The drainage basin system is the land based part of the hydrological cycle. A drainage basin is the area of land drained by a river. When water reaches the surface it may take a series of different routes to reach the river (see diagram below).
You will also need to learn about changes to the drainage basin system - for example what would happen if part of the drainage basin was to be built on? What would happen if trees were removed? etc.
|You must make sure that you learn the named features of a drainage basin!||
Source - the start of a river
Mouth - the end of a river
Tributary - a small river feeding the main river
Confluence - where two rivers meet
Watershed - the edge of a drainage basin