Processes in a Drainage Basin
Geography: Cambridge International GCSE (2027 Exams), topic 1.6.2
Processes in a Drainage Basin
Key hydrological processes in rivers and drainage basins include precipitation, interception, infiltration, percolation, throughflow, groundwater flow, transpiration, evaporation, and evapotranspiration.
Precipitation and interception
- Precipitation delivers water to drainage basins as rain, snow, sleet, or hail.
- Interception occurs when vegetation or surfaces catch precipitation, delaying its reach to soil.
Infiltration and percolation
- Infiltration is the process of water entering the soil from the surface.
- Percolation follows infiltration as water moves deeper through soil layers into rock.
Throughflow and groundwater flow
- Throughflow moves water laterally through soil towards river channels.
- Groundwater flow involves the slow movement of water in rock layers beneath the soil.
Evaporation and Transpiration
- Evaporation is when water from surfaces move back into the atmosphere.
- Transpiration is the process where plants release water vapor into the air from their leaves.
Evapotranspiration
- Evapotranspiration combines evaporation and transpiration to move water back into the atmosphere.
Overland flow and channel flow
- Overland flow is water that moves over the land surface after heavy rain.
- Channel flow is water moving in rivers and streams within defined channels.
Test yourself on Processes in a Drainage Basin
What process follows infiltration as water moves deeper through soil layers?