IN TEST QUESTIONS Flashcards
How are gorges formed
-waterfall erodes soft rock due to the pressure and hydraulic action of the waterfall
-waterfall gradually retreats over a long period of time , leaving a gorge behind
-overtime the gorge erodes due to weathering and a narrow, steep sided valley
Physical factors of flooding
-size and shape of a rivers drainage basin influences how much precipication the river can recieve
-rain and steepness of the basin
-permeability of the soil and rock in a drainage basin
human factors that affect flooding
-climate change, certain areas will experiencec more frequent intense storms
-urbanisation often involves deforestation reducing vegetation cover and increases discharge
-to stop roads flooding humans build storm drains that collect raindwate
name flood management strategies
soft and hard engineering
name 4 soft engineering strategies
-tree planting
-floodplain zoning
-river restoration
-flood warning schemes
name advantages and disadvantages of tree planting
-its sustainable
-cheap
-afforestation is environmentally friendly
-takes time for trees to grow
-requires a lot of trees to be planted
-may already be urbanisation in the area
name advantages and disadvantages of floodplain zoning
-uses land effectively
-places high risk buildings (hospitals) away from flooding zones
-its difficult to replace well established land patterns
name advantages and disadvantages of river restoration
-sustainable
-environmentally friendly
-floodings not prevented
-can reduce farmland
-prefer hard engineering strategies
name advantages and disadvantages of flood warning schemes
-warnings are cheap and give people time to protect homes
-gives time to reinforce buildings (make them flood resistant)
-warnings dont stop flooding
-only effective if people are aware
compare hard and soft engineering
hard is often expensive and disrupts natural processes
soft is cheaper to build and works with natural processes and is sustainable
hard flood management on the river tees
-gabions
-concrete flood walls
-flood gates
-tees barrage
soft flood management on river tees
-flood plain zoning
-flood warning
-dreading
whats a long profile
the change in gradient with distance. starts steep reduces distance from source
whats a cross profile
shows slice of river at different points along the long profile
describe the rivers upper course
-beggining of river, nearest to source
-steep
-narrow
-current is fast, water has more energy and wears away rocks and soil
-
describe rivers middle course
-less steep
-more energy and water compared to upper
-wide and deep
-less friction as rivers wider
-
describe rivers lower coursw
-the end of the river
-channels deep and wide
-energy levels are low, current slows down
describe the shape of the rivers long profile
at the upper course its steep and has the slowest velocity as it goes down, the steepness decreases and velocity increases as it gets wider
traction
-large, heavy pebbles are rolled along the river bed.
-most common near the source of a river,
saltation
-pebbles are bounced along the river bed
-most commonly near the
source
suspension
-lighter sediment is suspended (carried) within the water,
-most commonly near the mouth
solution
