4. Water Flashcards
(18 cards)
What drives movement of water around the world
Gravity and solar radiation.
Main stores in hydrological cycle
Oceans, ice, groundwater, surface freshwater, atmosphere
Flows in the hydrological stores
Surface runoff, transpiration, evaporation, condensation, advection, precipitation, melting, percolation, stream flow and groundwater flow.
What is sublimation?
Transformation of ice directly to water vapour.
Advection meaning
Wind-blown movement of water vapour or condensed/frozen water droplets (clouds).
Percolation meaning
Water moving in the soil.
Where does the energy that powers the water cycle come from?
The sun
Consequences on deforestation for water flows/stores
- trees and plants slow down groundwater flow of water allowing for more infiltration/percolation instead of surface runoff
- trees increase evapotranspiration as water is drawn up from the soil and released to the air during transpiration.
- water falling on trees and accumulating on leaves also evaporates going back to the atmosphere water stores. (Increases humidity and in turn more precipitation)
Effect of urbanization on water flows/stores
- Land in urban areas is often paves increasing impermeabilization of the area.
-> forces water to flow over surface (surface runoff) may lead to places with no water infiltration -> accumulating on land - rivers overflowing often lead to riverbanks erosion.
- areas of natural vegetation and soil tend to be small and fragmented.
- large exchange of freshwater for waste-water in towns.
Water security meaning
Having access to sufficient amounts of safe/potable water.
Tools to increase drinkable water
- Construction of dams
- rainwater catchment systems
- desalination plants
- enhancement of natural wetlands
Water scarcity meaning
The limited availability of water to human societies.
Physical water scarcity
- dry climates in that region
- over-extraction of water for uses such as agriculture.
Economic water scarcity
- physical infrastructure is not in place to ensure clean safe water distribution
- rich have access clean water, they can afford their own systems to clean the water.
Water conservation techniques and strategies
Techniques
- Metering
- Rationing
- Greywater recycling
- Low-flush toilets
- Rainwater harvesting
Strategies:
- Greenhouses
- Aquaponics
- drip irrigation
- drought resistant crops
Phytoplankton
Microscopic plankton capable of photosynthesis (oceans, seas and freshwater)
Macrophytes
Aquatic plants that are visible (emergent from water, submerged or floating)
Maximum sustainable yield
