River Environments

Question 1

Slope movements - slow

Answer 1

Soil creep

Rain splash erosion

Question 2

Slope movements - flow

Answer 2

Surface Wash
Sheetwash
Throughflow

Question 3

Slope movements - fast mass

Answer 3

Slides
Falls
Slumps

Question 4

Weathering - x 2

Answer 4

Mechanical weathering - no change in state, just disintegrates. Usually occurs as the result of pressure changes in the rock

Chemical weathering - change in state, just decomposes and rots

Question 5

Mechanical weathering examples x 4

Answer 5

freeze thaw-
salt crystal growth- as crystals grow they exert pressure
exfoliation- surface layers peel off - diurnal range
Pressure release- the removal of weight - e.g. glaciers

Question 6

Chemical weathering examples x 4

Answer 6

Carbonation- the reaction between rainwater and weak carbon dioxide to create weak carbonic acid

Hydrolysis- orthoclase feldspar. the orthoclase reacts with acid water and forms kaolinite (or kaolin or china clay), silica and potassium hydroxyl. the acid and the hydroxyl are removed leaving behind china clay as the end result.

Hydration- is the process where certain minerals absorb water, and expand and change.

Oxidation- iron compounds react with oxygen to produce a reddish brown coating.

Question 7

Biological weathering

Answer 7

is the combination of mechanical and chemical impacts

Question 8

Factors affecting the type and rate of weathering: x 8

Answer 8

climate
rock type 
rock structure 
vegetation 
drainage 
aspect 
rate of erosion 
human activity

Question 9

MASS MOVEMENT-

Answer 9

it is the movement of material under the force of gravity. it tends to reduce the slope angle.

Question 10

Factors controlling type and rate of movement x10

Answer 10

climate
rock type 
rock structure
relief 
vegetation 
drainage 
aspect 
rate of erosion 
shock from something to trigger it - traffic
human activity - cuttings, making the slope steeper than their stability slope

Question 11

Erosion - the rate is determined by the energy available and the resistance if the surface

Types of erosion - x4

Answer 11

Abrasion
Hydraulic action
Attrition
Solution

Question 12

Transport - the rate is determined by the energy available and the weight of the load

Types of river transport x5

Answer 12

Floatation - on the surface 
Traction - rolling along the bed 
Saltation - bouncing along the bed 
Solution - dissolved in the water
Suspension - held in the water

Question 13

Deposition - determined by the energy loss level and the weight of the load

Answer 13

Bed load - coarse and dropped first. cobbles then pebbles, then sand
Suspension - silt and sand
Solution - rarely dropped unless mixes with salt in the estuary and delta

Question 14

River basin (catchment)

Answer 14

is the catchment area within which water is supplied by precipitation or by underground sources, and is transferred out by a stream

Question 15

Human uses of a river basin

Answer 15

1. Water supply
2. Industry
3. Residential use
4. Agriculture
5. Transport
6. Power (HEP)
7. Recreation
8. Conservation
9. Flood defence

Question 16

Conflict between land uses in a river basin (RIVER NILE and R.Exe CASE STUDY)

Answer 16

Between different land uses- Aswan Dam key factor

Within the same land use- recreation conflict