Drainage basin: seneca Flashcards
what is orographic precipitation?
when air masses rise over mountains causing it to condense and rain.
what is frontal precipitation?
when two air masses meet at an area of low pressure creating rain.
what is convectional precipitation?
rainfall caused by water turning to water vapour due to solar radiation.
three output’s in a drainage basin
evaporation
transpiration
channel flow
flows of a drainage basin
interception
infiltration
direct runoff
saturated overland flow
through flow
percolation
groundwater flow
what are the physical factors that affect the drainage basin?
soil type
vegetation cover
rock type
climate
relief of the land
why does soil type affect the drainage basin?
impermeable soils can stop infiltration and lead to surface over saturation so increased surface runoff
when there is permeable soil, infiltration and percolation can happen so groundwater can recharge
why does vegetation cover affect the drainage basin?
higher coverage of vegetation the interception and evapotranspiration increases while surface runoff decreases
why does rock type affect the drainage basin?
some are impermeable so stop infiltration of water into the ground which can cause the ground to saturate and lead to surface runoff and increase flows in rivers
permeable rocks in contrast allows for infiltration and percolation to happen
why does climate affect the drainage basin?
cold climate = more precipitation falling as snow so water can be stored until it is thawed
may reduce the channel flow during the winter but lead to an increase during the spring and summer months due to glacial melt water
why does relief of the land affect the drainage basin?
steeper slopes, faster surface runoff, shorter times for water storage
what is abstraction?
Abstraction is the process by which humans remove water from underground water stores
do soils and rocks that are impermeable stop?
infiltration
