Drainage Basin 3.1.1.2

Question 1

What is a drainage basin

Answer 1

Open, local hydrological cycle

Areas that is drained by a river and it’s tributaries

Question 2

What’s the boundary of a drainage basin

Answer 2

The watershed as it separates basins

Question 3

Inputs of a drainage basin

Answer 3

Rain, snow, hail

Question 4

Outputs of a drainage basin

4

Answer 4

Evaporation, transpiration,evapotrainspiration, river discharge

Question 5

6 stores

Answer 5

Interception - temporary, precipitation on vegetation canopy of buildings
Vegetation - water taken up and stored in plants
Surface - water in ponds, lakes etc
Soil- moisture in soil
Groundwater - water in ground. Porous rocks hold water - aquifers
Channel - water ina river or stream

Question 6

10 flows

Answer 6

Infiltration
Overland/run off
Throughflow 
Stem flow 
Throughfall
Percolation
Groundwater flow
Base flow - groundwater flow that feeds into river through river banks 
Inter flow - water flowing downhill through permeable rock
Channel flow

Question 7

What is a water balance
What does it affect
Formula

Answer 7

Balance between inputs and outputs
Affects how much water is stored in basin

P= Q+ E +- S

Q - discharge
E - evpotranspiration
S - changes in storage

Question 8

Rivers regime

Answer 8

Annual pattern of a river, with discharge levels rise and fall

Question 9

6 parts of soil moisture graph and axis

Answer 9

Soil misfire recharge
Utilisation
Deficit
Surplus

Precipitation line
Potential evapotranspiration line

Precipitation
Month

Question 10

What’s a hydrograph / flood hydro road

Answer 10

Graph to show discharge of a river

Flood - show discharge leading up to and after rainfall event

Question 11

What’s river discharge

Answer 11

Volume of water that flows in a river per second measured in cubic meteres per second

Question 12

8 parts of hydrographic

And axis

Answer 12

Lag time
River I flood
Peak discharge 
Peak rainfall
Base flow
Rising limb
Falling limb
Bankfull discharge 

Rain , time , discharge

Question 13

Factors affecting hydrographic shale and run off

4 physical

Answer 13

Size of basin - larger catches more precipitation- higher peak discharge as larger distance to travel

Shape - circular = more flashy . All pints on watershed roughly same distance from point of discharge - more water reaches same point at same point

Steepness - water flows faster dounhill - shorten lag time

Rock and soil type - impermeable doesn’t store water - increases run off and peak discharge

Question 14

Factors affecting hydrographic and run off

4 human

Answer 14

Deforestation - reduces interception and infiltration rate - rapid overland flow and flashy hydrograph. Also soil exposure - increased erosion - sedimentation of channel - reduces bankfull capacity - increased flood risk

Afforestation - oppose effect

Agriculture

Growth of urban areas - flashy due to impermeable surfaces