T4 (Water) Definitions

Question 1

Hydrosphere

Answer 1

All the forms in which the Earth’s water can exist

Question 2

Turnover Time

Answer 2

Time taken for water to completely replace itself in part of the system

Question 3

Aquifer

Answer 3

Underground formation of permeable rock or loose material which stores groundwater

Question 4

Precipitation

Answer 4

Conversion and transfer of moisture in the atmosphere to the land

Question 5

Interception

Answer 5

Water that is caught and stored by vegetation

Question 6

Through fall

Answer 6

Water that falls through gaps in the vegetation or drops from leaves, twigs or stems

Question 7

Stemflow

Answer 7

Water that trickles along twigs and branches and finally down the main trunk

Question 8

Evaporation

Answer 8

Conversion of solid and liquid precipitation to water vapour in the atmosphere

Question 9

Transpiration

Answer 9

Process by which water vapour escapes from living plants, mainly from the leaves, and enters the atmosphere

Question 10

EVT (Evapotranspiration)

Answer 10

Combined effects of evaporation and transpiration

Question 11

Infiltration

Answer 11

Process by which water soaks into or is absorbed by the soil

Question 12

Infiltration Capacity

Answer 12

Maximum rate at which rain can be absorbed by a soil in a given condition

Question 13

Overland flow (Surface run-off)

Answer 13

Water that flows over the land’s surface

Question 14

Condensation

Answer 14

Process by which vapour passes into a liquid form

Question 15

Sublimation

Answer 15

Conversion of a solid into a vapour with no intermediate liquid state

Question 16

Advection

Answer 16

Horizontal transfer of energy or matter

Question 17

Freezing

Answer 17

Change of liquid water into solid ice, once temp falls below 0 degrees

Question 18

Melting

Answer 18

Change from a solid ice to liquid water, when air temp rises above 0 degrees

Question 19

Steam-flow or currents

Answer 19

Movement of water in channels, such as streams and rivers

Question 20

Flooding

Answer 20

Covering of normally dry land by water

Question 21

Irrigation

Answer 21

The addition of water to areas where there is insufficient water for adequate crop growth

Question 22

Salinisation

Answer 22

(when groundwater levels close to surface) Capillary forces bring water to surface where evaporated, leaving behind soluble salts

Question 23

Physical Water Scarcity

Answer 23

Shortages as demand exceeds supply

Question 24

Water Stress

Answer 24

Demand exceeds availability by a serious amount during a certain time period or poor quality restricts its use

Question 25

Water Harvesting

Answer 25

Making use of available water before it drains away or evaporates

Question 26

Drip Irrigation

Answer 26

System of plastic tubes installed at / just below soil surface to deliver water to individual plants

Question 27

Sustainable Yield

Answer 27

The rate of increase in natural capital that can be exploited without depleting the original stock or its potential for replenishment

Question 28

Indicator Species

Answer 28

A species whose presence, absence or abundance can be used as an indicator of pollution

Question 29

Biochemical Oxygen Demand (BOD)

Answer 29

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 30

Anoxia

Answer 30

Oxygen starvation in the water

Question 31

Biotic Index

Answer 31

A biotic index indirectly measures pollution by assaying the impact on species within the community according to their tolerance, diversity and relative abundance

Question 32

Dead Zones

Answer 32

Occur when there is not enough oxygen to support marine life