Keywords - Rivers

Question 1

Precipitation

Answer 1

Rain, hail, sleet or slow which falls into the drainage basin

Question 2

Surface Store

Answer 2

A place on the surface where water is stored. (e.g Lakes)

Question 3

Interception

Answer 3

The prevention of water from reaching the soil by vegetation

Question 4

Transpiration

Answer 4

Loss of water through a plant

Question 5

Infiltration

Answer 5

The downward movement of water into the soil surface

Question 6

Evaporation

Answer 6

The transformation of water droplets into water vapour

Question 7

Overland Flow

Answer 7

The movement of water over the surface when the precipitation is too intense for the soil to absorb or the grounded is frozen or already saturated.

Question 8

(un) Saturated Rock

Answer 8

Rock that is (not) full of water and cannot hold more

Question 9

Percolation

Answer 9

The downward movement of water into the bed-rock

Question 10

River Channel

Answer 10

The channel in which the river flows.

Question 11

Groundwater Flow

Answer 11

The sideways movement of water through the rock layer.

Question 12

Groundwater Store

Answer 12

The storage water in underground, permeable rock.

Question 13

Water Table

Answer 13

The divider between the unsaturated and saturated rock.

Question 14

Pipe Flow

Answer 14

A form of throughflow through natural pipes in the soil (such as worm holes)

Question 15

Throughfall

Answer 15

When water drips of leaves (leaf drip) after interception

Question 16

Stomata

Answer 16

Tiny pore spaces on leaves through which transpiration takes place

Question 17

Channel Flow Output

Answer 17

Water leaving the system through the river channel.

Question 18

Water Surplus

Answer 18

In the winter months there is more water than is being used, resulting in excess water in the ground.

Question 19

Utilisation

Answer 19

When evapotranspiration exceeds rainfall in the summer months and water is being used up.

Question 20

Soil Moisture Recharge

Answer 20

After the summer months, rainfall exceeds evapotranspiration and the ground is filled back up with water.

Question 21

Field Capacity

Answer 21

The maxiumum amount of water the soil can hold.

Question 22

Abrasion

Answer 22

Scraping and scouring of rocks against the river bed which cause erosion.

Question 23

Hydraulic Action

Answer 23

The sheer power of the water removes loose material and erodes the river channel.

Question 24

Corrosion

Answer 24

Rocks such as Limestone are eroded by the acidity of the water.

Question 25

Attrition

Answer 25

When rocks strike one another and become smoother, smaller and more rounded

Question 26

Traction

Answer 26

When rocks are moved along the river bed by rolling along.

Question 27

Saltation

Answer 27

When smaller particles in the river bounce along the riverbed.

Question 28

Suspension

Answer 28

When fine particles are held in the river and are moved by the flow of the water.

Question 29

Solution

Answer 29

When particles are dissolved in the water and are moved by the flow of the water.

Question 30

Competence

Answer 30

The diameter of the largest particle a river can carry for a given velocity. Increases to the sixth power of its velocity.

Question 31

Capacity

Answer 31

The amount of material a river can carry (the total volume of the load). Increases to the third power of its velocity.

Question 32

Lateral Erosion

Answer 32

Erosion that takes place sidewards in the middle and lower courses.

Question 33

Vertical Erosion

Answer 33

Erosion that is directly downwards and occurs in the upper course. The river is attempting to cut vertically down to its base level.

Question 34

Hjulstrom Curve

Answer 34

A curve which shows the relationship between the size of a particle and the energy needed to pick it up, transport it, erode it or deposit it

Question 35

Entrainment Velocity

Answer 35

The velocity of the water needed to pick up a particle of a certain size. Boulders require a large velocity as do the smallest clays. Sand requires the lowest velocity.

Question 36

Graded Profile

Answer 36

The idealised long profile which a river is trying to attain. It is a concave shape.

Question 37

Wetted Perimeter

Answer 37

The amount of water that is in contact with the bed and banks of a river.

Question 38

Hydraulic Radius

Answer 38

A measure of the efficiency of a river

Question 39

Laminar Flow

Answer 39

Horizontal flow that would travel over sediment without disturbing it

Question 40

Turbulent Flow

Answer 40

Consists of erratic eddies in a vertical and horizontal direction

Question 41

Eddies

Answer 41

Currents moving in the opposite direction to river flow.

Question 42

Cuspate Deltas

Answer 42

Deltas shaped like a tooth formed by gentle, opposing currents

Question 43

Arcuate Deltas

Answer 43

Curving shoreline. Most common shape.

Question 44

Birds foot Deltas

Answer 44

Shaped like a birds food. Spread out over a wide area with many distributaries extending out into the sea.

Question 45

Hard Engineering

Answer 45

Controlling a river by using man-made structures

Question 46

Straightening the Channel

Answer 46

Shortening the river course by removing meanders to move floodwater away quicker.

Question 47

Building Levees

Answer 47

Reduces flood risk by raising the level of the river banks. Causes problems downstream

Question 48

Concrete Spillways

Answer 48

Constructed to redirect excess water upstream via an alternate route to reenter the river futher downstream

Question 49

Dams

Answer 49

Control water flowing in a river

Question 50

Soft Engineering

Answer 50

Controlling a river without building or using man-made structures

Question 51

Forecasts

Answer 51

Using weather forecasts and flood prediction software to predict floods

Question 52

Land Use Management - Zoning

Answer 52

Allowing areas of floodpain to flood naturally

Question 53

Land Use Management - Contour Ploughing

Answer 53

Reducing surface run off by ploughing fields with the contours.

Question 54

Land Use Management - Afforestation

Answer 54

Planting new trees to increase interceptions and evapotranspiration

Question 55

Wetland and Riverbank Conservation

Answer 55

Protecting existing river channels and their valleys so habitat and species diversity is maintained

Question 56

River Resoration

Answer 56

Returns the rivers to their state before managing.