By definition, a river is a water stream that flows in the riverbed itself. What makes rivers constantly move? It's simple - gravity or gravity forces the masses of water to move from a point with a greater absolute height to places with a lower altitude.

Now imagine a conditional container filled with water, in which there will be a perfectly flat bottom. In this case, there will be no movement of water masses in it. A life example is the pools of various sizes, in which waves and currents are created only artificially. But on the ubiquitous undulating surface of the land, which causes water level fluctuations, the liquid simply must move - flow from place to place.

So, the dynamics of water masses is caused by differences in land heights and the difference in liquid levels “resulting” from this. As a result of such movements, the same permanent streams appear - rivers. In addition to the main factor, there are several more that affect the rate of flow of water in a particular reservoir.

Factors affecting the course of the river

The inflow of additional water masses, for example, in the form of tributary, increases the speed and power of the main stream. The filling of the river with water directly affects the quality of its movement.

The wind, especially constant, if the direction coincides with the direction of the river, can increase the flow velocity of the surface layers of the water mass.Naturally, the directional movement of air masses in the opposite direction can slightly slow down the course of the surface layers of water in the river.

The difference in the density of water masses, caused by the presence of suspended particles in them, stimulates the buildup of the flow velocity between different flows within the same reservoir.

The difference in water temperature of different flows within the same river stimulates the appearance of new currents or an increase in the speed of existing ones.

Separate attention is required by a factor - a feature of the terrain along which the river flows. Indeed, at the global level, it is precisely the difference in heights that forms the flow. Plain rivers move much slower than mountain ones. A narrow mountain valley such as a gorge or canyon stimulates the increase in the velocity of the river.

River work

All rivers, moving to a minimum - the mouth of another river, the "body" of the lake, sea or ocean, do the work.

Destruction or erosion

Once on Earth, river valleys did not exist at all. But the crystallization of water masses and their natural movement from top to bottom caused the appearance of the first river valleys. Expression - water sharpens a stone, has a deep geographical meaning. During their movement, the rivers began to destroy the rocks along which flowed - both in depth and in breadth. The consequence of the flow of rivers became river valleys. One of the most striking examples is the canyon of the Colorado River, worked out by the river itself in the soft rocks of the Colorado Plateau - limestones, shales and sandstones, to a depth of 1800 meters.

Transport work

Washed river rocks transport downstream. The more suspended particles the water drags along, the lower the flow rate becomes. The classic of the genre is the Yellow River, which in a year carries 1.3 billion tons of particles “washed” by it on the Loess Plateau into the Yellow Sea.

Creation

In addition to the already mentioned mountain valleys, shallows and deltas form from the destroyed and taken-up suspended particles of the river. The most famous is the Nile Delta, which the river created from the particles of destroyed rocks brought out from the heart of Africa by it.