Chapter 11 Guided Viewing
Case Study: Biofuels and Banana Chips: Food Crops vs. Fuel Crops
1. Why do pig farmers have to feed their pigs “junk-food”?
Crops have gone up in cost, so instead, farmers buy junk food to feed their pigs because it is cheaper.
Agroecosystems
2. Explain how agroecosystems halt ecological succession.
Agroecosystems halt ecological succession is by having crops grow in early successional states (they grow fast and spread widely and rapidly).
3. What is the problem with growing “monocultures”?
Monocultures are when entire crops become vulnerable to attack by a single disease or change in environmental conditions.
4. Why does growing plants in neat rows and fields make it easier for pests?
The crop plants can't hide if they are placed in neat rows and fields.
5. How does plowing fields over and over damage the soils? Explain.
Plowing exposes soil to erosion- damages physical structure, leading to a decline in organic matter and loss of chemical elements.
6. What are the other 2 ways that agrocultures are harmful to ecosystems?
Agroculture lacks layers of soil-which can be made unsustainable from plowing.
The Plow Puzzle
7. How much of the top soil in the U.S. has been lost since European settlement?
One third of the top soil has been lost. 80 million hectares.
Can We Feed the World?
8. What percentage of the world’s land area is used for agriculture?
38%
How We Starve
9. What is the difference between undernourishment and malnourishment?
Undernourishment is when there are insufficient calories in food so the person has no energy to work. Malnourishment is when there is a lack of a specific chemical such as proteins or vitamins.
10. Why does providing food aid to countries in need actually work against increased availability of locally grown food?
The free food undercuts local farmers-making them unable to compete with it.
What We Grow on the Land
11. Most of the world’s food is produced by only 14 species. List them below in order of importance:
Wheat, rice, maize, potatoes, sweet potatoes, manioc, sugarcane, sugar beet, common beans, soybeans, barley, sorghum, coconuts, and bananas.
12. What is a forage crop?
Food grown for domestic animals.
13. Define the following:
- Rangelands: provides food for grazing and browsing animals without plowing and planting.
- Pastures: are plowed, planted and harvested to provide forage.
14. What impact does the number of livestock around the world have on rangeland and pasturelands?
More than 34 million kilometers are used for pastures worldwide-larger than size of Canada, U.S, Mexico, Brazil, Argentina, and Chile combined. Half of Earth's land area is used as a rangeland.
15. Why are feedlots considered to be a big source of local pollution?
Penned cattles are often crowded and are fed grain or forage. Manure builds up in large mounds and pollutes local streams.
16. What is a benefit of farming animals rather than crops?
Land too poor for crops, that people can eat, can be excellent rangeland with grasses and woody plants that domestic livestock can eat.
Soils
17. How does rainwater affect the soil horizon? Explain.
Rainwater is slightly acidic, when it moves down into soil, iron,calcium, magnesium, and other nutritionally important elements are leached.
18. What is soil fertility? How it is determined?
It is the capacity of a soil to supply nutrients necessary for plant growth.
19. Why are soils in humid and tropical areas considered to be poor? What happens to them after deforestation?
Soils in these areas have a poor amount of nutrients. After deforestation, it is hard for reforestation to occur.
20. What is the problem with soils in semi-arid regions?
Soils that accumulate certain clay minerals may swell and crack roads, walls, and buildings.
21. Why are coarse-grained soils more susceptible to erosion that soils that contain more clay?
Coarse-grained soils have small clay particles that retain water and retard the movement-causes the clay to erode.
22. Soil Horizons: Define each of the soil horizons
Horizon O: Upper horizon with the most organic material.
Horizon A:Upper horizon composed of both mineral and organic materials.
Horizon E: Composed of light-colored materials resulting from leaching of clay,calcium,magnesium and iron.
Horizon B: Enriched in clay, iron oxides, silica, carbonate or other material leached from overlying horizons.
Horizon C: Composed of partially altered parent material.
Horizon R: Unweathered parent material.
Restoring Our Soils
23. What is the difference between organic and inorganic (artificial) fertilizers?
Organic fertilizers are made naturally-improve both chemical and physical characteristics of soil. Artificial fertilizers are made industrially.
