The Hydrosphere

Question 1

Name 3 examples of water sources that have been unsustainably exploited

Answer 1

Colorado USA, Murray-darling Australia, yellow river china

Question 2

How does Deforestation impact the local water cycle?

Answer 2

Reduced transpiration which leads to reduced precipitation downwind

Increased infiltration or runoff

Question 3

Define transpiration

Answer 3

Loss of water from plants by evaporation of water in the stomata in leaves

Question 4

Define evapotranspiration

Answer 4

All water that evaporates, including transpiration

Question 5

Define percolation

Answer 5

The movement of water between the particles of rock/soil

Question 6

Define the term infiltration

Answer 6

The process by which surface water enters the ground between the particles of soil or rock

Question 7

Define groundwater flow

Answer 7

Movement of water through the pore spaces and fissures in permeable rock

Question 8

Name two ways in which urbanisation impacts local water cycles

Answer 8

Increased runoff
More rapid runoff
(Due to concrete/impermeable rock)

Question 9

What impacts can reservoirs have on local water sources?

Answer 9

Altered downstream flow
Reduced turbidity downstream
Sedimentation in the reservoir

Question 10

What effects do aquifers have on local water cycles?

Answer 10

Lowered water table
Loss of surface water features eg lakes and rivers
Saltwater incursions into coastal aquifers

Question 11

Describe the impacts of the building of the three gorges dam china🤓

Answer 11

Arable land lost (60,000 acres)
1.3m people displaced
Threats to pink river dolphin

Question 12

Describe one desalination case study and discuss some of the negatives of using this type of water supply

Answer 12

Ras Al-Khair Saudi Arabia or Carlsbad desal California
70 percent of Saudi Arabia’s water comes from desalination
Most expensive water supply
Produces brine which is dumped back into the ocean

Question 13

Describe one example of an estuary barrage used for water supply and discuss some of the positives of using this type of water supply

Answer 13

Avoids flooding large areas like for reservoirs
Cities close to estuaries-high demand
Combined with roads/rail links recreation and transportation

Question 14

Describe two methods used to slow down rates of evaporation in reservoirs

Answer 14

“Shade balls” used in reservoirs
Solar panels constructed over the top of reservoirs to reduce evaporation

Question 15

What is the second stage of treating potable freshwater?

Answer 15

Aeration
High levels of oxygen forced into the water which will rapidly break down bacteria on the water

Question 16

What is the third stage of potable freshwater treatment?

Answer 16

Sedimentation
Suspended solids sink to bottom and are removed
Filtration-suspended solids trapped by passing water through sand filter

Question 17

What is the fourth process used for treating potable freshwater? After screening, aeration, sedimentation

Answer 17

Clarification/flocculation-clay particles allowed to sediment, then are removed more easily

Question 18

What four steps of treating potable freshwater follow after clarification before they can be distributed out to the public?

Answer 18

Activated carbon filters
Chlorination
PH control
Fluoridation

Question 19

How does the treatment of saltwater differ from treating freshwater?

Answer 19

The water goes through filters and then undergoes reverse osmosis to eradicate the salt before going through chlorination etc

Question 20

Describe reverse osmosis

Answer 20

Saline water filtered at a very high pressure through a partially permeable membrane/small polyamide tubes. Fresh water collected at around half the volume of original. Brine is then returned to the sea

Question 21

What is fluoridation?

Answer 21

Fluorides added to the water in some areas to improve dental health of consumers

Question 22

Define percolation

Answer 22

The movement of water between the particles of soil or rock

Question 23

Define residence time

Answer 23

The average duration that a molecule remains a reservoir

Question 24

Define the term transfer rate

Answer 24

The volume of material transferred from one reservoir to another per unit time

Question 25

Define infiltration

Answer 25

The flow of water into the ground

Question 26

Define percolation

Answer 26

The movement of water between the particles of soil or rock