Human Impact On The Environment

Question 1

What is monoculture ?

Answer 1

Vast cultivated population of one type of crop plant whose members are genetically identical.

Question 2

What is an advantage of monoculture?

Answer 2

Increased level of food production.

Question 3

What is a disadvantage of monoculture ?

Answer 3

Dependant on the use of chemicals

Question 4

What is intensive farming?

Answer 4

Producing high yield crops and ‘battery-farming’ animals indoors

Question 5

What is an advantage of intensive farming?

Answer 5

Enables farmers to increase fool yield per hectare and rear more animals

Question 6

What is a disadvantage of intensive farming?

Answer 6

Requires use of chemicals and restricts animals to cramped conditions causing stress

Question 7

Give one of the types of chemicals had in monoculture ?

Answer 7

Fertilisers

Question 8

What are the 3 essential elements for plant growth?

Answer 8

Nitrogen
Phosphorus
Potassium
(NPK)

Question 9

What does nitrogen encourage ?

Answer 9

Leafy growth

Question 10

What does phosphorus encourage ?

Answer 10

Root development

Question 11

What does potassium encourage ?

Answer 11

Fruit and flower development

Question 12

What can excess fertilisers end up making their way into?

Answer 12

Freshwater such as rivers and lochs

Question 13

What do high levels of nitrates promote ?

Answer 13

The growth of algae, leading to algal bloom

Question 14

What does algal bloom spread over ?

Answer 14

The surface of water

Question 15

What does algal bloom prevent?

Answer 15

Light from reaching organisms below the surface.

Question 16

Describe the effects of algal bloom?(5)

Answer 16

1. Fertilisers from fields leach into rivers/lochs.
2. Excess nitrate promotes rapid growth of algae forming an algal bloom.
3. Bacteria populations in the water will increase hugely as they use algae as a food source.
4. Bacterial respiration uses up dissolved oxygen in the water.
5. The reduction in the water’s oxygen causes many species to die (decreasing biodiversity)

Question 17

Since the human population is increasing at an incredible rate, what is a consequence of this ?

Answer 17

Humans need to produce far more food.

Question 18

What is a pesticide ?

Answer 18

Is a substance used to prevent , destroy or repeal pests

Question 19

What are the 3 different pesticides and what do they kill?

Answer 19

Insecticide - insects
Herbicides - unwanted plants (weeds)
Fungicides - fungi (mould/mildew)

Question 20

What is the major problem of using pesticides ?

Answer 20

They can accumulate along food chains and poison wildlife

Question 21

What is bioaccumulation ?

Answer 21

When animals at each level need to eat lots of the food, so the animals higher up in the food chain will build up a higher concentration of pesticides in their bodies.
The toxic molecules become more concentrated at each level of the food chain and are non-biodegradable
High concentrations accumulate in the tissues of the final consumer and can reach fatal levels

Question 22

What is an indicator species ?

Answer 22

Organisms whose presence or absence provides information on the environmental quality or pollution levels found in a specific area

Question 23

What do freshwater invertebrates differ in?

Answer 23

Their ability to tolerate the varying oxygen levels found in a river polluted with organic waste

Question 24

What 2 species can be found in clean water ?

Answer 24

Stonefly nymph

Mayfly nymph

Question 25

What 2 species can be found in very badly polluted water ?

Answer 25

Sludge worms

Rat tailed maggots

Question 26

What is biological control?

Answer 26

A way of controlling the population of a pest species by introducing a natural enemy such as a parasite or a predator

Question 27

What can biological control in some cases result in ?

Answer 27

A reduction in the use of chemical pesticides

Question 28

What are ladybirds used to control ?

Answer 28

Aphids

Question 29

What can the virus, myxomatosis kill?

Answer 29

Rabbits