Human land use affecting

Aspect
drainage basin

Outputs Source

Relief Mouth

Geology Tributary

Vegetation Confluence

1a
urbanisation, agriculture, water the compass direction that a
resources/energy slope faces

The beginning of a river (usually When water leaves a system.

in mountainous regions). (evaporation)

The end of a river (usually where the way the land changes in
it enters a sea or lake). height (steep, flat, gentle)

rocks and the structure of the

A small river that flows into a
earth (permeable, porous,
bigger river.
saturated etc)

all the plants and trees in an area

Where two rivers join or meet. (interception, evaporation,
decrease flooding etc)

1b
 Estuary River Bank

Drainage Basin Wetted Perimeter

Watershed Channel

River Long Profile Thalweg

River Bed Erosion

2a
 A tidal section near the mouth of
The (two) sides of a river channel.
a river.

The length of the bed and banks The area of land that is drained
in contact with water. by a river and its tributaries.

The route course (between bed

The dividing line between two
and banks) that a river flows
drainage basins.
through.

The course that the river takes

The fastest route of flow.
from its source to mouth.

The wearing away of material due

The bottom of the river channel.
to river action.

2b
 Abrasion (Corrasion) Upper course channel features

Corrosion (Solution) Upper course physical features

Hydraulic Action Upper course load

Attrition Middles course channel features

Why is there more vertical

erosion near the source and
Middle course physical features
horizontal erosion near the
mouth?

3a
 The process of a river's load
crashing into the bank or bed
and breaking apart.
narrow, shallow, fast, turbulent, vertical erosion

The dissolving of river load by

weak acids in the river.
Steep-sided V-shaped valleys, interlocking
spurs, rapids, potholes, waterfalls and gorges

Water and air entering cracks of

traction, angular/large boulders,
the river or material and causing
high bedload
erosion at increased pressures.

Load crashing into each other

and breaking apart.
wider, deeper, slower, lateral erosion

The load is larger near the source, so it is

less likely to be suspended in the water.
The load will bounce along the bed,
causing vertical erosion.
The load is smaller near the mouth, so it
Wider more gentle valleys, meanders, oxbow is suspended in the flow. It will crash into
lakes, floodplains the banks, causing horizontal erosion.
3b
 Middle course load Transportation

Lower course channel features Traction

Lower course physical features Saltation

Lower course load Suspension

How does the gradient affect a

Solution
river?

4a
When material is moved along a saltation, smoother/smaller, little
river with its excess energy. bedload

Large load roll along the river bed. wide, deep, slow, lateral erosion

Medium-size load bounce along the river

bed (with some suspension). Wide flat-bottomed valleys, floodplains, estuary,
levees and deltas

suspension/solution,
smooth/small, low/no bedload
Smaller load is carried in a river's flow.

steeper gradient, faster velocity,

vertical erosion, turbulent waters
The dissolving of load and carried in
solution.

4b
 Load Discharge

Why does an increase in

Deposition discharge increase
erosion/transport?

Bradshaw Model Peak discharge

Bradshaw Model Rising Limb

Velocity Falling Limb

5a
 Volume of water passing a
certain point (cm3/s OR cumecs). Material that is transported by a
Discharge = cross-section river.
(widthxdepth) × velocity

-River flows faster/with more

force/energy/pressure; The releasing and dropping
-More erosion is likely to occur/more materials down of load by gravity when the
worn away;
-More transportation/load moved river no longer has enough
-types of erosion/transport energy to transport. (smaller can
-Larger materials can be moved;
-Greater wetted perimeter
travel further)

The greatest volume of water A model showing how river

that flows in the river at a given characteristics vary from source
time. to mouth.

The increase in river discharge as rainwater flows

into the river

Speed and direction of an object

(m/s).
The decrease in river discharge as the river
returns to its normal level
5b
 Lag time Closed System

Cross-Section Inputs

Gradient Transfers

Hydrological Cycle Stores

Open System Precipitation

6a
Water cannot be added or lost.
E.g. Hydrological cycle
Time between peak rainfall and peak
discharge

When water is added into a The area of a river section at a

system. (precipitation) certain point.

