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What is the river bed? Channel processes and formation

What is the river bed? On what parts (segments) is it divided? What forms of relief form within the river channel?

Each of us knows perfectly well what the river looks like and its course. It can be narrow or wide, shallow or deep, permanent or temporary. What is the riverbed in terms of science? The answer to this question you will find in our article.

What is the channel: the definition and essence of the concept

The river is a water stream of natural origin, which is relatively large in size. And every river in the world has a riverbed. What is it?

Hydrologists can tell what the riverbed is like. These are scientists who are engaged in the study of a variety of water bodies. Not only rivers, but also lakes, marshes, reservoirs, etc. But only the rivers have what we are going to consider in detail in this article. So, what is the channel?

Rusl is called the gutter on the surface of the earth, along which the flow of water flows. This is the most degraded element of the river valley. It should be noted one important point: the river bed, being the basis and the "foundation" for the river, is formed by it.

Rusla can vary greatly in appearance and size. Large rivers (such as the Volga, the Dnieper or the Amazon) can have a width of several kilometers. At the same time, the channel of shallow watercourses and streams can easily jump. In plain rivers, the channel is usually meandering and multi-hose, and in the mountain rivers - more direct and heavily cluttered with rocks, boulders, tree trunks.

So, we figured out what a channel is. Now find out how it changes the terrain of the surrounding area.

Channel processes and their features

To better understand the question of what a channel is, you should familiarize yourself with the processes that occur in it.

Under channel processes, the whole set of processes and phenomena that ultimately lead to a change in the shape and parameters of the river channels is meant. For the first time they were engaged in research in the Middle Ages. So, the well-known Italian scientist Galileo Galilei worked on the project of straightening the bends of the Tiber in order to reduce the level of floods that flooded Rome every year. Today, channel processes are being studied by a special scientific discipline - the study of local studies.

The basis of these processes is the interaction of the current water and the underlying surface. The river destroys rocks, transports them to certain distances and stores (accumulates) in a new location. As a result of these processes, the river valley itself is modified and takes on new forms.

The riverbed of hydrologists is usually divided into three parts (segment):

  • Upper current (destructive processes dominate here);
  • Mean current;
  • The lower current (here the processes of accumulation of the geological material destroyed in the upper reaches of the river prevail).

Man has learned to significantly modify river channels. Active anthropogenic intervention allows to change their form (for example, to straighten water streams), depth and even direction. All this, of course, can not but affect the dynamics of natural channel processes.

Channel formations: fords, plaes, ruts and waterfalls

As a result of the mechanical operation of the river bed, a number of specific formations and forms of relief are formed:

  • ford;
  • Sastruga;
  • Ples;
  • Roll;
  • threshold;
  • Waterfall and others.

The ford is a shallow stretch on the riverbed along which the river can be crossed on foot or on a vehicle. In the Middle Ages, large fords often spawned whole cities. Today, many names of settlements are associated with this term: for example, the city of Brody in Ukraine, Havlickuv Brod in the Czech Republic, Oxford in the UK (ford is translated from English as "ford").

Sastrugi called elongated sand or sand and pebble scythes, located under water. Plyos is a deep section of the river channel, which forms near the concave shore of the meander.

The riverbed of mountain rivers and rivulets is very often complicated by rapids, gushers and waterfalls. Thresholds are formed in those places where very hard rocks are emerging on the surface, which the river can not erode and destroy. The waterfall is a unique geomorphological formation, a rocky ledge in the riverbed from which water freely falls down.

Bifurcation of the river bed

Bifurcation of the river is an interesting and rather rare natural phenomenon. The term itself comes from the Latin word bifurcus, which means "bifurcated". Bifurcation is the division of the riverbed (including the river valley) into two separate water streams. In the future, these streams no longer connect and flow into different reservoirs. Most often this phenomenon is observed on flat rivers, which flow along a flat, leveled earth's surface.

The most famous example of the bifurcation in the world is the Orinoco River in South America. In the upper current, the sleeve of Kasikyare branches off from it. Later it adjoins the river system of the Amazon, taking with itself about a third of the entire runoff of the Orinoco.

Finally…

What is the river bed? The definition of this concept and its detailed study is one of the tasks of the science of hydrology. The riverbed is one of the main elements of the river valley, a natural trough, along which the water flow directly moves.

In the riverbed, processes of destruction, migration and accumulation of geological material are constantly occurring. As a result of these processes, specific microforms of the relief are formed: fords, sastrugi, plesas, rapids, rapids and waterfalls.

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