Diagrams & Graphs

Question 1

Answer 1

Hjulström curve

Key features:
- Critical erosion velocity curve
- Settling or fall velocity curve
- Zones

Question 2

Answer 2

Hydrograph

Key Components:
- X-axis (Time): Usually in days or hours after a rainfall event.
- Left Y-axis (Rainfall in mm): Shown with vertical bars.
- Right Y-axis (Runoff / River Discharge in cumecs): Shown with the blue curve

Labels:
- Peak Precipitation
- Lag Time
- Rising Limb
- Peak Flow / Peak Discharge
- Bankfull Discharge
- Storm Flow (Quickflow)
- Baseflow
- Falling Limb (Recession Limb)

Question 3

Answer 3

Bradshaw model

Question 4

Answer 4

Connection circle

Question 5

Answer 5

Fertility-rate line chart

Key words:
* Fertility rate: average number of births per woman
* Plateau / Stabilization
* sharp/gradual/rapid

Question 6

Answer 6

Population pyramid

• Youth-heavy / youthful population
• Ageing population (if the top is wider)
• Stable / Expanding / Contracting pyramid shape
• Dependency ratio (especially child vs. working-age)
• Working-age population (ages ~15–64)
• Elderly dependents / Youth dependents