What Is a Drainage Area?

A watershed refers to a river catchment area surrounded by a watershed. There are two types of groundwater catchment and underground catchment. If the surface catchment area and the underground catchment area coincide, it is called a closed watershed; if it does not overlap, it is called a non-closed watershed. The so-called watershed usually refers to the ground catchment area.

A watershed refers to a river catchment area surrounded by a watershed. There are two types of groundwater catchment and underground catchment. If the surface catchment area and the underground catchment area coincide, it is called a closed watershed; if it does not overlap, it is called a non-closed watershed. The so-called watershed usually refers to the ground catchment area.

Chinese name

Watershed

Foreign name

drainage basin

Pinyin

liú yù

Definition

The area through which the main stream and tributaries of the water system flow

Russian

Features

Watershed area, river network density, etc.

Basic meaning of watershed

Each river has its own watershed,

Watersheds and river systems (People's Education Edition Senior High School Geography Compulsory 3 Figure 3.12) ^[1]

A large watershed can be divided into several small watersheds according to the level of the water system, and the small watershed can be divided into smaller watersheds. In addition, a section of the river can also be intercepted and divided into separate watersheds. The watershed between the watersheds is called the watershed, and the line connecting the highest points on the watershed is the watershed, which is the boundary of the watershed. Atmospheric precipitation at the highest point of the watershed will flow to the adjacent river or water system with the watershed as the boundary. For example, the surface water south of the Qinling Mountains in China flows to the Yangtze River system, and the surface water north of the Qinling Mountains flows to the Yellow River system. Watersheds range from mountains to plateaus to plains or lakes. The watershed in mountainous or hilly areas is obvious, and it is easy to draw a watershed on the topographic map. The watershed in the plain area is not significant, and it is difficult to draw the watershed using only the topographic map, and sometimes it is necessary to conduct field surveys to determine it.

Watershed area is an extremely important data in hydrogeographic research. Two or more regions with similar natural conditions, generally the larger the basin area, the more abundant the river's water volume in this region.

Watershed characteristics

Watershed characteristics include: watershed area, river network density, watershed shape, watershed height, watershed direction or main stream direction.

Watershed area: The area surrounded by the watershed's surface watershed and exit section. It is also called hydrocatchment area in hydrology, and the unit is square kilometers. This is one of the important characteristics of the river, and its size directly affects the river and the amount of water and the formation process of runoff.

River network density: The ratio of the total length of the main tributaries to the area of the river basin. The unit is km / km2. Its size indicates the density of water system development. It is controlled by factors such as climate, vegetation, landform features, and rock soil.

Watershed shape: It has a significant impact on changes in river water volume.

Basin height: It mainly affects the form of precipitation and the temperature in the basin, and then changes the water quantity in the basin.

The direction of the river basin or the main stream has a certain effect on the snow and ice ablation time.

Watersheds can be divided into inflow areas (or inflow basins) and outflow areas (outflow basins) according to whether the rivers eventually enter the sea.

Watershed citation explanation

Refers to the entire area through which the main stream and tributaries of a water system flow.

Chapter 8 of Du Pengcheng's "Protecting Yan'an": "The storm caught the thunder ... rolled across the Yellow River Basin that the Chinese nation has fought for thousands of years, and rushed away.

"Going into the Sun" by Yang Shuo: "The land on the banks of this big river is so rich that it was originally the rich granary of our motherland."