Geography Y08 Autumn 2023/24 Rivers Flashcards
1.1 hydrological cycle
The continuous movement of water between the land, the sea and the air.
1.2 evaporation
Water changes state from liquid to gas.
1.3 transpiration
Water vapour enters atmosphere through plants.
1.4 condensation
Water changes state from gas to liquid.
1.5 interception
Water is stored on leaves and branches of vegetation.
1.6 throughflow
Water flows through the soil into the river.
1.7 infiltration
Water seeps into soil.
1.8 groundwater flow
Water flows through the rock into the river.
1.9 surface runoff
Water flows over the land into the river.
1.1 permeable
Rock that lets water seep through it.
1.11 precipitation
rain, snow, sleet or hail
1.12 drainage basin
The area drained by a river and its tributaries.
1.13 watershed
The boundary of a drainage basin.
1.14 source
The beginning of a river and the point furthest from the mouth.
1.15 channel
The normal route a river follows.
1.16 tributary
A stream or river adding to a larger river.
1.17 confluence
The point where a tributary joins a river.
1.18 mouth
The point where a river enters the sea (or lake).
1.19 erosion
Wearing away of material.
1.2 transport
The carrying away of material.
1.21 deposition
When rivers drop load.
1.23 hydraulic action
The action of water pressure in breaking the rock.
1.24 abrasion
The load in the water scrapes away at the rock.
1.25 solution
The dissolving of rock by minerals in the water.
1.26 attrition
How rocks and stones get worn away by banging against each other.
1.27 traction
Large rocks roll along the river bed.
1.28 saltation
Smaller rocks bounce along the river bed.
1.29 suspension
Small particles float in the water.
1.3 solution
Transport of dissolved load.
1.31 hard engineering
Working against a river’s natural processes to prevent floods.
1.32 soft engineering
Working with a river’s natural processes to prevent floods.
2.1 v-shaped valleys
Vertical erosion erodes the land vertically à valley sides collapse due to gravity and weathering à V – shaped valley
2.2 waterfall/gorge
River flows over hard and soft rock à vertical erosion causes undercutting of soft rock à overhang/cap rock à collapses into plunge poolà process repeats à gorge
2.3 meanders/oxbow lakes
Lateral erosion on outer bend of river à deposition on inner bend à meander widens à process repeats à meander neck gets narrower àflood à oxbow lake
2.4 levees
River floods à deposition occurs on floodplain àlargest material dropped first à lightest further away à levee
3.1.1 deforestation
Removal of trees reduces interception adding more water to rivers. Soil is eroded filling channels and reducing volume.
3.1.2 urbanisation
The building of towns stops infiltration and increases surface runoff (sometimes worsened by drains) into rivers.
3.2.1 relief
Steep hillsides encourage rapid surface runoff which overwhelms river channels.
3.2.2 geology
Impermeable rock encourages rapid surface runoff which overwhelms river channels.
3.2.3 precipitation
Precipitation – lots of rain in a short time can cause floods when there is more surface runoff. Precipitation over a long period can cause soil to be waterlogged and groundwater to return to the surface.
4.1.1 dams and reservoirs
Large walls built across rivers to store water.
4.1.2 channel straightening
Removing meanders to speed river flow.
4.1.3 embankments
Raised walls to increase channel volume.
4.1.4 flood relief channels
Secondary routes for river water to follow.
4.2.1 flood warnings
Information to enable people to take action.
4.2.2 preparation
Modifications to buildings and putting plans and stores in place.
4.2.3 flood plain zoning
Restrictions on development on flood plains.
4.2.4 river restoration
Returning a river to a natural state to slow water.
5.1 Place
A portion of geographic space that is unique in some way and can be compared with other places
5.2 Physical & Human processes
Human or physical mechanisms of change such as migration or sea-level rise
5.3 Environmental impacts
The effect that people and/or natural occurrences have on the environment and our surroundings