24. Define the following:
Macronutrient: Chemical element required by all living things in large amounts.
Micronutrient: Chemical element required in small amounts by all life forms or in moderate to small amounts for some forms of life.
Limiting Factor: A factor that is limiting and if that factor isn't improved, nothing else will make a difference.
Controlling Pests
25. In the U.S, how much of the potential harvest is lost to pests?
1/3 of potential harvest is lost to pests.
26. What is the definition of a weed?
Weeds are plants that are in places we do not want them to be.
Pesticides
27. What are the differences between inorganic and organic pesticides?
Inorganic pesticides are pesticides in forms of inorganic chemicals. Organic pesticides are made from organic compounds.
28. What are some of the reasons why pesticides are considered to be ineffective?
Pests can create a resistance and then can reproduce pests that can also have a resistance to that pesticide-that pesticide will no longer be of use.
29. Define Integrated Pest Management (IPM) AND explain HOW it works:
IPM is the idea that the goal can be control rather than complete elimination of a pest. It uses a combination of methods, including biological control, certain chemical pesticides and some methods of planting crops.
30. What is the use of biological control and give an example:
Biological control is use of one species that is a natural enemy to another. An example is BT-a disease to caterpillars.
31. What was the “green revolution”?
The "green revolution" were programs that led to development of new strains of crops with higher yields, better resistance to disease, or better ability to grow under poor conditions.
Genetically Modified Food: Biotechnology, Farming and Environment
32:. What are the 3 practices of genetic engineering?
1. Faster and more efficient ways to develop new hybrids.
2. Introduction of the terminator gene.
3. Transfer of genetic properties from widely divergent kinds of life.
33. What are the PROS and CONS of developing hybrid crops?
PROs-Can lead to hybrids that require less fertilizer, pesticide and water.
CONs-May produce superhybrids that can grow where they are not wanted and become pests.
34. What is the terminator gene and what does it do?
The terminator gene is a gene that terminates-makes seeds from a crop sterile and prevents GMOs from spreading.
35. What are the political and social concern with companies using seeds with terminator genes?
Terminator gene will allow U.S and corporations to control world food supply.
36. How are GMO (Genetically Modified Organisms) helpful?
GMOs can give food new nutrients and can give a higher crop yield than normal.
37. How can GMO’s be harmful?
GMOs can cause diseases to animals such as caterpillars and endangered species like monarch butterflies.
Aquaculture
38. What is aquaculture and how can it be helpful?
Aquaculture is farming of marine organisms-can provide food of high nutritional quality.
39. What is mariculture?
Farming of ocean fish-producing a small part of the total marine fish catch.
40. How can aquaculture and mariculture harmful to the environment?
Fishponds and marine fish release wastes polluting local environments. It can damage biodiversity.
Critical Thinking Issue: Will There Be Enough Water to Produce Food for a Growing
Population?
1: How might dietary changes in developed countries affect water availability?
If people in developed countries have diets that are more dependent on fruits and vegetables, then the demand for those items will go up. Higher demand for these foods mean more water that would need to be consumed to fit needs of people in those countries.
2. How might global warming affect estimates of the amount of water needed to grow crops in the 21st century?
If Earth's temperature increases, more droughts would occur. More droughts means more water needed for drinking and domestic use.
3. Withdrawing water from aquifers faster than the replacement rate is sometimes referred to as “mining water”. Why do you think this term is used?
The machines used in the process of withdrawing the water could be also used in mining for valuable minerals.
4. Many countries in warm areas of the world are unable to raise enough food, such as wheat, to supply their populations. Consequently, they import wheat and other grains. How is this equivalent to importing water?
The wheat and other grains grew with help of sunlight, air, and water.
5. Malthusians are those who believe that sooner or later, unless population growth is checked, there will not be enough food for the world’s people. Anti-Malthusians believe that technology will save the human race from a Malthusian fate. Analyze the issue of water supply for agriculture from both points of view.
Malthusian-populations grow, higher demand for food. This food requires water to grow-more food needed, more water needed to feed population.
