chapter 4.2

Question 1

3 Examples of where freshwater is used by humans

Answer 1

Domestic Task
Industries
Agriculture
Power Generation
Transportation
Recreation
Marking the boundaries between nations

Question 2

Define Water Security

Answer 2

Water security is a access to sufficient quantity of clean water to live sustainably.

Question 3

Define Physical and Economic Water Scarcity

Answer 3

Physical : where water consumption exceeds 60% of the usable supply.
Economic : where a country physically has sufficient water to meet its needs but requires additonal storage and transport facilities.

Question 4

List and Explain any 3 factors that impact water availablility and water scarcity.

Answer 4

Climate Change : the more the climate change, the more unusual the hydrological cycle becomes, affecting the allocation of water.
Deforestration : deforestration will lead to the destruction of water stores thus affecting the flow of water.
Contamination of rivers : if rivers are contaminated with other substances then that water will not be usable without filteration.
Mismanage of water supplies : if water allocation is done inefficiently it will lead to surplus for some and shortage for others.
Pollution : pollution of gases or water affects the quality of water.

Question 5

List 3 factors that affect water availability and water scarcity

Answer 5

Lack of knowledge and skills
Lack of finances
Lack of political will to make water a priority
Poor infrastructure and inadequate management of water services.

For understanding :
Between Urban and rural areas : people living in urban areas are more likely to be connected to piped water.
Between the rich and poor : The rich are more likely to have better access to reliable water supply.
Between Social Groups : some groups within society may be marginalized.

Question 6

Explain sustainability of freshwater usage

Answer 6

• Climate change is causing water access issues. It disrupts rainfall patterns, exaggerating the inequality of supplies. Rising temperature reduces the flow of rivers and deforestration reduces transpiration which reduces precipitation resulting in drought.

Question 7

List the large scale solutions for water scarcity.

Answer 7

Building Dams
Desalination Plants
Rainwater Harvesting on a large scale
Artificial Recharge of Aquifiers

Question 8

List the domestic solutions for water scarcity.

Answer 8

Grey water recycling
Rainwater Harvesting
Drought resistant crops
Drip irrigation
Water at night/evenings when evaporation rates are lower.

Question 9

Define Irrigation

Answer 9

Irrigation is the practice of artificially watering plants to help them grow

Question 10

Define Drought Resistance for a crop

Answer 10

Drought resistance refers to the ability of a crop to produce a satisfactory yield in conditions of water shortage

Question 11

Define desalination and its types.

Answer 11

Desalination is the removal of salts from seawater.

Type 1 - Distillation : Evaporate water, leaving the salts behind.
Type 2 - Reverse Osmosis : Using high pressure to remove salts

Question 12

List 2 Adv and 2 Disadv of rainwater harvesting.

Answer 12

Advantages (pick 2) :
Supplies clean water and decreases demand
Reduces the need to import water
Doubles as a conservation method
Improves groundwater stores
Reduces surface runoff

Disadvantages (pick 2) :
Rainfall isn’t predictable
Many people don’t have access to such technology
System needs regular maintainance
Limit to the amt of water stored
Poor installation leads to mosquitoes.

Question 13

Define aquifers and explain artificial recharge of aquifers

Answer 13

An aquifer is a layer of rock or sediment that contains water and allows it to flow

Artificial Recharge of Aquifer : a way to store water underground in times of water surplus to meet demand in times of shortage.