Key Terms

Question 1

What is a flow/transfer

Answer 1

A form of linkage between one store/component and another that involves movement of energy or mass

Question 2

What is an input

Answer 2

The addition of matter and/or energy into a system

Question 3

What is a store/component

Answer 3

A part of the system where energy/mass is stored or transformed

Question 4

What is a system

Answer 4

A set of interrelated components working together towards some kind of process

Question 5

What are 2 examples of models?

Answer 5

• the water cycle
• the system

Question 6

What is a system?

Answer 6

An assemblage of interrelated parts, a series of stores or components that have flows or connections between them

Question 7

What are the three types of property?

Answer 7

Elements, attributes and relationships

Question 8

What are elements?

Answer 8

The things that make up the system of interest

Question 9

What are attributes?

Answer 9

The perceived characteristics of the elements

Question 10

What are relationships?

Answer 10

Descriptions of how the various elements (and their attributes) work together to carry out some kind of process

Question 11

What characteristics do most systems share?

Answer 11

• they have a structure that lies within a boundary
• they are generalisations of reality, removing incidental detail that obscures fundamental relationships
• they function by having inputs and outputs of material (energy or matter) that is processed within the components causing it to change in some way

Question 12

What is atmospheric water?

Answer 12

Water found in the atmosphere mainly water vapour with some liquid water (cloud and rain droplets) and ice crystals

Question 13

What is cryospheric water?

Answer 13

The water locked up on the earths surface as ice

Question 14

What is the hydrosphere?

Answer 14

A discontinuous layer of water at or near the earths surface, it includes all liquid and frozen surface waters, groundwater held in soil and rock and atmospheric water vapour

Question 15

What is oceanic water?

Answer 15

The water contained in the earths oceans and seas but not including such inland seas as the caspian sea

Question 16

What is terrestrial water?

Answer 16

This consists of groundwater, soil moisture, lakes, wetlands and rivers

Question 17

What are isolated systems?

Answer 17

No interactions with anything outside the system boundary
No input or output of energy or matter
Many controlled laboratory experiments are this type of system and they are rare in nature

Question 18

What are closed systems?

Answer 18

Have transfers of energy both into and beyond the system boundary but not a transfer of matter

Question 19

What are open systems?

Answer 19

Where matter and energy can be transferred from the system across the boundary into the surrounding environment
Most ecosystems are examples of open systems

Question 20

What is dynamic equilibrium?

Answer 20

When there is a balance between the inputs and the outputs

Question 21

What is positive feedback?

Answer 21

Where the effects of an action are amplified or multiplied by subsequent knock on or secondary effects

Question 22

What is negative feedback?

Answer 22

Where the effects of an action are nullified by its subsequent knock on effects

Question 23

What is bankfull?

Answer 23

The maximum discharge that a river channel is capable of carrying with out flooding

Question 24

What is base flow?

Answer 24

The normal day-to-day discharge of the river and is the consequence of slow moving soil throughflow and groundwater seeping into the river channel

Question 25

What is discharge?

Answer 25

The amount of water in a river flowing past a particular point expressed as m3s-1 (cumecs)

Question 26

What is lag time?

Answer 26

The time between peak rainfall and peak discharge

Question 27

What is peak discharge?

Answer 27

The point on a flood hydrograph when river discharge is at its greatest

Question 28

What is a storm flow?

Answer 28

Discharge resulting from storm precipitation involving both overland flow, throughflow and groundwater flow

Question 29

What is a storm hydrograph?

Answer 29

A graph of discharge of a river over the time period when the normal flow of the river is affected by a storm event

Question 30

What is potential evapotranspiration?

Answer 30

The amount of water that could be evaporated or transpired (or both) from an area if there was sufficient water avaliable

Question 31

What is precipitation?

Answer 31

Water that falls to the earth in any form
Eg rain sleet hail snow

Question 32

What is stem flow?

Answer 32

Water reaches the ground by flowing down trunks or stems or by dropping off leaves

Question 33

What is overland flow? (Surface runoff)

Answer 33

Occurs during heavy rainfall when the ground is saturated or if surfaces are impermeable, very rare except in urban area

Question 34

What is groundwater?

Answer 34

Water stored below the water table in saturated soil or rock

Question 35

What is groundwater flow?

Answer 35

Water in this zone moves laterally at a very slow rate, it transfers water through their bed and banks long after a rainfall event

Question 36

What is percolation?

Answer 36

A vertical movement of water from above the water table to below the water table, if the bedrock is impermeable eg granite, no percolation can occur

Question 37

What is infiltration?

Answer 37

The passage of water vertically into the soil infiltration cannot occur if soil is saturated

Question 38

What is a throughflow?

Answer 38

Water flows laterally through the soil to the channel, mainly along ‘pipes’ caused by animal activity or growth of plant roots

Question 39

What is transpiration?

Answer 39

Biological process where water is lost as vapour through small pores in plants leaves

Question 40

What is surface water?

Answer 40

Water stored on the surface eg lakes and rivers

Question 41

What is interception?

Answer 41

Raindrops fall on vegetation preventing it from reaching the soil and river

Question 42

What is soil water?

Answer 42

Water stored in the soil above the water table

Question 43

what is evaporation?

Answer 43

Moisture lost into the atmosphere by suns heat and wind

Question 44

What is channel fall?

Answer 44

Precipitation directly entering the river channel