Drainage basins Flashcards
What is the definition of a Drainage basin?
The area of land drained by a river.
What is the definition of a watershed?
The edge of highland surrounding a drainage basin. It marks the boundary between two drainage basins.
What is the definition of the source?
The beginning or start of a river.
What is the definition of the confluence?
The point at which two rivers or streams join.
What is the definition of a tributary?
A stream or smaller river which joins a larger stream or river.
What is the definition of the source?
The point where the river comes to the end, usually when entering a sea.
What is overland flow?
Where water cannot infiltrate into the ground.
What is sheet flow?
When overland flow occurs over a large surface area, often after heavy rain.
What are Rills?
Where overland flow separates into small channels.
What is the definition of infiltration capacity?
The rate of infiltration.
What is the definition of field capacity?
The amount of soil moisture or water content held in the soil after excess water has drained away.
What factors affect the rate of infiltration?
Soil type
Amount of vegetation
Urbanisation
Antecedent weather conditions
Why is field capacity important?
A low field capacity (sand) contributes greatly to the risk of flooding. It affects the rate of infiltration, percolation and through flow.
