Rivers

Question 1

What is the definition of source ?

Answer 1

The place where the river begins

Question 2

What is the definition of tributary ?

Answer 2

A stream or river which joins a larger river

Question 3

What is the definition of mouth?

Answer 3

The place where a river enters the sea

Question 4

What is the definition of estuary ?

Answer 4

That part of a river mouth which is tidal

Question 5

What is the definition of river basin?

Answer 5

All the area of land drained by a river and it tributaries

Question 6

What is the definition of watershed ?

Answer 6

The high ground which separates one river basin from another

Question 7

What is the definition of confluence?

Answer 7

The place where two or more rivers meet

Question 8

What is the definition of course?

Answer 8

The route taken by a river between its source and its mouth

Question 9

What are the 3 river proceses ?

Answer 9

Erosion , transportation , deposition

Question 10

What are the the proceses of erosion

Answer 10

Hydraulic actions , abrasion , solution , attrition

Question 11

What is erosion ?

Answer 11

Erosion wears the land down and carries the pieces away

Question 12

What is hydraulic actions ?

Answer 12

Hydraulic action is the force of fast-flowing water that breaks up the bed and banks of the river, almost like a power hose

Question 13

What is abrasion ?

Answer 13

Abrasion is when stones carried by the river (Load) hit against the bed and banks of the river , wearing it away

Question 14

What is solution?

Answer 14

Solution is when river water dissolves the rocks over which it flows

Question 15

What is attrition?

Answer 15

Attrition is when stones carried roll along the bed or collide with each other. River stone become round and smooth over time

Question 16

What are the processes of river transportation?

Answer 16

Suspension , solution ,traction , saltation

Question 17

Why does a river deposit its load? (Deposition)

Answer 17

The river looses its speed and energy , because the gradient (slope) is almost flat.
Its volume decreases in the summer due to evaporation.
River deposition is useful because river mud , called alluvium , is a fertile soil , this helps farmers by making their fields more fertile

Question 18

What is a river load ?

Answer 18

This is all the material a river transports e.g. rocks , pebbles , silt , sand , mud , clay

Question 19

What are the creatures formed in the youthful stage ?

Answer 19

V-shaped valley (erosion)
Interlocking spurs (erosion)
Waterfalls (erosion)

Question 20

What features and formed in the mature stage ?

Answer 20

Meanders (erosion + deposition)
Ox-bow lake (erosion + deposition)

Question 21

What features are formed in the old stage?

Answer 21

Levees ( deposition)
Floodplain (deposition)
Delta (deposition)

Question 22

What is transportation?

Answer 22

Transportation is the process by which rivers carry materials as they flow

Question 23

What is deposition ?

Answer 23

Deposition is the processes by which a river drop or deposits the material (load) it is carrying

Question 24

What features are formed due to erosion ?

Answer 24

V-shaped valley , waterfall , interlocking spurs , meanders , ox - bow lakes

Question 25

What features are formed due to deposition?

Answer 25

Levees , floodplain , delta , meanders , ox-bow lakes

Question 26

What is the process of one feature formed by the process of deposition ?

Answer 26

Levees are raised banks found along the old of rivers and help prevent flooding. They develop through the process of deposition. During heavy rainfall or snowmelt flooding occurs , the river water level rises and overflows its banks. As the floodwater spread out , it slows down losing energy and dropping the heaviest sediments closet to the banks. Over time , repeated flooding deposits more and more sediment , gradually building up raised embankments. Lighter materials like silt and clay are carried further away, helping form fertile floodplains beyond the levees.

Question 27

What ae three ways rivers are important to humans ?

Answer 27

HEP (hydroelectric power) - rivers are used to generate electricity by building dams that harness the energy of flowing water. Example include the Hoover Dam in the USA. Transport - rivers serve as natural highways for boats and ships , allowing for the movement of goods and people. Historically , major cities developed along river for his reason. Sport nd recreation - rivers are used for activities like fishing , kayaking , rafting and swimming , providing leisure opportunities for local communities and tourists

Question 28

What are two positive impacts of dams ?

Answer 28

HEP generation - provides renewable electricity , reducing fossil fuel reliance Water supply and irrigation - ensure stable water access for drinking , farming and industry

Question 29

What are two negative impacts of dams?

Answer 29

Displacement - flooding forces communities to relocate. Environmental damage - alters ecosystem , disrupts fish migration and causes erosion. Salmon migration is affected. Eg. The Ardnacruha Dam , river Shannon , Co.Clare

Question 30

Why has flooding increased ?

Answer 30

Population growth - more people are living in towns built along rivers Building on floodplains - county council have allowed construction of housing estates on floodplains. Heavier rainfall due to climate change Clearing of tress for houses and farmland- tree would have absorbed the water from rainfall , much of which now runs-off into rivers

Question 31

How can we reduce flooding ?

Answer 31

Dredge silt from the bed of rivers - this will prevent the river from bursting its banks Don’t build on floodplains Reforestation - plant more trees which will absorb rainwater during heavy downpours

Question 32

What is the process of one feature formed by the process erosion ?

Answer 32

Water falls form at the youthful stage of a river due to differential erosion , where silt rock erodes faster than hard rock. Hydraulic action is the main force , with moving water wearing away the softer rock , while abrasion uses the rivers load to further erode the bed and banks , shaping the plunge pool. As the river carries its load over the fall it deepens the plunge pool. Solution erodes the back wall , creating an overhang of hard rock than eventually collapses into the plunge pool. This process repeats , causing the waterfall to retreat upstream forming a gorge through headward erosion.

Question 33

Name six ways humans use rivers?

Answer 33

HEP ( hydroelectric power) Transport Water supply Irrigation Fertile floodplains Sport and recreation