Agriculture and the Environment

Question 1

What are mineral particles?

Answer 1

Rock fragments and other inorganic substances.

Question 2

What is organic content?

Answer 2

Mixture of plants, animals, and microorganisms and their dead remains.

Question 3

What makes up soil?

Answer 3

*oxygen(air)
*organic content.
*mineral particles.
*water.

Question 4

The proportion of soil components depends on:

Answer 4

*type of soil.
*how it was managed.
*local climate.
*size of particles.

Question 5

Size of sand:

Answer 5

2.0 - .02mm

Question 6

Size of silt:

Answer 6

.02 - .002mm

Question 7

Size of clay:

Answer 7

.002mm - anything smaller

Question 8

What elements do plants require in soil?

Answer 8

*nitrogen.
*phosphorous.
*potassium.

Question 9

Why are earthworms important?

Answer 9

*break down vegetation.
*mix the soil.
*aerate the soil.
*spread organic matter.

Question 10

Why is fungi important?

Answer 10

*feeds on dead matter.
*digests woody items.
*aids plants to take up nutrients.

Question 11

High levels of organic matter increase:

Answer 11

*air spaces.
*number of decomposers.
*water-holding capacity.
(prevents loss of mineral nutrients.)

Question 12

Ease of cultivation:

Answer 12

How easy soil can be ploughed.

Question 13

Types of agriculture:

Answer 13

*commercial.
*subsistence.
*arable.
*pastoral.

Question 14

Difference between commercial and subsistence farming:

Answer 14

Commercial is cultivation of food to sell for cash.
Subsistence is cultivation of food to meet the needs of the farmers.

Question 15

Difference between arable and pastoral farming:

Answer 15

Arable farming produces plants for humans.
Pastoral farming produces animals or animal related products.

Question 16

What is mixed farming?

Answer 16

Farms that grow crops for animals.

Question 17

What are yields?

Answer 17

The amount of crop harvested.

Question 18

Increasing agricultural yields:

Answer 18

*crop rotation.
*leafy crops.
*fallow.
*irrigation.
*fertilizers.
*root crops.
*legumes.

Question 19

Crop rotation:

Answer 19

Growing different crops in different plots each year.

Question 20

Fallow:

Answer 20

Land ploughed and left for a period of time to restore fertility.

Question 21

Legumes:

Answer 21

Nitrogen-fixing bacteria in root nodules.

Question 22

Leafy crops:

Answer 22

Vegetables required for their leaves.

Question 23

Root crops:

Answer 23

Deep root systems.

Question 24

Advantages of inorganic fertilizers:

Answer 24

*meets particular need.
*easy to store.
*deals with deficiency problems.
*no need to reapply.

Question 25

Disadvantages of inorganic fertilizers:

Answer 25

*cost. *leaks in heavy rain. *no immediate impact. *transport cost. *environmental impact(eutrophication etc)

Question 26

Advantages of organic fertilizer:

Answer 26

*uses natural resources. *supplies organic matter.

Question 27

Disadvantages of organic fertilizer:

Answer 27

*harder to transport. *variable in composition. *unpleasant to handle.

Question 28

Common water application methods:

Answer 28

*sprinklers. *clay pot irrigation. *trickle drip system. *flood irrigation.

Question 29

What is a pest?

Answer 29

An animal that attacks or feeds on crops.

Question 30

Pesticides:

Answer 30

Used to control pests.

Question 31

Weed control:

Answer 31

Weed-killing chemicals.

Question 32

Alternatives to herbicides:

Answer 32

*hand weeding and hoeing. *flame guns. *weed barriers.

Question 33

A crop disease is caused by?

Answer 33

Fungi, bacteria, or viruses(pathogens)

Question 34

What is selective breeding?

Answer 34

Choosing parents that exhibit desired characteristics and breeding them so the offspring has the desired characteristics.(repeated)

Question 35

Drawbacks of selective breeding:

Answer 35

Slow process and less success rate.

Question 36

GMOs:

Answer 36

Genetically Modified Organisms.

Question 37

Advantages of GMOs:

Answer 37

*disease and pest resistant. *nutritional value increases. *herbicide resistant. *longer storage life. *can be grown in inhospitable areas.

Question 38

Disadvantages of GMOs:

Answer 38

*unknown impact of the new characteristics on human health. *products are not natural. *genes might get into wild plants if interbred. *reduction in gene pool.

Question 39

Impact of agriculture:

Answer 39

*overuse of herbicides, insecticides, and fertilizers. *soil erosion. *irrigation causing salinization and water logging. *exhaustion of mineral ion content. *cash crop replace food crops. *desertification. *overproduction and waste. *loss of habitat.

Question 40

Salinization causes:

Answer 40

Salt content of soil to increase.

Question 41

Soil capping causes:

Answer 41

Soil to become hard.

Question 42

What are cash crops?

Answer 42

Crops produced for cash.

Question 43

What is desertification?

Answer 43

A process where fertile land becomes desert.

Question 44

Causes of soil erosion:

Answer 44

*overgrazing. *overcultification. *water erosion. *wind erosion. *removal of vegetation.

Question 45

Ways to manage soil erosion:

Answer 45

*terracing. *contour ploughing. *maintaining vegetation covers. *'no dig' method. *planting trees. *mixed cropping. *organic matter in soil. *intecropping. *crop rotation.

Question 46

What is terracing?

Answer 46

Rows made along a slope to prevent soil erosion.

Question 47

What is interctopping?

Answer 47

Different crops grown in between main crops.

Question 48

Eutrophication process:

Answer 48

* fertilizers are washed off land by rain. * they cause plants to grow rapidly when entering a body of water. * this prevents light from reaching the bottom and kill the plants which kill the fish. *the decomposition fish cause more oxygen loss.

Question 49

Mineral ions in fertilizers:

Answer 49

*phosphate. *potassium. *nitrate.

Question 50

Ways farmers reduce drought impacts:

Answer 50

*irrigation. *drought resistant crops. *rainwater harvesting.

Question 51

Monoculture:

Answer 51

Growing one crop in a field at a time.