Option A - Water scarcity and water quality

Question 1

What does the level of water scarcity depend on in a country?

Answer 1

• water availability
• precipitation
• population growth
• demand for water
• affordability of supplies and infrastructure

Question 2

What is ‘physical water scarcity’?

Answer 2

where water consumption exceeds 60% of the usable supply

Question 3

What is ‘economic water scarcity’?

Answer 3

where a country physically has sufficient water to meet its needs but requires additional storage and transport facilities

Question 4

What is a drought?

Answer 4

an extended period of dry weather leading to conditions of extreme dryness

Question 5

Impacts of drought

Answer 5

• reduced crop yields
• increased animal mortality
• increase illnesses in humans
• increase in forest fires

Question 6

What does water quantity depend on?

Answer 6

• rates of rainfall
• evaporation
• the use of water by plants
• river and groundwater flows

Question 7

When does ‘water stress’ occur?

Answer 7

when per capita water supply is less than 1,700 cubic metres per year

Question 8

What are the factors that affect access to safe drinking water?

Answer 8

• water availability
• water infrastructure
• cost of water

Question 9

What is eutrophication?

Answer 9

Increased amounts of nitrogen and/or phosphorus that are carried in streams, lakes and groundwater, causing nutrient enrichment.
This leads to an increase in algal blooms as plants respond to increased nutrient availability.
However, the increase in algae and plankton shade the water below, cutting off the light supply for submerged plants.
The prolific growth of algae, especially in the autumn as a result of increased levels of nutrients in the water and higher temperature → results in anoxia (oxygen starvation in the water).
On a larger scale, they may lead to the formation of “dead zones” in coastal areas close to river mouths

Question 10

How to deal with eutrophication?

Answer 10

• alter the human activities that produce pollution
• regulate and reduce pollutants at the point of emission
• restore water quality

Question 11

Consequences of irrigation

Answer 11

systems that could pump groundwater out of aquifers faster than it was recharged
increased salinity: the salinity of the remaining water increases when water evaporates
large reservoir

Question 12

What are some sources of human activities that could put pressure on water sources?

Answer 12

• agriculture
• industry
• population growth
• urbanisation
• industrialisation