The school curriculum takes a course to study the water system of our planet. One of the important topics are rivers. Their value is quite large. We can say that it is thanks to their waters that life on land is possible. They shape the climate, vegetation, wildlife, and more. Numerous cities receive electricity, which is generated at the constructed hydroelectric power stations.
In this article, I would like to understand in detail what a river floodplain is. To study the definition of this part of the watercourse. It is also very important to know what species it happens. So, let's get started.
Definition
A floodplain of a river is a section of a valley along the direction of a water stream that is periodically flooded. Basically, this phenomenon occurs during floods, as water in the channel does not fit.
Floodplains are usually formed near rivers that flow on the plain; floodplains can also be found in the mountains, but less frequently. During floods, this area is periodically flooded. The floodplain is trimmed with terrace ledges, sometimes it is located in separate clusters from different sides of the channel.
Varieties by size
The floodplain of the river can be divided into two types: low and high. These names speak for themselves: the classification takes place according to certain dimensions.
The high floodplain reaches from 5 to 15 m in height, and the low - only from 0.5 to 2 m. The latter, as a rule, is often flooded. High is covered with water at more abundant floods. Their width can vary from 10 meters to several kilometers. It is also worth noting that the floodplain of the river has the feature of either increasing or decreasing in size. When expansion occurs, sleeves are formed, and on narrowed areas of the valleys, the flow rate increases and erodes the channel. Such cases are characteristic of mountain rivers.
Classification by type
The floodplains are divided into 5 types:
- segmented;
- one-sided;
- terraces;
- boned;
- delta.
The formation of a segment floodplain is associated with the meandering of the river itself, as well as its division into segments that are located on both edges of the channel.
Watercourses with a tendency to shift in one direction usually have one-sided floodplains. This area stretches along the channel for tens of kilometers. It can also diverge into different sections of the sleeves.
The near-terraced floodplain is located in the lower part of the relief, sometimes it is overgrown with urea (shrubs or forest in the floodplain of the river). When small water currents carry thin weight material, it slowly settles in the floodplain. The surface is often perfectly flat.
The bunded floodplain is formed due to an increase in the height of the river banks. As a rule, this occurs in direct places of the river on different sides. Since the stream practically does not change its location, the shafts form dams that are located above the floodplain. They can be found among the course of the Dnieper, Amu Darya, in the lower reaches of the Kura.
The delta floodplain of the river is the widest and most even, its surface does not change. Sometimes it is divided by a network of lakes, streams and swamps.
Floodplain lands are valuable lands that can be used to develop livestock and hay meadows. They are also used to grow crops that need high hydration, such as fodder herbs, vegetables and various fruits. This is not suitable for sowing cereals, as they need zonal soil.