When water moves within a

system. (percolation, through-
The steepness of the river bed.
flow, groundwater flow, surface
run off, infiltration)

Continuous movement of water

When water is stationary within a
through the land, oceans and
system. (lake, interception, soil)
atmosphere.

Any moisture that falls from the Water can be added or lost.
sky. E.g. Drainage basin

6b
 Infiltration Groundwater Flow

Surface Run-off Through Flow

What can increase overland flow? Interception

What can decrease overland

Evapotranspiration
flow?

Percolation Saturated Soil

7a
 When water travels from above
the ground to beneath the
ground.
(permeability/saturation/porous
The movement of water through saturated
ground.
dependent)

The movement of water through unsaturated When water travels across the ground
ground. surface.

Long period of intense rainfall,

vegetation that intercepts water
urbanisation, impermeable rock,
flow.
saturated soil

Vegetation, interception,
Water evaporated from plants in infiltration, permeable rock,
transpiration unsaturated soil, drainage
systems

Soil that cannot hold more water.

When water travels from unsaturated ground to
saturated ground.
7b
Unsaturated Soil Porous

Water Table Non-Porous

Condensation Aquifer

Permeable Dam

Impermeable Waterfall

8a
 Soil that still has space between
An object that can hold water.
its pores to hold water.

The level below which the

An object that cannot hold water.
ground is saturated with water.

A body of rock or sediment that

Water vapour cools and
stores groundwater and allows
condenses to form a cloud
the flow of groundwater.

A surface that will allow water to

A barrier placed across a river.
pass through.

A surface that will not allow

Where water descends vertically.
water to pass through.

8b
Exam mark scheme- formation of
Formation of a pothole
a waterfall

Formation of a waterfall V-shaped Valley

Gorge Interlocking Spur

Rapid Delta

Pothole Formation of a delta

9a
 Hard rock & soft rock layers;
Hard rock is resistant to erosion/soft rock is less resistant
to erosion;
Soft rock below is undercut/hard rock forms an
overhang;
Collapse of hard rock/overhang falls/hard rock falls;
- turbulent water Moves back/retreats/forms a gorge;
- rocks swept round and down (vertical eddies) Max 1 for processes hydraulic action/abrasion/solution;
- abrasion

1. waterfalls form over area of hard rock followed by area of soft rock
2. softer rock eroded by hydraulic action and abrasion more than hard
rock, creates a step in the river

Valley, upper course, vertical 3. water going over step erodes even more soft rock
4. a steep drop - the waterfall - is created

erosion
5. hard rock undercut by erosion becomes unsupported and collapses
6. collapsed rock swirled around at foot of waterfall erodes soft rock
by abrasion, creating a deep plunge pool
7. more undercutting causes more collapse, waterfall retreats leaving a
steep-sided gorge

Valleys interlocking such that the steep valley formed from

river is forced to meander. waterfall retreat

Formed when a river's velocity

Sections of rough and white
decreases as it nears the sea,
(turbulent) water when layers of
causing more deposition than
hard rock and soft rock alternate.
erosion.

-large amounts of sediment brought downstream;

-deposition in lower course;
-as speed of flow is reduced ;
-and flocculation occurs due to salt in water;
-deposited silt blocks course of river;
-which splits into distributaries to reach sea ; Holes found in the river bed.
-deposited materials are not washed away/grows
towards sea;
-due to lack of current;
-colonisation of vegetation
9b
 Distributary Braided River

Flocculation Levee

Arcuate Delta Formation of a leeve

Bird's Foot Delta Meander

Cuspate Delta Sinuous

10a
 a river that breaks off from main
river in a delta (deposition blocks
channel etc)
Rivers with variable flow erode or deposit at different
sections, creating interweaving ribbon channels.

