Sub 12: Intensive Food Production

Question 1

what is a monoculture?

Answer 1

when a single crop such as wheat or corn is grown over a large area

Question 2

what factors affect crop yield?

Answer 2

climate, variety, soil fertility, weeds, ergonomic practice, pests and diseases

Question 3

what are the benefits of a monoculture?

Answer 3

less competition between plants for nutrients, sunlight, space
high yield
increased productivity of land
large profit

Question 4

what are impacts of a monoculture on environment?

Answer 4

loss of species diversity
poorer soil conditions
eutrophication
biodegradable organic pollution
toxic pollution

Question 5

what is pollution?

Answer 5

the negative effect of a harmful substance on the natural environment

Question 6

inorganic pollution from intensive farming leaching of run-off nitrate or phosphate fertiliser leads to?

Answer 6

Eutrophication

Question 7

what is eutrophication?

Answer 7

increasing in the inorganic nutrient concentration of an aquatic habitat leading to a rapid population increase in single celled producers. algal bloom. increase algal productivity develops thick blanket that covers surface of water depriving lower layers of light

Question 8

what happens as a result of eutrophication?

Answer 8

death of plants, death of algae, death of animals

Question 9

biodegradable organic pollution from intensive farming and spills of animal manure causes?

Answer 9

oxygen depletion

Question 10

what is oxygen depletion?

Answer 10

biodegradable organic pollution provides food for bacteria and fungi. quantity of oxygen required for aerobic microbes to decompose organic matter in sample results in oxygen depletion. this kills species

Question 11

results of oxygen depletion?

Answer 11

death of animals, eutrophication

Question 12

what is the BOD test?

Answer 12

the biochemical oxygen demand test measures the amount of dissolved oxygen in water

Question 13

what does a high BOD indicate?

Answer 13

a high level of organic pollution in the water

Question 14

what does a low BOD indicate?

Answer 14

a low level of organic pollution in the water

Question 15

why are water samples incubated at 20°C?

Answer 15

this is the optimum temperature for bacteria to breakdown organic matter

Question 16

how is the oxygen dissolved measured?

Answer 16

using an oxygen electrode

Question 17

why is hot water a pollutant?

Answer 17

can increase the temperature of fresh water, this can increase the decomposition of biodegradable organic waste reducing the waters capacity to dissolve oxygen

Question 18

what is an indicator species?

Answer 18

by presence or absence the state of the ecosystem can be determined

Question 19

what are traditional methods of pest control?

Answer 19

crop rotation
ploughing
pesticides
insecticide
fungicide
herbicide