Key Terms for River Landscapes in the UK

abrasion

rocks scrape and wear away the river bed and banks

attrition

rocks hit each other, breaking into smaller, rounder particles

hydraulic action (corrasion)

force of water traps air in cracks, weakening and breaking the bank

vertical erosion

downward erosion that deepens the river channel (upper course)

lateral erosion

sideways erosion on the outside of meanders, widening the valley

traction

large rocks roll along the river bed

saltation

small stones bounce along the river bed

suspension

fine particles carried within the water

solution

dissolved minerals carried in the water

meander

a bend in a river

ox-bow lake

a horseshoe-shaped lake cut off from a meander

interlocking spurs

ridges of land that rivers wind around in the upper course

waterfall

sudden drop where soft rock erodes faster than hard rock

gorge

narrow, steep valley formed as a waterfall retreats upstream

flood plain

flat land beside a river that floods regularly

levee

raised river bank made form deposited sediment (natural or artificial)

estuary

tidal mouth of a river where it meets the sea

long profile

the gradient of a river from source to mouth

cross profile

side-to-side shape of a river valley or channel

hydrograph

graph showing river discharge over time after rainfall

discharge

volume of water flowing past a point per second (m³/s)

precipitation

water falling from the atmosphere (rain, snow, hail, sleet)

fluvial processes

erosion, transport, and deposition by rivers

flooding

when river discharge exceeds channel capacity

flood risk

likelihood of flooding in an area

flood warning

advance alerts that allow people to prepare or evacuate

flood plain zoning

using land based on flood risk (high risk = open land)

flood relief channel

artificial channel that carries excess water during floods

soft engineering

flood management using natural processes; cheaper + sustainable

hard engineering

man-made structures (concrete/steel) to control rivers

dam & reservoir

barrier across a valley creating a lake to store and control water

embankments

raised river banks that increase channel capacity

channel straightening

removing meanders so water flows faster and reduces flooding risk