What is the difference between lowland and mountain rivers? Their examples and features
Rivers - large natural watercourses. Eating from precipitation, glaciers or underground sources, they are the main reservoirs on the planet. By the nature of the area in which they flow, emitmountain and flat rivers. Examplesand those and other watercourses are found on all continents. Their appearance and many characteristics are not the same. Read more aboutWhat is the difference between lowland and mountain rivers?, we'll talk further in the article.
What influences rivers?
The nature and appearance of the watercourses of the planet depend on a huge number of factors. They are mainly determined by the climate, geological structure and landscape of the area. Thus, during heavy precipitation, rivers can overflow from their banks, flooding nearby territories. But the prolonged lack of precipitation in hot countries leads to the fact that the streams dry up completely, appearing only in the short rainy season.
If you talk aboutWhat is the difference between mountain rivers and plains?first you need to mention relief. It is he who determines the speed with which water flows, what size, shape, depth will be at the channel and valley. In addition to the relief, the geological structure of the territory also affects the formation of rivers. Together they affect the transparency of the water, and the obstacles it encounters in its path. Now let's find out moreWhat is the difference between lowland and mountain rivers?and how they are affected by all the factors mentioned above.
Waters and flow rates
Mountain rivers are fast, rapid streams, with a flow velocity of 1 meter per second and higher (sometimes higher than 5 m / s). They occur mainly in the mountains or on elevations. They are often formed in places where rocks protrude to the surface, so their waters are usually not very turbid. The most famous examples of such watercourses are Congo, Colorado, and Yangtze.
The relief of our planet is very heterogeneous. Where the high ridges gradually turn into lowlands and plateaus, mountain rivers become flatlands. An example would be the Terek flowing in the North Caucasus.
The flat rivers flow quieter and slower.Their speed usually does not exceed one meter per second. An example of such watercourses is the Amazon, Nile, Mississippi, Volga, Dnieper.Why is a mountain river faster than a flat? Everything is obvious here - because of the greater height difference. Mountain rivers begin at elevations, which means that their angle of incidence is much greater.
One of the main parameters that characterizes a river is its slope. It is the ratio of the height of the fall of the watercourse (or its section) to its length. For mountain rivers, it can be 5–80 m / km, while for flat rivers it is only a few centimeters per kilometer of length.
River Valley Shape
All rivers arise from tiny streams that appear from excess water (heavy rainfall, melting snow, overcrowded swamps or lakes, etc.). They themselves form their own way, punching furrows in the soil and rocks. The deepening of the earth’s surface, formed by a watercourse, is called the valley, and the deepest part, where it flows directly, is called the channel.
What is the difference between mountain rivers and plains?? Its shape. Lowland streams are too slow. Their current is unable to overcome the barrier, so it goes around it.The valleys of such rivers are wide, and the channels are winding. Their smooth bends are called meanders, after the name of the river Big Menderes in Turkey. The flat streams do not penetrate deep into the surface of the earth and often spill over into flood waters, forming floodplains.
The mountain rivers are exactly the opposite. They have great speed, making their channels even, and the valleys are narrow and deep. They do not have wide floodplains and terraces. As a rule, the riverbed occupies the entire valley.
The rapids, canyons, waterfalls
Mountain rivers, as a rule, are formed in places where the foundation is composed of hard rocks. Grinding them and going deep, they form canyons and gorges, which, in fact, are valleys with steep slopes and a very narrow bottom. The longest canyon in the world is in Greenland and is hidden under a layer of ice. One of the deepest on the planet - the Grand Canyon in Arizona.
The uneasy mountainous terrain also contributes to the formation of rapids along the water. These are stones and small rocks that overlook the surface of the river, blocking the path of ships and boats. From erosion of rocks at the bottom of the channel sometimes form sharp ledges, from which the water does not flow, but literally falls. Such places are called waterfalls.The largest of them - Angel, Victoria, Niagara.
The rapids, canyons and waterfalls can be formed on the flat rivers, for example, Smotrychsky (Ukraine) and Reutsky (Moldova) canyons, Ben rapids on the Volga. However, they most often occur in mountainous areas.
Plain and mountain rivers of Russia
More than 2.5 million rivers and small rivers flow through the country. However, the large watercourses with a length of more than 10 kilometers are only 140 thousand. There are few classical mountain rivers among them, because many of them become flat during their way. Nevertheless, we can mention Terek, Samur, Kuban, Katun, Sulak as an example.
The southernmost of Russia's largest watercourses is the Kuban River. It begins on Elbrus in the Karachay-Cherkess Republic. Kuban is formed from the confluence of two other rivers - Ullukam and Uchkulan - and flows into the Sea of Azov. At length, it stretches for 870 kilometers, and the height difference from its source to the mouth is 1,339 meters.
The flat rivers of Russia are the Ob, Volga, Yenisei, Don. The longest in the country and one of the longest in the world is the Ob.