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Chapter 8 Land Resources and Uses

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1 Chapter 8 Land Resources and Uses

2 Wapusk National Park Just southeast of Churchill MB
Wild and remote landscape One of world’s largest polar bear maternity denning areas Supports wide variety of wildlife Current stressors include climate change, long-range transport of contaminants, and overabundant snow geese

3 Land Use Terrestrial land base of the Earth is 148,940,000 square kilometers Canada’s total land area 9,984,670 square kilometers (6%) 11% of land in Canada is owned privately 89% is crown land (provincial or federal government) Responsibility generally falls under provincial government

4 Agriculture in Canada One of the largest producers in the world
Exports over $24 billion worth of agricultural products Five largest sectors are grains and oilseeds, livestock, dairy, horticulture, poultry and eggs 5% of grain farms are reported as organic

5 Principle Types of Agriculture
Industrialized Agriculture: modern methods, large input of capital and energy and less land and labor than traditional methods Subsistence Agriculture: traditional methods, depend on labor and large amounts of land

6 Industrialized Agriculture
Modern agricultural methods Developed countries Inputs Capital Energy Chemicals High yields

7 Subsistence Agriculture
Traditional agricultural methods Developing countries Food for family Inputs Labor Land

8 Shifting Cultivation Subsistence agriculture
Grow crops, then leave land alone Slash-and-burn agriculture Clear forest Grow crops Soil loses productivity quickly Supports small populations

9 Nomadic Herding Subsistence agriculture Land not suitable for crops
Livestock continually move Why?

10 Intercropping Subsistence agriculture Variety of crops in same field
Polyculture Plants mature at different times Different crops harvested throughout the year

11 Agricultural Challenges
Loss of prime farmland Loss of domesticated varieties Improving yields Curbing environmental impacts

12 Loss of Agricultural Land
Land loss to urbanization and suburban sprawl

13 Loss of Domestic Varieties
Farmers using fewer varieties of plants and animals Modern methods Uniformity Maximum production Loss of genetic diversity Save germplasm Tissues May need later

14 Increasing Crop Yields
Food production has increased Green revolution Mid-20th century Modern methods High-yield varieties Chemicals

15 High-Yield Varieties Done with breeding and biotechnology

16 Green Revolution Benefits Mexico increased wheat production
Indonesia self-sufficient in rice Problems Developing countries dependent on chemicals, machinery High energy costs Too many chemicals

17 Increasing Crop Yields
Demand for grains will increase Can’t increase amount of land Yields can only increase so much Genetic engineering could help Developing countries will need better farming methods

18 Increasing Livestock Yields
Hormones Promote faster growth European Union limits imports of hormone-treated beef: why? Antibiotics Animals grow larger (4 – 5%) Resistant bacteria WHO wants them eliminated U.S. still using

19 Environmental Impacts
Air, water pollution Feedlot agriculture is the norm

20 Environmental Impacts
Pesticides Resistance Farmers use more Residues on food Land degradation Loss of productivity Salinization Habitat fragmentation

21 Environmental Impacts

22 Looking Towards The Future
Food requirements have been met Environmental problems increasing More food will be needed Vicious circle???

23 Controlling Agricultural Pests
Pest: interferes with human welfare or activities Pesticides Help control pests Insecticides Herbicides Fungicides Rodenticides

24 Problems With Pesticides
Genetic resistance 520 insect species resistant 84 weed species resistant Bioaccumulation Biomagnification Affect non-target species New pests may emerge Don’t stay put

25 Alternatives to Pesticides

26 Integrated Pest Management
Combination of control methods Keep crop loss to economically tolerable level Sustainable agriculture Management vs. eradication Education critical On the increase

27 Rangelands Grasslands not intensively managed Livestock grazing
Grasses, forbs, shrubs

28 Rangelands Vegetation has fibrous root system Grazing
Can be beneficial Carefully manage Can increase plant diversity Don’t exceed carrying capacity

29 Rangeland Degradation
Desertification Progressive degradation Result of overgrazing and drought On the increase

30 Canadian Rangelands Only 70 million acres are suitable for livestock grazing in Canada Under increasing pressure: why? Conservation easements Protect privately owned land from development Public rangelands Provincial crown land Agri-Environmental Services Branch

31 Public Canadian Rangelands
AESB manages 915,000 hectares of rangelands in Western Canada Conduct biodiversity inventories Management includes seeding, controlled burns, fence construction, rotational grazing, controlling invasive weeds, and protecting habitats of endangered species

32 Public Canadian Rangelands
Three essential service programs: Community Pasture Program Cover Crop Protection Program Prairie Shelter Belt Program

33 Forests Less than 1/3 Earth’s area What do we use forests for?
Ecosystem services Help regulate biogeochemical cycles “Carbon sinks” Release O2 Protect watersheds: how? Provide habitat

