Hydrosphere Flashcards
What are the different reservoirs of water in the water cycle
- oceans
- lakes
- rivers
Define the term residence time
- how long water stays in a particular reservoir
Define the term transfer rate
- how much water moves over a period of time
How do you work out residence time
residence time = volume of H2O in a reservoir/mean transfer rate
What is evaporation
- water moves from the earths surface to the atmosphere
What is precipitation
- water moves from the atmosphere to the ground,ocean,lakes
What is transpiration
- water moves from plants to the atmosphere
What is runoff
- water moves from the land to the ocean
What is interception
- water moves from the atmosphere to the plant
What is infiltration
- water moves from the surface to the soil
What is percolation
- downward movement of water through the soil
What is ground water flow
- water moving slowly through rocks towards the sea
What is transport by the wind
- water moves over the ocean to over the land
What is surface flow
- water flows downhill towards stream channels which join rivers and eventually reach the oceans
Where does the energy come from that drives the water cycle
- the sun
Define the term abstraction
- taking water from a natural reservoir for human use
What effects does urbanization have on the process and reservoir
- reduces infiltration
- increase interception
What effect does abstraction of water have on the process and reservoir
- decrease water volume underground
What effect does agriculture have on the process and reservoir
- decrease infiltration
- increase transpiration
- can increase and decrease interception
What effect does deforestation have on the process and the reservoir
- decrease transpiration
- decrease interception
- decrease infiltration
What effect does afforestation have on the process and reservoir
- increase transpiration
- increase interception
- increase infiltration
What effect does industry have on the process and the reservoir
- slows evaporation
- more water is being abstracted out of natural reservoirs
What effect does combustion have on the process and reservoir
- increase evaporation
- increase precipitation
- increase transpiration
What are the 4 types of demand for water
- population size
- affluence
- agriculture
- industry
Define the term water footprint
- the volume of water needed for the production of goods and services consumed by a country’s inhabitants
What are the uses, impacts and threats of the river nile
uses
- agriculture
- fishing
threats
- pollution
- climate change
impacts
- consequences for biodiversity
- decrease resources
What is a reservoir and why do we build them
- an artificial lake where water is stored
- to store the rain water that falls and then use it for supply’s for hotter times of the year
What are some advantages of using reservoirs
- water store
- flood risk management
- for agriculture
- healthier source of water
What are some disadvantages of using reservoirs
- displacement of wildlife
- impacts on fish migration
- changes to downstream flow patterns
What is the ideal shape of land for a reservoir
- valley with steep sides
- river already there
What is the ideal geology for a reservoir
- base rocks to be impermeable
What is the ideal catchment area for a reservoir
- large catchment area
- greater chance of creating a reservoir
What is the ideal water supply for a reservoir
- high and frequent precipitation
What is the ideal existing land use for a reservoir
- designations
What is the ideal pollution risk for a reservoir
- low pollution risk
- can see what enters the reservoir
What is the ideal sedimentation for a reservoir
- sedimentation is low
- low rate of soil erosion
What is the ideal infrastructure for a reservoir
- roads, power and water supply’s etc already there
- if roads are already there, then it is cheaper
What is an estuarine barrage
- a dam built across the mouth of a river
Problems with building an estuarine barrage
- expensive
- prevents water from flowing to the ocean
- creates obstacles for transport systems
Define the term aquifer
- a body of permeable rock which can contain or transmit groundwater
What are the 3 main features that allow the formation of an aquifer
- porosity
- permeability
- suitable geological structures
What is a confined aquifer
- aquifer below the land surface that is saturated with water
What is an unconfined aquifer
- where the rock is directly open at the surface of the ground and groundwater is directly recharged
What is an artesian well
- water well that doesn’t require a pump to bring water to the surface
What is the explanation of the consequence reduced supplies
- limited supplies for agriculture, industry and domestic use
- less food production
- migration of people
What is the explanation of the consequence subsidence
- sinking off the ground
- makes things tilted and fractured
What is the explanation of the consequence changes in surface hydrology
- disappearance of surface water features e.g lakes
- aquifer overused
- water table drops
What is the explanation of the consequence ecological impacts
- loss of freshwater habitats
- local extinction of some species
- migration of species
What is the explanation of the consequence saltwater incursion
- we can’t drink the water or use it for agriculture
- saltwater pollution - long residence time, so salt is harder to get out of the aquifer
How can we monitor aquifer water levels and rates of depletion
- boreholes - physically monitor the water table
- NASA - GRACE satellites - measures gravity levels
what is the most important aquifer in the UK
- London basin
Define the term aquifer recharge
- refilling of the aquifer
How has the north china plain been overabstracted
- aquifer is unbalanced
- due to declining groundwater levels, it can lead to drying up of streams
How has malta overabstracted their aquifer
- little lakes and rivers
- many tunnels connecting to aquifer
- water is being extracted quicker than its being replenished
Explain how rainwater is harvested and used in modern/eco buildings
- it can be collected from roofs of homes etc
- installing gutters on roofs
- sand filters are used to remove harmful particulates
Explore new ways of exploiting water
- desalination
- sewage treatment
- recycling water
How are aquifers recharged artificially
- take water from surplus places and move it to a place where it can infiltrate into the ground and recharge an aquifer
Define the term inter basin transfer
- moving water from a surplus area to a depleting area
How can we reduce domestic, industrial and agricultural water consumption
- a water metre
- drip irrigation
Impacts of turbidity
- blocks out light for photosynthesising organisms
- aesthetics - doesn’t look good
Why do we test for ph
- metals more readily go into solutions in acidic conditions
Impact of calcium content
- calcium may precipitate out and build up on pipes and appliances
Impact of pesticide concentration
- increase of it, leads to harm to non-interested pests
- organisms will become predated upon
Impacts of heavy metal concentration
- toxic to many organisms
- they can affect nervous system
Impacts of dissolved oxygen
- aquatic organisms require dissolved oxygen
- supports bacteria that can help breakdown organic matter
Impacts of chlorine retention
- kills pathogens in water
Impacts of E.coli
- it makes humans sick
What are screens and what are they used for
- water is passed through metal grids
- removes large items such as fish and plastic
What is sedimentation and what is it used for
- water is stored in sedimentation tanks
- allows for any suspended particles to settle out
What is aeration and what is it used for
- encourage aerobic bacteria
- they break down the organic matter
What is flocculation/coagulation and clarification and what is it used for
- some of the suspended particles don’t settle out
- it removes the electrostatic charge of clay particles which cause them to stick together - they flock
What is filtration and what is it used for
- allow water to perculate through sand
- removes bacteria and remaining particles
What are activated carbon filters and what are they used for
- chemicals are attracted to the carbon
- this removes pesticides
What is sterilisation and what is it used for
- add chlorine
- bubble ozone through the water
- removes pathogens
What is ph control and what is it used for
- alkaline - add an acid
- acidic - add limestone
- maintains water
What is fluoridation
- add fluoride to water
- this improves dental health
What is ion exchange and what is it used for
- metals adsorb to the ion exchange resins
- removes metals
Describe the process of reverse osmosis
- use a semi-permeable membrane
- water molecules can pass through but sand can’t
- salty water is put back into the sea
Describe the process of distillation
- get the saltwater
- allow for evaporation
- collect the condensed water
- salt is left behind in original container
