6.5

Question 1

exhaustion

Answer 1

removing so much of a substance from nature that it starts to run out.

Question 2

greenhouse gas

Answer 2

a gas in the atmosphere that stops heat radiating away from the Earth.

Question 3

soil pollution

Answer 3

pollution of the soil by toxic substances.

Question 4

environmental problem

Answer 4

how the environment is affected by humans.

Question 5

sea level rises

Answer 5

rises in the average level of the seawater.

Question 6

salinification

Answer 6

salt water mixing with fresh river water, groundwater and ditch water.

Question 7

fossil fuels

Answer 7

fuels that were created millions of years ago from the remains of dead plants and animals.

Question 8

pollution

Answer 8

adding substances to the environment that are harmful to it.

Question 9

enhanced greenhouse effect

Answer 9

warming of the Earth because more greenhouse gases are being emitted into the atmosphere, so that more radiated heat is reflected back to the Earth.

Question 10

chemical crop protection agent

Answer 10

toxin that is used to protect crops against pests.

Question 11

blue-green algae

Answer 11

bacteria that produce substances that are toxic to humans.

Question 12

water pollution

Answer 12

pollution of water by toxic substances.

Question 13

climate change

Answer 13

changes to the average weather conditions over a long period.

Question 14

raw material

Answer 14

substance that is taken from the environment e.g to make machinery, equipment housing and clothes.

Question 15

monoculture

Answer 15

always growing the same plants every year on large plots of land.

Question 16

greenhouse effect

Answer 16

effect in which some of the heat energy radiated by the Earth is retained by the greenhouse gases in the atmosphere.

Question 17

air pollution

Answer 17

pollution of the air, mostly by smog and fine particulates.

Question 18

nitrogen

Answer 18

important mineral in fertilizer.