces the transparency of the water.
Only a part of fishing vessels has permission to work with a net with limited catch. But in fact its volumes are hidden. In addition, trawls are often used instead of seines, as a result of which not only fish stocks are destroyed, but also places of spawning and feeding. Poaching in recent years has led to a decrease in production by 5 times.
Other points
What else bothers ecologists? There are a lot of questions, and their list is far from exhausted. This is the construction of reservoirs on the Don and Kuban (the main rivers of the Sea of Azov), gradually turning into giant sedimentation tanks. And the chemical contamination of the surrounding soils as a result of the introduction of irrigated agriculture with rice sowing. And uncontrolled discharge of pesticides.
In addition, the problems of the intensive construction on the coast of many recreation centers and boarding houses, which is conducted without observing any sanitary and environmental standards, adversely affect the Sea of Azov. At the same time, the natural state of the beaches is violated and their potential decreases.
Another serious problem is dumping, i.e. dumping of ship and aircraft waste at sea or their planned destruction. At the same time, seawater is contaminated with mercury and lead, which tend to accumulate in its upper layers.
Sea of Azov - problems and solutions
The only possible way to solve urgent issues, environmental scientists consider a fundamental change in priorities for the region. It should be to minimize production and the transition to fisheries and recreation. The port and transport infrastructure requires tight control over the activities of ports and shipping, reduction in the volume of transport of harmful and dangerous goods, modernization of treatment facilities and the construction of new ones.
Reducing the volume of water consumption of industries, increasing fines for unauthorized discharge of effluents can help.
In coastal regions, a revision of the principles of agriculture, the abandonment of crops that are grown using pesticides and hazardous fertilizers, and the restoration of places for spawning of fish and its migration routes are required.
Measures are needed to tighten laws regarding the protection of the coastal zone and regular monitoring of the ecological state of the coastal and marine environment, a categorical ban on the discharge of untreated sewage and drainage water into the sea.
What cleaning methods exist today?
Physical and chemical methods
Mechanical cleaning is used when insoluble solids are to be removed. This is done by filtering, filtering, settling and removing suspended particles by spin and centrifugal force.
Chemical methods are used to eliminate soluble substances from water. For this, reagents that reduce the toxicity or solubility of harmful impurities are used. Chemical methods: oxidation and reduction, neutralization, removal of metal ions.
Physicochemical methods, i.e., combined methods, make it possible to get rid of impurities in the form of emulsions and suspensions of substances (both organic and inorganic) dissolved in water. The names of the main methods: coagulation, ion exchange, deodorization, adsorption, degassing, flotation, ultrafiltration and others.
The thermal method is used when it is required to remove organic substances and mineral salts from wastewater. This happens by concentrating the effluents and separating sediment from them, oxidizing organic substances with the help of catalysts under pressure, and also neutralizing them with fire.
Biochemical agents and methods
Such methods exist to purify water from most of the organic and partially inorganic elements dissolved in them. Such a process is based on the ability of some plants and microorganisms to consume harmful substances as food.
Such a cleaning process has two stages, the flow rate of which is different:
1. Adsorption of dissolved and finely divided impurities by microorganisms.
2. Destruction of a harmful substance intracellularly by a chemical process.
For almost non-oxidizable inorganic substances set the maximum concentration.
Where and how does biochemical treatment take place?
Such a method is possible in both artificial and natural conditions. The latter include irrigation fields, biological ponds, filtration, etc.
Irrigation fields are special sites combining the cultivation of useful crops with wastewater treatment. If nothing is grown, these are filtering fields. Soil methods are now very popular as a way to intensify crop production.
Biological ponds complement the complex of treatment facilities. These are shallow ponds, divided into sections. They work only in the summer.
Conclusion - in order to avoid environmental disaster, a clear state policy is required to protect the marine ecosystem. If you do not start saving the Sea of Azov now, problems can take on an irreversible character.