The process of particles joining

deposited sediment that builds together, increasing the
up/a wall of earth built to prevent likelihood of deposition.
a river from flooding its banks E.g. Can be caused by salt in
areas of sea to form a delta.

-flood A regular-shaped delta, smooth and round.

-coarse sediment deposited on bank
-continuous flooding builds up sediment E.g. River Nile delta

A bend in the river caused by the thalweg Similar to the shape of a bird's foot with thin areas jutting out.
moving to the outside of the river. E.g. Mississippi delta

Shaped by opposing currents of equal force to create a smooth delta

When a river is considered to be very with a section jutting out.
bendy. E.g. Ebro delta

10b
 Oxbow Lake Floodplain

Formation of an oxbow lake Alluvium

Slip-off Slope Bankfull Discharge

River Cliff Causes of a flood

Why does a river continue to

Development of floodplain
flood after rain?

11a
 The cut-off section of a river when two
Areas that a river flood will cover. meanders join.

-faster flow of water on outside of bend;

thalweg
-erosion on outer bank; lateral
-neck narrows;
-cuts through neck during flooding/cutting
through/meander cut off;
Mineral-rich load that keeps floodplain farmland -ends/former meander sealed by
fertile.
deposition;

When the river is full and cannot

contain any more water. This
leads to flooding.
A gentle-sloping, beach-like area formed in areas
where deposition is greatest (inside of meander).

-Heavy rainfall
-Rainfall over a long period of time
-Saturation of ground/porous
-Overland flow
-Rapid run off/short lag time (steep slope)
-Rapid increase in river discharge
-Deforestation (less interception)
-Lack of flood management
-Impermeable ground
-Urban development in river catchment/on flood plain (drains go into
river/tarmac not permable) A steep-sided bank formed in areas where
-Snow melt
-Build up of waste in the river (displace water) erosion is greatest (outside of meander).

-Most of the rain does not fall on the channel;

-Takes time for overland flow to reach river; (lag)
- velocity decreases
-Water has to travel downstream; - deposited sediment (flat land)
-Much of the water gets to the river slowly - alluvium build up
through
soil/rocks/percolation/groundwater/throughflow; - fertile

11b
 Examples of Temporary
Hard Engineering
Engineering

Examples of Hard Engineering Flash Flood

Dams Topography

Soft Engineering Reservoir

Examples of Soft Engineering Locks

12a
 Building of physical structures
Sandbags (usually out of concrete or metal)
Temporary flood barriers to reduce the impacts of
flooding.

Levees
A flood that arrive with little or Flood barriers
no notice. Flood control channels
Dams

Adv
electricity
Dis adv
The shape of the land. Costly
Ugly
Can break
Flood areas

An artificial store lake that Working with nature to reduce

develops behind a dam. the impacts of flooding.

An enclosed area with gates at Reforestation / afforestation

either end that allow boats to up Controlled flooding
or down a dam. Managed retreat

12b
HEP (Hydroelectric Power) CS: flooding, Bangladesh (effects)

CS: flooding, Bangladesh

Upstream
(response)

Downstream

Why do people live on

floodplains?

CS: flooding, Bangladesh

(causes)

13a
 Effects:
43 die Renewable electricity generated
$12 damage by the force of descending water.
50,000 evacuated

Response:
6 dams, 105 reservoirs
Afforestation
Towards the river source.
Levees
Course straightening
Less development on floodplain

Towards the river mouth.

-Fertile land;
-Farmers obtain high yields of crops;
-Land is flat so easy to build on/transport/trade;
-Communications on land are easy along flood plain;
-River can sometimes be used for navigation;
-Fishing/food supply from river;
-Water supply from river;
-Scenic beauty/good view;
-Jobs in tourism;
-HEP/generate energy;
-Wash clothes/bathing;
-Religious significance/always lived there;
-Irrigation/water for crops
-Gold panning;
-Example of leisure activities etc.

Causes:
Monsoon season (70% rain)
Himalayas run-off
Urbanisation

13b