Sources & transport of pollutants

Question 1

Key aspects of transport & dispersion of pollutants? (3)

Answer 1

• fluid media
• settlement & leaching
• anthropogenic

Question 2

Types of fluid media?

Answer 2

water/air

Question 3

Types of anthropogenic forcings on transportation?

Answer 3

transport & placement

Question 4

2 key mechanisms of transport & dispersion in water & air?

Answer 4

• advection
• diffusion

Question 5

Advection?

Answer 5

gravity - movement with the water mass

Question 6

Diffusion?

Answer 6

turbulence & particle motion - spreading within the water mass

Question 7

2 key factors of transport & diffusion in water?

Answer 7

• restriction of vertical movement
• inputs without loss lead to accumulation of pollutants

Question 8

What restricts the vertical movement of pollutants in water?

Answer 8

• depth of water body
• stratification

Question 9

Which environments tend to have an accumulation of sediment?

Answer 9

• lakes & seas [sediments]

Question 10

Stratification?

Answer 10

density of water depends on temperature

Question 11

Relationship between density & buoyancy?

Answer 11

less dense = more buoyant

Question 12

When is water at its most dense/least buoyant

Answer 12

4 degrees Celsius

Question 13

Graph of stratification?

Answer 13

*

Question 14

Stratification in winter?

Answer 14

Less dense cold water over warmer, more dense water

Question 15

Stratification in spring?

Answer 15

wind mixing + low solar heating

Question 16

Stratification in summer?

Answer 16

Solar warming causes surface water to be less dense than deeper, cooler water

Question 17

Stratification in autumn?

Answer 17

wind mixing + low density, low solar heating

Question 18

Epilimnion?

Answer 18

surface layer
top-most layer in thermally stratified lake

Question 19

Hypolimnion?

Answer 19

under lake
dense bottom layer in thermally stratified lake

Question 20

Thermocline?

Answer 20

transition layer
abrupt temperature gradient
prevent mixing from epilimnion & hypolimnion

Question 21

During which season is the limited exchange of water between strata & entrapment of water/pollutants?

Answer 21

Summer

Question 22

What can the accumulation of pollutants in lakes & seas lead to?

Answer 22

Them becoming sinks for pollution

Question 23

What does dispersion in air depend on? (3)

Answer 23

• height reached in atmosphere
• particle size
• climate factors

Question 24

Size of surface layer in air?

Answer 24

0.1 km

Question 25

Size of atmospheric boundary layer?

Answer 25

1 km

Question 26

Range of particle size in the atmosphere boundary?

Answer 26

1 to 10 micrometers

Question 27

How do gases & aerosols transfer to troposphere?

Answer 27

- plumes - thermals - elevation [mountains]

Question 28

How far do gases & aerosols travel to get to troposphere?

Answer 28

10 to 16km

Question 29

Between which atmospheric layers does exchange occur at the equator?

Answer 29

Troposphere, stratosphere

Question 30

Layers of the atmosphere in ascending order?

Answer 30

Troposphere, stratosphere, mesosphere, thermosphere

Question 31

In which layer of the atmosphere is the ozone layer contained?

Answer 31

Stratosphere

Question 32

Tendency of gases in stratosphere?

Answer 32

to stay there - no "wash-out" unless degraded - strong radiation above ozone

Question 33

Is there a cross-equator exchange of air pollutants in troposphere?

Answer 33

No - constrained to hemisphere

Question 34

Dispersion in horizontal vs vertical plane? (2)

Answer 34

- less restricted in horizontal - more rapid in horizontal

Question 35

Does dispersion in horizontal layer occur with or against wind in boundary layer?

Answer 35

With [turbulent]

Question 36

Which 4 factors control turbulence?

Answer 36

- solar radiation - wind speed - cloud cover - topography

Question 37

What does turbulence impact?

Answer 37

dispersion

Question 38

2 important factors for transport & dispersion in soils?

Answer 38

- composition & structure - pollutant properties

Question 39

Examples of different soil compositions & structures?

Answer 39

wet, dry, anaerobic, aerobic, acid, alkaline, minerals, clays, humus, hydrous oxides of rock-derived metals, ionic composition

Question 40

Examples of different pollutant properties?

Answer 40

polar, non-polar, hydrophobic, hydrophilic, liquid, gas, particles, colloids

Question 41

What can soil composition/structure vary with?

Answer 41

Depth/profile

Question 42

What composition does a shallower soil tend to have?

Answer 42

More organic

Question 43

What composition does a deeper soil tend to have?

Answer 43

More mineral

Question 44

4 key considerations for pollutants in soils?

Answer 44

- adsorbed to soil? - strength of adsorption to materials? - bound within soil? - pollutant retained within/by soil? flows through?

Question 45

Why are the key considerations for pollutants in soils important?

Answer 45

If pollutant & soil are stuck together strongly/irreversibly what happens to soil will happen to pollutant

Question 46

Exposure pathway through air?

Answer 46

Inhalation

Question 47

Exposure pathway through water?

Answer 47

Consumption of water/ingestion of aquatic organisms

Question 48

Exposure pathway through soil?

Answer 48

Plant pathways - ingestion & diet

Question 49

3 different types of pesticides?

Answer 49

- insecticides - herbicides - fungicides

Question 50

2 issues with managing pesticides?

Answer 50

- >10,000 formulations of >450 compounds - global distribution, ubiquitous

Question 51

Indoor exposure pathways?

Answer 51

- fabric of building - importing substances - activities

Question 52

Example of fabric as exposure pathway?

Answer 52

asbestos

Question 53

Example of activities as exposure pathway?

Answer 53

hat-makers, office workers

Question 54

Example of importing substances as exposure pathway?

Answer 54

lead workers