On the territory of Russia, more than a hundred large objects have been built - water accumulations artificially created using dams. In this article, we consider in detail what a reservoir is, its main characteristics, the role of environmental impact.
Reservoir - what is it?
What is a reservoir? This is a water body, a component of the landscape, artificially created by man. The hydrological river regime is regulated in accordance with the necessary requirements. The use of accumulated water in the reservoir is determined by economic needs.
The role of artificial reservoirs
Russia occupies vast areas of the Eurasia continent. Its territories extend from the shores of the Arctic Ocean to the southern steppes and deserts. Not everywhere there is an abundance of rivers and lakes that fully satisfy human needs. The national economy requires large expenditures of fresh water. Artificial ponds have long been used for the domestic needs of the population and irrigation of crops. The most ancient man-made reservoir is considered the Egyptian Sadd el-Kafar, built before our era. Since the beginning of the 20th century, the construction of such reservoirs has become widespread. Now there are more than 60 thousand artificially created reservoirs on the planet . The largest reservoirs in the world are Nasser in Egypt on the Nile River, Volta in Ghana, in Russia Kuybyshevskoye on the Volga and Bratskoye on the Angara.
Appointment
The total area of all reservoirs of the world created by man in the whole history is more than 400 thousand square kilometers. Most reservoirs are located in Europe, Asia and North America. What is a reservoir for people, besides large reserves of water used for basic household and household needs? The operation of artificial reservoirs allows a more reasonable use of water resources - the accumulated water masses are used for irrigation of the soil, water supply to the population and industry, hydropower and transport routes. Also used to prevent flooding.
Often reservoirs are favorite places for recreation and fishing. However, despite the positive economic effect, the construction of dams often causes negative consequences affecting the ecology of neighboring territories.
Artificial Tank Categories
Reservoirs can be subdivided according to several criteria:
- structure;
- location in the river basin;
- filling method;
- degree of regulation of water level;
- geographical location.
By the nature of the reservoir bed are divided into:
- Valley - a part of a river valley blocked by a dam is a bed. The direction of the slope of the bottom from the upper part to the dam is the main feature that defines this reservoir. Depth increases to the dam. Can be channel and floodplain-valley.
- Basin - located in lowlands isolated from the sea with the help of dams.
By place in the river basin:
- Horseback.
- Grassroots.
- Cascade is a stepped system on a river bed.
By water filling:
- Bulk.
- Dams.
By the nature of the regulation of the water level:
- Perennial - filling the bed can occur over several years.
- Daily - the level is constantly regulated.
- Seasonal - water discharge occurs at a certain time of the year. Seasonal runoff is used for the artificial irrigation of agricultural land in the spring-summer period and to reduce the possible risk of flooding.
Winter lowering levels are dangerous for the plant and animal world created with the help of a reservoir dam. In the event that seasonal runoff occurs at the reservoir in winter, ice strata deposited on the drained bottom crush a large number of fish.
By geographic location:
- Plain - a wide reservoir, the height of the water level is not more than 30 meters.
- Mountainous - the level increase can reach more than 300 meters.
- Piedmont - water level indicators are within 100 meters.
- Primorsky - a pressure of several meters, is being built in sea bays.
What is a reservoir for a fisherman and a tourist?
A change in the riverbed has a negative effect on fish spawning. As a result of changes in the food supply and population centers, the species composition is gradually becoming poorer. Valuable breeds disappear. However, fishing in the reservoir is often successful.
Large reservoirs are characterized by their own microclimate. Large freshwater reservoirs are often called the sea. Waves appear on an open water mirror, which due to the lack of natural obstacles in the form of islands are distinguished by a high height. Not only residents of the surrounding coasts prefer to rest on the reservoir, picturesque landscapes and rich fauna attract many tourists and travelers.
Impact on the environment
The construction of reservoirs can adversely affect the natural conditions of the surrounding area. The most serious negative consequences of the construction of large reservoirs are land flooding, rising groundwater levels, and swamping of coastal zones. The total area of territories that went under water is approximately 240 thousand square kilometers. Siltation of reservoirs is a process of formation of large sediments at the bottom, leading to a decrease in water level. It is also assumed that the additional load in the form of the mass of accumulated volumes of water can lead to an increase in seismicity.
The construction of reservoirs entails many diverse consequences. In the process of creating and operating dams, construction should be carefully planned and environmental forecasts should be considered.