Rivers just keep on flowing without any stop. We humans exist because of rivers. Importance of Rivers cannot be stated in just few words. It is because they keep on doing their work silently. See, they are not equipped with social media to keep showcasing their work to the entire world!
Puns apart, what if the rivers dry up some day? May be only then we will realize their importance. Rivers provide us with fresh drinking water.
It is one of the biggest source of fresh water. As a result,we need to rely heavily upon the rivers for drinking water. There are various civilizations formed around rivers. These civilizations started near rivers because river plains had fertile soil which helps in cultivation.
Moreover they also helped in transportation. Rivers are not only important for human beings but also serves a great purpose to the animals and trees as well. There are various aquatic animals which breed in rivers. Moreover, various plants also grow in the rivers. They form a part of the ecosystem which is very important to maintain the balance in the food chain. Rivers are also a source of energy. It may be a lake, a larger river, or the ocean.
The largest rivers mostly empty into the ocean. The water in a flowing river works on the force of gravity which pulls the water downward. The steeper the river slope, the faster the river moves and gains more energy. The river carves and shapes the landscape using the power of its flowing water.
This process is called weathering or erosion. The Grand Canyon in the state of Arizona, U. The water movement in a river is called a current, which is usually the strongest near the source where rapids and waterfalls are very common. Storms can also increase the current. The river wears away rocks and soil along its bed and carries them downstream. Along with the swift current, the pieces that are carried in the moving water, scrape and dig into the river bottom, or bed.
The river usually carves a narrow, V-shaped valley. Coming to the lower land, the slope of the river course flattens. Instead of cutting bed deep, it starts to wind from side to side in looping bends. These are called meanders. This action also widens the river valley. At this stage, the river leaves behind solid materials, including the rocks , sand, it collected upstream, which is called sediment.
The sediment that gets deposited is called alluvium and contains huge eroded topsoil from upstream and the banks of its meanders. Therefore, the river deposits very fertile soil on its flood plain, the area next to the river and is subject to flooding.
The middle of a river is its deepest part called a channel. The current is often strong here to help transport larger ships. The river slows down and moves sluggishly near the end of its journey.
It has less strength to cut into the land, and carry a heavy load of sediment. It may deposit so much sediment where it meets the ocean or a lake, that it forms a new land called delta. Every river not necessarily has delta. There is no pure delta of Amazon as the strong tides and currents of the Atlantic Ocean prevent the accumulation of sediment.
Deltas usually have fertile soil like the deltas of Nile and the Ganges are the major agricultural land in Egypt and Bangladesh, respectively. The headwater can come from rainfall or snowmelt in mountains, but it can also bubble up from groundwater or form at the edge of a lake or large pond. The other end of a river is called its mouth, where water empties into a larger body of water, such as a lake or ocean.
Along the way, rivers may pass through wetlands where plants slow down the water and filter out pollutants. The water that flows in rivers is fresh, meaning that it contains less than one percent salt.
However, rivers still carry and distribute important salts and nutrients to support plant and animal life. For this reason, some of the most biodiverse habitats on our planet can be found around rivers.
Collectively, scientists estimate that all the rivers in the world carry about 3. Fast-flowing rivers carry pebbles, sand, and silt. As the river begins to slow down—as in a wetland, at the outside of a bend, or where the river widens, such as at the mouth—these sediments sink and build up to form deltas.
Rivers that overflow their banks also deposit sediment in the surrounding flood plain. These deltas and floodplains are highly fertile agricultural zones that offer tremendous value to the surrounding people. In Egypt, for example, the Nile River and its adjacent delta helped give rise to the Egyptian empire that built the pyramids. Humans use rivers for irrigation in agriculture, for drinking water, for transportation, to produce electricity through hydroelectric dams, and for leisure activities like swimming and boating.
Each of these uses can affect the health of a river and its surrounding ecosystems. Monitoring the health of rivers, lakes, and streams is important work that is conducted by scientists called limnologists.
Also called hydroelectric energy or hydroelectric power. The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit. The Rights Holder for media is the person or group credited.
Tyson Brown, National Geographic Society. National Geographic Society. For information on user permissions, please read our Terms of Service.
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