Geography 4.6 - Landscapes And Processes

Question 1

What is meant by the long profile of a river?

Answer 1

Shows changes of the height of the river from source to mouth

Question 2

Compare hydraulic action with abrasion

Answer 2

The abrasion of a river is when the rocks, sand and pebbles erode the river bed. Hydraulic action occurs when the motion of water against a rock surface produces mechanical weathering

Question 3

Define weathering

Answer 3

Weathering is the breaking down or dissolving of rocks and minerals on Earths surface

Question 4

Compare freeze thaw and biological weathering

Answer 4

The formation of ice can also break rocks. If water gets into a crack in a rock and then freezes, it expands and pushes the crack further apart. When the ice melts later, water can get further into the crack. When the rock freezes again, it expands and makes the crack even bigger.

Biological weathering is the weakening and subsequent disintegration of rock by plants, animals and microbes. Growing plant roots can exert stress or pressure on rock

Question 5

Compare a flashy and subdued hydrograph

Answer 5

A ‘flashy’ hydrograph has a short lag time, high peak discharge, and steep rising and falling limbs.In a flashy hydrograph, the river is more likely to flood.

Question 6

Key features of a hydrograph

Answer 6

Lag time, rising limb, peak discharge

Question 7

How can physical factors affect hydrographs

Answer 7

Where gradients are steep, water runs off faster, reaches the river more quickly and causes a steep rising limb