Rivers- 6 marker Qs Flashcards
two effects of sea level change on the development of fluvial landforms
submergent landforms- i.e Rias (bristol channel) and estuaries (lower severn estuary)
emergent landforms- river terraces, flood plains and incised meanders.
two environmental impacts of flooding
water contamination by sewage that’s been deposited in the river - when it floods toxic waste flows out onto flood plains killing veg n animals and (people’s homes)
water logging of soils- flood plain gets saturated so not only soil’s capacity is full water also lays above ground. hard to reverse because vegetation and life within the water is destroyed. soil will find it hard to regain it’s integrity.
two natural processes shaping valleys
v-shaped valleys are erosional landforms. weathering and mass movements occur on the slides whilst the river erodes the base of the slopes by corrosion- rock load of river helps aid erosion of the banks and hydraulic action in the vertical direction.
two ways by which river transports sediments
by suspension- small particles (silts and clay) are suspended in the water and carried by the current
by solution- in areas of calcareous rocks- materials are dissolved in the water and carried this way
(traction- rolling)
(saltation-bouncing)
two ways by which river transports sediments
by suspension- small particles (silts and clay) are suspended in the water and carried by the current
by solution- in areas of calcareous rocks- materials are dissolved in the water and carried this way
(traction- rolling)
(saltation-bouncing)
two ways in which river basins are managed to resolve possible land-use conflicts
land use zoning
planning polices
restricting activities to different times of day.
how two human factors can influence flooding
removal of woodland…….
urbanisation……..
outline two conflicts that can arise from having different land uses in river basins
(severn)- one activity impacts on another e.g wildlife disturbed by motor boats
two activities use the same resource- e.g same water used for irrigation of agriculture and supply for human consumption.
two slope processes typical of river environments
weathering including freeze thaw
mass movements including slumping, slides
wind and hydrological processes including surface run-off, percolation, throughflow
why deposition takes place
loss of carrying capacity - loss of energy due to river meeting the sea, flatter areas, wider channel or drier climate. or an increase in load- wetter climate dumping more material into the river or waste disposal.
two reasons why economic development in river basins needs management
urbanisation
flooding risk
increased planting of forestry upstream in the welsh mountains.
ownership- who is responsible , how far do their rights extend in the river basins
who pays vs who gains- should tax payers subsidise developments that benefit a small grouo- e.g. farmers
show how slope processes influence the formation of fluvial landforms
wash processes result when soil’d infiltration of rainfall is exceeded can produce gullies and rills. gullying- a channel with steep slopes
rilling- formation of small channels -only a few cm wide and deep
