water balance Flashcards
1
Q
what is the water balance
A
inputs - outputs in a system
2
Q
give an example of a water system
A
drainage basin
3
Q
what are the usual outputs in a water system
A
potential evapotranspiration
4
Q
what is discharge
A
volume of water passing a measuring point in a given time(in river)
5
Q
how to measure dischange
A
area of river x velocity
6
Q
what does excess discharge cause
A
flooding
7
Q
what causes spikes in river discharge graphs
A
snow/ice melt
8
Q
physical influences which effect flooding
A
- size/shape of DB
-precipitation
-drainage density
-saturation
-rock permeability
-vegetation cover
9
Q
how does drainage density effect flooding
A
high conc of rivers within area = more water = more flooding
10
Q
human influences which effect flooding
A
-deforestation(agriculture)
-urbanization(concrete/tarmac)
-flood engineering
