On the territory of Russia, more than a hundred large objects have been built - artificially created water accumulations with the help of dams. In this article, we will consider in detail what a reservoir is, its main characteristics, and 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 Eurasian continent. Its territories stretch 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 amounts of fresh water. Artificial reservoirs have long been used for domestic needs of the population and irrigation of crops. The oldest man-made reservoir is the Egyptian Sadd al-Kafar, built before our era. Since the beginning of the 20th century, the construction of suchreservoirs became ubiquitous. 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, Kuibyshev in Russia on the Volga and Bratsk on the Angara.
Destination
The total area of all water bodies of the world created by man in history is more than 400 thousand square kilometers. Most reservoirs are located in Europe, Asia and North America. What is a reservoir for people, except for 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 soil irrigation, water supply for the population and industry, hydropower and transport routes. Also used for flood prevention.
Reservoirs are often favorite places for recreation and fishing. However, despite the positive economic effect, the construction of dams often causes negative consequences affecting the ecology of adjacent territories.
Categories of artificial reservoirs
Reservoirs can be classified according to several criteria:
- structure;
- location in the river basin;
- filling method;
- degree of water level regulation;
- geographic location.
By the nature of the bed of the reservoir are divided into:
- Valley - part of the riverthe valley, partitioned off by the dam, is a bed. The direction of the bottom slope from the top to the dam is the main feature that defines this reservoir. The depth increases towards the dam. Can be channel and floodplain-valley.
- Hollow - located in lowlands isolated from the sea with the help of dams.
According to the place in the river basin:
- Horsebacks.
- Grassroots.
- Cascade - a stepped system on a river bed.
By filling with water:
- Liquid.
- dammed.
By the nature of water level regulation:
- Multi-annual - Stock filling can take place over several years.
- Daily - the level is constantly adjusted.
- Seasonal - water is released at certain times of the year. Seasonal runoff is used to artificially irrigate agricultural land in the spring and summer and reduce the potential risk of flooding.
Winter level drops are dangerous for the flora and fauna created with the help of the reservoir dam. If seasonal runoff occurs on the reservoir in winter, layers of ice settling on the drained bottom press down a large number of fish.
By geographic location:
- Flat - a wide reservoir, the height of the water level is not more than 30 meters.
- Mountain - the magnitude of the level increase can reach more than 300 meters.
- Piedgornoe - water levels are within 100 meters.
- Primorskoye - a pressure of several meters, being built in sea bays.
What is a reservoir for a fisherman and a tourist?
Changing the riverbed has a negative impact on fish spawning. As a result of changes in the food base and places of accumulation of populations, the species composition is gradually becoming poorer. Valuable breeds are disappearing. However, fishing in the reservoir is often successful.
Large reservoirs are characterized by their own microclimate. Often large freshwater reservoirs are called the sea. On an open water surface, waves arise, which, due to the absence of natural obstacles in the form of islands, are distinguished by a large height. Not only the inhabitants of the surrounding shores prefer to rest on the reservoir, picturesque landscapes and rich fauna attract numerous tourists and travelers.
Environmental impact
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 the flooding of lands, the rise in the level of groundwater, and the swamping of coastal zones. The total area of the territories that have gone under water is approximately 240 thousand square kilometers. Silting of reservoirs is a process of formation of large deposits on the bottom, leading to a decrease in the water level. It is also assumed that the additional load in the form of a mass of accumulated volumes of water can lead to an increase in the level of seismicity.
The construction of reservoirs entails many different consequences. In the process of creation anddam operation should be carefully planned construction and take into account environmental forecasts.
