Topic 4 - Water, Food Production Systems and Societies

Question 1

What are the flows in the hydrological cycle?

Answer 1

Evapotranspiration, evaporation, condensation, precipitation, flooding, surface-off, infiltration

Question 2

What are the storages in the hydrological cycle?

Answer 2

Include organisms, water bodies such as oceans, aquifers, lakes, soil, rivers, atmosphere, glaciers and ice caps

Question 3

The water budget

Answer 3

A quantitative estimate of the amounts of water in storages and flows of the water cycle

Question 4

Surface currents (ocean)

Answer 4

Upper 400m of the ocean, moved by wind

Question 5

Deep water currents (ocean), also called thermohaline currents

Answer 5

Make up 90% of ocean currents and cause the ocean conveyor belt

Question 6

El Nino

Answer 6

Normal trade winds are reversed across the Pacific and water moves east rather than west. Leads to warmer water hitting South America rather than it receiving cold upwelling of water (and nutrients)

Question 7

Aquifer

Answer 7

Store of water held in porous rocks underground

Question 8

Salinisation

Answer 8

The process in which the salt concentration in soil increases

Question 9

Grey water

Answer 9

The water from showers, baths, laundry, kitchen sinks which can be used for for flushing, in gardens

Question 10

Economic water scarcity

Answer 10

Water available within your country boundaries (perhaps under ground) but you do not have the technology or money to access / clean it

Question 11

Physical water scarcity

Answer 11

A lack of water within your country (arid areas). You may be able to use tech / money to replenish through desalination, cloud seeding, importation

Question 12

Continental shelf

Answer 12

The extension of continents under the seas and oceans

Question 13

UNCLOS (UN convention on the Laws of the Sea)

Answer 13

1982, designated continental shelves belong to the country from which they extend. Also designated a 200 nautical mile (370 km) limit from the low water mark of a shore as an economic exclusive zone belonging to that country. Outside of this zone are international waters which no one country controls

Question 14

Phytoplankton

Answer 14

Single cell organisms that can photosynthesise and are the most important producer in the ocean accounting for 99% of primary productivity

Question 15

Zooplankton

Answer 15

Single cell organisms which eat phytoplankton and their waste

Question 16

Fishery

Answer 16

Exists when fish are harvested in one way or another - it might be wild fisheries / capture fisheries or aquaculture

Question 17

Aquaculture

Answer 17

The farming of aquatic organisms in both coastal and inland areas involving interventions in the rearing process to enhance production

Question 18

Tragedy of the Commons metaphor

Answer 18

If a resource is seen as belonging to all, we all tend to over-exploit it if we can. It is worth taking all the fish you can before someone else takes it. Assumes humans are selfish. Solution is to regulate resource consumption, set quotas, cooperation, set limitis

Question 19

Maximum sustainable yield

Answer 19

The highest amount of a resource that can be taken without permanently depleting the stock

Question 20

Optimal sustainable yield

Answer 20

Lower value than maximum sustainable yield (MSY) as it takes more into consideration the fact that some of your resource (i.e. fish) may have disease, m/f ratio not considered and age of fish also not considered in MSY

Question 21

Aquatic pollutants

Answer 21

Include organic material, inorganic plant nutrients (nitrates and phosphates), toxic metals, synthetic compounds, suspended solids, hot water, oil, radioactive pollution, pathogens, light, noise and biological (invasive species)

Question 22

Biochemical oxygen demand (BOD)

Answer 22

A measure of the amount of dissolved oxygen required to break down the organic material in a given volume of water through aerobic biological activity

Question 23

Biotic index

Answer 23

Indirectly measures pollution by assaying the impact on species within the community according to their tolerance, diversity and relative abundance

Question 24

Eutrophication

Answer 24

Can occur when lakes, estuaries and coastal waters receive inputs of nutrients (nitrates and phosphates) which result in an excess growth of plants and phytoplankton

Question 25

Dead zones

Answer 25

Can occur in oceans and freshwater when there is not enough oxygen to support marine life

Question 26

Water pollution

Answer 26

Is the pollution of water bodies by pollutants either directly or indirectly