Life On Earth- Agriculture And Indicators Flashcards Preview

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Flashcards in Life On Earth- Agriculture And Indicators Deck (30):
0

Name 5 advances in agriculture

•monoculture
•increased use of fertilisers
•increased field size
•use of GM crops
•advancement in machinery

1

What is monoculture?

Monoculture is growing a single crop or plant species over a wide area for a large number of years

2

What are 2 advantages of monoculture?

It simplifies what machinery can be used
It reduces labour costs

3

What is a disadvantage of monoculture?

It decreases the biodiversity of an area

4

Give 3 features of intensive farming

•growing high crop yield in monocultures
•lots of chemical fertilisers
•animals are close together

5

What are the two categories of fertiliser?

Organic and chemical

6

What substances to fertilisers contain?

Nitrogen
Phosphorus
Potassium

NPK!

7

What problem environmentally can fertilisers cause?

Algal bloom

8

When fertilisers are washed into streams etc what is this called?

Leaching

9

The rapid growth of algae and them thriving in conditions is called ...,,

Eutrophication

10

What does nitrogen help?

Leaf growth

11

What does phosphorus help?

Root growth

12

What does potassium help?

Fruit and flower growth

13

Name a chemical pesticide

DDT

14

Name an organic pesticide

Biological control

15

What is biological control

Farmers introduce natural predators of the pest to control pest numbers

16

What is bioaccumulation?

The build up of pesticide in top predators

17

What is an indicator species?

The presence or absence of a species that can indicate the conditions of an environment

18

What do mayfly and stonefly nymphs indicate?

Clean water

19

What do freshwater shrimp and caddis fly larva indicate?

Partly polluted water

20

What do the bloodworm and waterlouse indicate?

Badly polluted water

21

What do the sludgeworm and rat-tailed maggot indicate?

Very badly polluted water

22

What do lichen on trees indicate?

Sulphur dioxide levels

23

What lichen indicates zero or very low so2?

Hairy

24

What lichen indicates low so2?

Shrubby

25

What lichen indicates medium so2?

Leafy

26

What lichen indicates high so2?

Crusty

27

What are GM crops?

They are plants which have had their DNA modified to give the plant a new trait

28

Name a benefit of GM crops

They could help feed developing countries

29

Name a disadvantage of GM crops

They may have unpredictable health risks