Anti-populations grow, technology grows also. Better technology means better and more efficient ways to conserve water when demand is high.
Directions: Using the Soil Pyramid Program- Identify the Type of Soil with the Following Percent Compositions
- Sand: 30
Clay: 30
Silt: 40
Answer: Clay Loam
- Sand: 45
Clay: 10
Silt: 45
Answer: Loam
Directions: Determine the Type of Soils that are Characteristics of Each Specific of These Terrestrial Biomes and List Why?
Tundra: No true soils, Too cold of a layer and
Taiga (Boreal Forest): Podzolization, result of the acid soil solution produced under needleleaf trees
Temperate Broadleaf Deciduous: Brown forest soil, Hummus content of A and Horizon gives it a brown color
Mediterranean Scrub: Eroded soils because they are maintained by fires and goats.
Temperate Grassland: Dark brown, mild leaching, high organic content, and concentration of calcium carbonate in the B horizon
Scrubland: Light gray, Little hummus to give brown color
Tropical Rainforest: Oxisols, Severely leached, Rapid bacterial decay prevents hummus from building up
Tropical Savannah: laterization is the dominant soil-forming process and low fertility oxisols can be expected
Directions: Define and describe each of the alternative methods to traditional soil tillage
Windbreaks: Farmers plant trees along borders to cut down on wind erosion.
Cover Crops: Planting crops that grow during the most erosive fall and spring months. Winter crops act as a cover to protect from eroding soil.
Grassed Waterways: Farmers plant grassy strips to keep soil from running away with water.
Contour Cultivation: Farmers plant and cultivate their crops to follow contour of a field. It produces furrows that are at an angle to the field. Irregular surface makes it more difficult for water to erode soil.
Strip Cropping: Alternate a field with strips of different crops. A type of contour farming
Forages: Forage crops included in a rotation to cut down on erosion.
Conservation Tillage:Leaving stalks and leaves of harvested crops on their fields to protect soil from wind and rain.
No-Till: Farmers leave all of the last crop's residue while planting a new crop
Ridge Tillage: Forming soil into ridges and planting on ridges. Less likely to erode because the plant and soil material is not broken loose by machinery.
1. Why do pig farmers have to feed their pigs “junk-food”?
Crops have gone up in cost, so instead, farmers buy junk food to feed their pigs because it is cheaper.
Agroecosystems
2. Explain how agroecosystems halt ecological succession.
Agroecosystems halt ecological succession is by having crops grow in early successional states (they grow fast and spread widely and rapidly).
3. What is the problem with growing “monocultures”?
Monocultures are when entire crops become vulnerable to attack by a single disease or change in environmental conditions.
4. Why does growing plants in neat rows and fields make it easier for pests?
The crop plants can't hide if they are placed in neat rows and fields.
5. How does plowing fields over and over damage the soils? Explain.
Plowing exposes soil to erosion- damages physical structure, leading to a decline in organic matter and loss of chemical elements.
6. What are the other 2 ways that agrocultures are harmful to ecosystems?
Agroculture lacks layers of soil-which can be made unsustainable from plowing.
The Plow Puzzle
7. How much of the top soil in the U.S. has been lost since European settlement?
One third of the top soil has been lost. 80 million hectares.
Can We Feed the World?
8. What percentage of the world’s land area is used for agriculture?
38%
How We Starve
9. What is the difference between undernourishment and malnourishment?
Undernourishment is when there are insufficient calories in food so the person has no energy to work. Malnourishment is when there is a lack of a specific chemical such as proteins or vitamins.
10. Why does providing food aid to countries in need actually work against increased availability of locally grown food?
The free food undercuts local farmers-making them unable to compete with it.
What We Grow on the Land
11. Most of the world’s food is produced by only 14 species. List them below in order of importance:
Wheat, rice, maize, potatoes, sweet potatoes, manioc, sugarcane, sugar beet, common beans, soybeans, barley, sorghum, coconuts, and bananas.
12. What is a forage crop?
Food grown for domestic animals.
13. Define the following:
- Rangelands: provides food for grazing and browsing animals without plowing and planting.
- Pastures: are plowed, planted and harvested to provide forage.
