Rivers are the general name of large natural water flows on the earth's surface. The grooves produced by crustal movement will form rivers of different sizes under the condition of precipitation and groundwater supply. We often praise the Yellow River as our mother river. Writers and poets at all times and in all countries have given high praise to the river with their own pens.
Rivers are closely related to human life, because they are widely distributed, have large water volume, have the shortest cycle, and most of them are exposed to the surface, so they are very convenient to use. It is conceivable that rivers are the main source of fresh water that human beings depend on. In addition, rivers also play an important role in shipping, irrigation, aquaculture and tourism. Although the flood also brings the loss of human life and property and the destruction of ecological environment, it is still insignificant compared with the benefits it brings to mankind.