Flashcards in Wetlands and flooding Deck (11)
What are wetlands?
Areas where water covers soil all year round
(1) colonise to make the soil nutrient-rich
Wetlands vary due to regional and local differences in (2), topography, (3), hydrology, (4) and human factors
1 - Hydrophytes
2 - soil
3 - climate
4 - vegetation
- (1) people live close to and depend on wetlands
- Trap (2) water and distribute it across the (3)
- Natural protection against (4)
- Supports the (5) cycle, recreational use and habitat
1 - 300-400 million
2 - flood
3 - floodplain
4 - coastal erosion and storm surges
5 - carbon
What is the Pantanel?
The largest wetland area in Central South America in the Upper Paraguay river basin
Drought increases tree (1) which reduces (2) ranching, even intended (3) can get out of control, usual January rainfall is (4)
1 - mortality
2 - cattle
4 - 210mm
What is the difference between fluvial and pluvial flooding?
F - river flooding
P - caused by excessive rainfall not as a result of a river
What is the usual cause of flooding in the UK, SE Asia, Iceland and Bangladesh? (Spacial variations)
UK - Prolonged heavy rain with low pressure systems in a progressive cycle during autumn and early winter
SE A - monsoon season July-Sept
I - Glacial 'jokulhaup'
B - Flood plain
What are the physical causes of flooding?
- Meteorological (short-term weather event) or climatic causes
- Depression sequence e.g. succession of intense storms has a cumulative effect on the drainage system causing high pressure
- Low lying land
- Melting snow or ice
What are the human causes of flooding?
- Ploughing (compacts the soil)
- Impermeable surfaces and drains
What are the socio-economic impacts of flooding?
- Deaths and homelessness
- Cars washed away
- Houses collapse
- Dangerous animals in floodwater
- Crops and livestock damaged
- Insurance more expensive
- Business disruption