14. What impact does the number of livestock around the world have on rangeland and pasturelands?
More than 34 million kilometers are used for pastures worldwide-larger than size of Canada, U.S, Mexico, Brazil, Argentina, and Chile combined. Half of Earth's land area is used as a rangeland.
15. Why are feedlots considered to be a big source of local pollution?
Penned cattles are often crowded and are fed grain or forage. Manure builds up in large mounds and pollutes local streams.
16. What is a benefit of farming animals rather than crops?
Land too poor for crops, that people can eat, can be excellent rangeland with grasses and woody plants that domestic livestock can eat.
Soils
17. How does rainwater affect the soil horizon? Explain.
Rainwater is slightly acidic, when it moves down into soil, iron,calcium, magnesium, and other nutritionally important elements are leached.
18. What is soil fertility? How it is determined?
It is the capacity of a soil to supply nutrients necessary for plant growth.
19. Why are soils in humid and tropical areas considered to be poor? What happens to them after deforestation?
Soils in these areas have a poor amount of nutrients. After deforestation, it is hard for reforestation to occur.
20. What is the problem with soils in semi-arid regions?
Soils that accumulate certain clay minerals may swell and crack roads, walls, and buildings.
21. Why are coarse-grained soils more susceptible to erosion that soils that contain more clay?
Coarse-grained soils have small clay particles that retain water and retard the movement-causes the clay to erode.
22. Soil Horizons: Define each of the soil horizons
Horizon O: Upper horizon with the most organic material.
Horizon A:Upper horizon composed of both mineral and organic materials.
Horizon E: Composed of light-colored materials resulting from leaching of clay,calcium,magnesium and iron.
Horizon B: Enriched in clay, iron oxides, silica, carbonate or other material leached from overlying horizons.
Horizon C: Composed of partially altered parent material.
Horizon R: Unweathered parent material.
Restoring Our Soils
23. What is the difference between organic and inorganic (artificial) fertilizers?
Organic fertilizers are made naturally-improve both chemical and physical characteristics of soil. Artificial fertilizers are made industrially.
24. Define the following:
Macronutrient: Chemical element required by all living things in large amounts.
Micronutrient: Chemical element required in small amounts by all life forms or in moderate to small amounts for some forms of life.
Limiting Factor: A factor that is limiting and if that factor isn't improved, nothing else will make a difference.
Controlling Pests
25. In the U.S, how much of the potential harvest is lost to pests?
1/3 of potential harvest is lost to pests.
26. What is the definition of a weed?
Weeds are plants that are in places we do not want them to be.
Pesticides
27. What are the differences between inorganic and organic pesticides?
Inorganic pesticides are pesticides in forms of inorganic chemicals. Organic pesticides are made from organic compounds.
28. What are some of the reasons why pesticides are considered to be ineffective?
Pests can create a resistance and then can reproduce pests that can also have a resistance to that pesticide-that pesticide will no longer be of use.
29. Define Integrated Pest Management (IPM) AND explain HOW it works:
IPM is the idea that the goal can be control rather than complete elimination of a pest. It uses a combination of methods, including biological control, certain chemical pesticides and some methods of planting crops.
30. What is the use of biological control and give an example:
Biological control is use of one species that is a natural enemy to another. An example is BT-a disease to caterpillars.
31. What was the “green revolution”?
The "green revolution" were programs that led to development of new strains of crops with higher yields, better resistance to disease, or better ability to grow under poor conditions.
Genetically Modified Food: Biotechnology, Farming and Environment
32:. What are the 3 practices of genetic engineering?
1. Faster and more efficient ways to develop new hybrids.
2. Introduction of the terminator gene.
3. Transfer of genetic properties from widely divergent kinds of life.
33. What are the PROS and CONS of developing hybrid crops?
PROs-Can lead to hybrids that require less fertilizer, pesticide and water.
CONs-May produce superhybrids that can grow where they are not wanted and become pests.
34. What is the terminator gene and what does it do?
The terminator gene is a gene that terminates-makes seeds from a crop sterile and prevents GMOs from spreading.
35. What are the political and social concern with companies using seeds with terminator genes?
Terminator gene will allow U.S and corporations to control world food supply.
