Human Influences on the Environment

Question 1

define pollution

Answer 1

the release of substances into the environment that cause harmful effects

Question 2

types of pollution

Answer 2

water
air
land

Question 3

what causes air pollution

Answer 3

CO2:
- burning fossil fuels (cars, industry, heating)
- deforestation
methane:
- rice paddies, cattle waste

Question 4

what chemicals pollute the air

Answer 4

• carbon dioxide
• carbon monoxide
• sulphur monoxide
• nitrogen oxides
• methane
• CFCs

Question 5

what are the consequences of air pollution

Answer 5

• global warming
• acid rain
• ozone hole
• smog

Question 6

explain the greenhouse effect

Answer 6

high energy, short-wave radiation from the sun reaches the earth
some energy is re-emitted as longer wave radiation
some long wave radiation is absorbed by the greenhouse gases and re-emitted back to the earth
as a consequence the earth’s surface and the lower atmosphere is warmed up

Question 7

define global warming

Answer 7

when there is an increased concentration of greenhouse gases more long wave radiation is absorbed by them and re-emitted back to the earth, increasing the overall temperature of the globe

Question 8

consequences of global warming

Answer 8

• polar ice caps would melt and sea levels rise
• change in rainfall patterns: flooding/drought
• extremes of weather e.g. hurricanes, storms, flooding
• the change in climate would affect ecosystems and threaten biodiversity

Question 9

greenhouse gases

Answer 9

carbon dioxide (CO2)
methane (CH4)
nitrous oxide (N2O)
water vapour (H20 (g))

Question 10

combustion equation

Answer 10

fossil fuel + oxygen –> carbon dioxide + water + energy

Question 11

define deforestation

Answer 11

the removal of a forest with the land into non-forest uses

Question 12

deforestation:

… photosynthesis –> less CO2 … away more CO2 in …

Answer 12

less
locked
atmosphere

Question 13

deforestation:

… of trees –> … CO2 released –> … CO2 (and less O2) in atmosphere

Answer 13

burning
more
more

Question 14

deforestation:

loss of … –> some species …

Answer 14

habitats

endangered

Question 15

deforestation:

loss of soil … –> soil washed away > leaching + …

Answer 15

anchor

erosion

Question 16

deforestation:
disturbances of water …
- less … > reduced …. > ….
- lacks of stems, litter, trunks > increased water … after rainfall > …

Answer 16

cycle
transpiration
rainfall
droughts
run off
flooding

Question 17

how much methane do cattles belch annually out of the worlds methane production and rice paddies

Answer 17

16% each!

Question 18

when is methane produced naturally

Answer 18

when organic matter is broken down by microorganisms in the absence of oxygen (rice paddies, landfill sites)

Question 19

acid rain is made up of what

Answer 19

sulphur dioxide and nitrogen oxides both from burning fossil fuels (cars, industries and heating)

Question 20

acid rain formation

Answer 20

nitrogen + oxygen –> nitrogen oxides
sulphur + oxygen –> sulphur dioxides

nitrogen oxides + water vapour–> nitric acid
sulphur dioxide + water vapour–> sulphuric acid

ALL + rain –> acid rain

Question 21

what PH is acid rain

Answer 21

4-5 unlike normal rain of around 5.3

Question 22

what does acid rain lead to

Answer 22

• death of trees
• acidification of lakes (aquatic animals killed)
• acidification of soil
• corrosion of buildings

Question 23

types of water pollution

Answer 23

inorganic fertiliser
sewage
pesticides
chemical waste

Question 24

what do inorganic fertilisers contain

Answer 24

• nitrates
• potassium
• phosphorus

Question 25

how do inorganic fertilisers reach healthy water ecosystems

Answer 25

run off (especially nitrates)

Question 26

explain what happens in eutrophication

Answer 26

1) excessive nitrates are washed into pond from runoff fertiliser
2) as nitrate levels rise, algae and aquatic plants rapidly reproduce (algal bloom)
3) the algae prevent light from penetrating through the water, so submerged plants cannot photosynthesise and die
4) the algae also die as they run out of nitrates. bacteria decay the dead plants and algae and use up more and more oxygen in respiration
5) the water may become totally anoxic (without oxygen) and all life in the water will die

Question 27

how does sewage pollute water:
Decomposers such as … and … decay the organic matter in sewage and thereby use up … as they respire
The water becomes … in the same way as in eutrophication and fish and other animals …

Answer 27

bacteria
fungi
oxygen
anoxic
die

Question 28

define sustainable development

Answer 28

improving the quality of life without compromising future generations