Riverd 😀😀 Flashcards
What is the source of a river?
The river’s starting point
What’s a river’s course?
The path it takes from the source to the sea.
What is a river’s mouth?
The point where it reaches the sea.
What is a drainage basin?
An area of land that is drained by a river and its tributaries
What is a watershed?
High land separating two drainage basins
What is a tributary?
Small streams that join the river
What is a confluence?
The meeting point of two rivers
What is a meander
A bend in the river
What is floodplain?
Area beside rivers that’s covered with floodwater during times of heavy rain
What’s the estuary?
Near the sea, the part of the river affected by tides.
What is a levee?
A raised bank formed by the river.
What are the three main things rivers do?
Erode, transport and deposit.
What are the 4 processes of erosion?
Hydraulic action
Abrasion
Solution
Attrition
What is hydraulic action?
When fast flowing water breaks down the river’s banks and beds.
What is abrasion?
When the river’s load hits against the beds and banks, wearing it away.
What is solution?
When river water dissolves the rock over which it flows.
What is attrition?
When stones in the river hit against each other and become smooth.
What are are the four processes of river transport?
Traction
Saltation
Suspension
Solution
What is traction?
Larger stones are rolled or dragged along the river bed
What is saltation?
Lighter stones are hopped along the river bed,
What is suspension?
The smallest rocks and grains are help up in the water, making the river cloudy.
What is solution? (Transport )
Rock is dissolved in the water, maybe colouring it.
What is river mud?
Alluvium.
What is an example of alluvium in floodplain being used?
The River Ganges, India
What are the three stages of a river?
Youthful stage
Mature stage
Old stage
What is the youthful stage like?
It’s fast flowing, steep, little water, lots of erosion
What is the mature stage like?
It’s slower, more water, still eroding, more deposition.
Whats the old stage like?
It’s slow, loads of water, mainly deposition, little erosion.
Name 3 landforms from the youthful stage
Waterfalls,
Interlocking spurs,
V-shaped valleys
Name an example of a waterfall in Ireland
Powerscourt, Co.Wicklow.
What is a waterfall?
Sudden drops in the river’s course
How does the river erode when forming waterfalls?
Vertical erosion.
What forms after a waterfall occurs quickly?
A steep sided gorge
What is an example of V-shaped valleys and interlocking spurs?
The River Suir
What are V shaped valleys?
Grooves in mountainsides made by young rivers.
What are interlocking spurs?
Small ridges of land that stick out in the path of the river down a mountain.
What are three landforms found in the mature stage?
Meanders,
Ox bow Lakes,
Floodplain
What’s an example of where you can find meanderers and OxbowLakes?
River Moy
What are meanders?
S shaped bends in a river
What are oxbow Lakes?
Horseshoe shaped lakes
What are meander and Oxbow Lakes formed from?
Erosion and deposition
What type of erosion and direction of erosion forms meanders?
Hydraulic action and abrasion through lateral erosion
Where does deposition occur in meanders?
Deposition occurs on the inside bend
How do meander scars form?
When an oxbow Lake dries out
What’s an example of where you can find floodplain?
The mature stage of the river Shannon.
What are two landforms that can be found in the old stage of a river?
Levees and deltas
What is a levee?
A long bank of stones and alluvium that firms beside a river
What process are levees formed by?
They are formed by deposition.
Where can you find levees.
The river Moy County Mayo.
Where can you find Deltas?
The Nile Delta and Mississippi Delta
What is a Delta?
Delta is an area of land deposited at the mouth of a river
What process are Delta formed by?
Deposition
Name six ways people use rivers
hydroelectric power
Transport
Water supply
Irrigation
Fertile floodplain
Sport and recreation
What is hydroelectric power?
When green energy is formed by harnessing the energy from flowing water through dams.
How are rivers used as transport?
They are used as natural highways for boats and ships
How do people use fertile floodplain?
Farmers build farms, neon floodplain so that when flooding occurs they receive aluminium
Where is fertile floodplain use common?
The Nile river Valley
What’s an example of a dam where hydroelectric power is harnessed?
The Hoover Damm in the USA
What are two positive impacts of dams?
They can be used for HEP, and water supply.
What are two negative effects of dams?
Displacement and environmental damage
How do dams displaced citizens?
Flooding forces communities to relocate
What is the environmental impact of dams?
They alter ecosystems and disrupt fish migration. They also stop the spread of alluvium.
Name four reasons why flooding has recently increased
Population growth
Building on flood Plains
Clearing trees for building
Heavier rainfall due to climate change
How does population growth affect current flooding?
More people are living in town built along rivers
How does the clearing of trees affect flooding?
Because trees would’ve absorbed excess rainfall
Name three ways on how to reduce flooding
Dredge silt from river beds
Don’t build on floodplains
Reforestation
How would silt dredging reduce flooding?
This would prevent the river from bursting its banks.