36. How are GMO (Genetically Modified Organisms) helpful?
GMOs can give food new nutrients and can give a higher crop yield than normal.
37. How can GMO’s be harmful?
GMOs can cause diseases to animals such as caterpillars and endangered species like monarch butterflies.
Aquaculture
38. What is aquaculture and how can it be helpful?
Aquaculture is farming of marine organisms-can provide food of high nutritional quality.
39. What is mariculture?
Farming of ocean fish-producing a small part of the total marine fish catch.
40. How can aquaculture and mariculture harmful to the environment?
Fishponds and marine fish release wastes polluting local environments. It can damage biodiversity.
Critical Thinking Issue: Will There Be Enough Water to Produce Food for a Growing
Population?
1: How might dietary changes in developed countries affect water availability?
If people in developed countries have diets that are more dependent on fruits and vegetables, then the demand for those items will go up. Higher demand for these foods mean more water that would need to be consumed to fit needs of people in those countries.
2. How might global warming affect estimates of the amount of water needed to grow crops in the 21st century?
If Earth's temperature increases, more droughts would occur. More droughts means more water needed for drinking and domestic use.
3. Withdrawing water from aquifers faster than the replacement rate is sometimes referred to as “mining water”. Why do you think this term is used?
The machines used in the process of withdrawing the water could be also used in mining for valuable minerals.
4. Many countries in warm areas of the world are unable to raise enough food, such as wheat, to supply their populations. Consequently, they import wheat and other grains. How is this equivalent to importing water?
The wheat and other grains grew with help of sunlight, air, and water.
5. Malthusians are those who believe that sooner or later, unless population growth is checked, there will not be enough food for the world’s people. Anti-Malthusians believe that technology will save the human race from a Malthusian fate. Analyze the issue of water supply for agriculture from both points of view.
Malthusian-populations grow, higher demand for food. This food requires water to grow-more food needed, more water needed to feed population.
Anti-populations grow, technology grows also. Better technology means better and more efficient ways to conserve water when demand is high.
Directions: Using the Soil Pyramid Program- Identify the Type of Soil with the Following Percent Compositions
- Sand: 30
Clay: 30
Silt: 40
Answer: Clay Loam
- Sand: 45
Clay: 10
Silt: 45
Answer: Loam
Directions: Determine the Type of Soils that are Characteristics of Each Specific of These Terrestrial Biomes and List Why?
Tundra: No true soils, Too cold of a layer and
Taiga (Boreal Forest): Podzolization, result of the acid soil solution produced under needleleaf trees
Temperate Broadleaf Deciduous: Brown forest soil, Hummus content of A and Horizon gives it a brown color
Mediterranean Scrub: Eroded soils because they are maintained by fires and goats.
Temperate Grassland: Dark brown, mild leaching, high organic content, and concentration of calcium carbonate in the B horizon
Scrubland: Light gray, Little hummus to give brown color
Tropical Rainforest: Oxisols, Severely leached, Rapid bacterial decay prevents hummus from building up
Tropical Savannah: laterization is the dominant soil-forming process and low fertility oxisols can be expected
Directions: Define and describe each of the alternative methods to traditional soil tillage
Windbreaks: Farmers plant trees along borders to cut down on wind erosion.
Cover Crops: Planting crops that grow during the most erosive fall and spring months. Winter crops act as a cover to protect from eroding soil.
Grassed Waterways: Farmers plant grassy strips to keep soil from running away with water.
Contour Cultivation: Farmers plant and cultivate their crops to follow contour of a field. It produces furrows that are at an angle to the field. Irregular surface makes it more difficult for water to erode soil.
Strip Cropping: Alternate a field with strips of different crops. A type of contour farming
Forages: Forage crops included in a rotation to cut down on erosion.
Conservation Tillage:Leaving stalks and leaves of harvested crops on their fields to protect soil from wind and rain.
No-Till: Farmers leave all of the last crop's residue while planting a new crop
Ridge Tillage: Forming soil into ridges and planting on ridges. Less likely to erode because the plant and soil material is not broken loose by machinery.