Task Sheet: Drainage Basins
Drainage Basins
1. Define the term drainage basin.
2.
Explain why the hydrological cycle of a drainage basin is considered to be an open system.
3.
Define the terms inputs, stores, transfers and outputs of the drainage basin.
4.
Produce a table to illustrate the inputs, stores, transfers and outputs of the drainage basin.
5.
Use the diagram below of a forest drainage basin and the table of terms to construct a flow
diagram, using a series of boxes and arrows, to describe how water is transferred from the
atmosphere into the river channel. Use a colour – coding system to separate inputs, stores,
transfers and outputs. Next to each term add a phrase to explain what is happening.
precipitation
infiltration
evaporation
surface storage
transpiration
water table
percolation
interception
overland flow
soil storage
throughflow
baseflow
groundwater storage
throughfall
evapotranspiration
groundwater storage
6.
Then annotate your diagram to describe the relative speed that each transfer moves water to
the river channel.
7.
Explain how your flow diagram will be different in the winter if the drainage basin was covered
by deciduous trees.
8.
Consider how the drainage basin hydrological cycle would be different for an urban drainage
basin. Work in pairs to draw a flow diagram similar to the one for a forested drainage basin.
But, you should include the following in your diagram; houses, impermeable tarmac and concrete
surfaces, and underground grains and sewers.
9.
Describe and explain how stores and flows might differ from that of a forested drainage basin
10. Answer the following questions below.