34 Forest Regions of Canada

35 Forest Management Traditional management Tree plantations Monocultures
Support fewer organisms: why? Low-diversity forests

36 Forest Management Sustainable forestry Practices vary
Environmentally balanced Maintain mix of trees Long-term conservation Wildlife corridors Connects areas Help some populations

37 Harvesting Trees 2005: 3.5 million cubic feet of wood harvested
Some burned directly Charcoal production Paper and wood products Some wood ecologically certified

38 Selective Cutting Mature trees cut individually or in small clusters
Forest remains essentially intact

39 Shelterwood Cutting Removal of all mature trees in an area over an extended period

40 Seed Tree Cutting Almost all trees removed from an area
Some left to provide seeds for regeneration

41 Clear-cutting All trees in an area are cut
Area reseeds naturally or planted Common and controversial

42 Clear-cutting

43 Deforestation Clearing large expanses of forests
Most serious problem facing forests today Why is this occurring? Most in Africa and South America

44 Results of Deforestation
Decreased soil fertility Increased soil erosion Desertification Increased extinction Regional and global climate changes: how?

45 Deforestation: Boreal Forests
Alaska, Canada, Scandinavia, Northern Russia Extensive by late 1980s Used for wood, wood fiber Annual loss = area twice as large as Brazil’s rain forests

46 Tropical Rain Forests Central & South America, Africa, SE Asia

47 Deforestation: Tropical Rain Forests
Subsistence agriculture Farmers follow roads Slash-and-burn Later used for ranching Commercial logging Cattle ranching Dam building Mining

48 Deforestation: Tropical Dry Forests
India, Kenya, Zimbabwe, Egypt, Brazil Fuelwood Charcoal production Very wasteful 4 tons wood  run smelter for 5 minutes

49 Important Minerals Sulfides: contain sulphur Oxides: contain oxygen
Metals Malleable, lustrous, conductors Iron, aluminum, copper Nonmetallic minerals Ore Rock with valuable mineral

50 Economy Enabled highly developed nations to become industrialized
Canada’s mineral and mining products accounted for over 17% the nations total domestic exports $40 billion toward the gross domestic product 369,000 jobs

51 Extracting Minerals Locate deposit Analyze mineral composition
Mine for minerals: many different ways Process mineral Make product

52 Surface Mining Near the surface Less expensive Overburden removed
Open-pit Dig quarry Iron, copper, gravel

53 Surface Mining Strip mining Dig trench to extract mineral
Dig parallel trench Cover old trench with new overburden Spoil bank

54 Subsurface Mining Minerals deep in ground Less land disturbance
More expensive More hazardous Shaft mine Direct vertical shaft Coal

55 Subsurface Mining Slope mine Slanting passage Ore hauled in cars

56 Mining & The Environment
Disturbs land Land prone to erosion  further damage Uses a lot of water Contaminated streams Acid-mine drainage

57 Impacts of Refining About 80% of mined ore made of impurities Tailings
Waste left behind Left in piles Toxic

58 Restoration of Mining Lands
When mine no longer profitable Prevents further degradation Filling in and grading the area Planting vegetation Large community restoration took place in Sudbury, Ontario in the early 1970’s

59 Soil: What Is It? More than just dirt!
Uppermost layer of Earth’s crust Mineral and organic matter Living organisms We depend on it: how?

60 Soil Formation Formed from parent material
Biological, chemical and physical weathering processes Continuous process Topography plays a role: how? Takes a long time

61 Soil Composition Four main parts Mineral particles Main component
From parent material Provides anchorage and minerals Organic matter Living or formerly living matter Humus Air Water

62 Soil Profile Look at horizons: layers O horizon: surface layer
A horizon: topsoil Deep in grassland soils Thinner in forest, tropical soils B horizon: subsoil C horizon: parent material Materials leach through the layers

63 Soil Profile

64 Soil Organisms

65 Soil Organisms Soil is alive!
Plant roots, insects, earthworms, moles, etc… Bacteria most numerous Fungi, algae, protozoa Provide ecosystem services: examples?

66 Decomposition Nutrient cycling
Pathway of nutrient minerals or elements Sign of balanced ecosystem

67 Soil Problems Our activities cause many problems Soil erosion
Mineral depletion Soil pollution Sustainable soil use Wise use of soil resources Keep soil productive for the future

68 Soil Erosion Movement of soil Natural process Accelerated today
Water, wind Major effects Loss of soil fertility Soil cannot retain as much water Runoff into bodies of water

69 Soil Erosion Poor soil management Agriculture, road building, logging
Plant cover limits erosion

70 Soil Pollution Physical or chemical change in soil
Adversely affects health of organisms Some from fertilizers, pesticides Salinization Result of irrigation Can render soil useless

71 Parks and Protected Areas
National parks are managed by Parks Canada Established in 1911 There were 42 National Parks and Park Reserves in Canada in 2010 National Parks cover 225,000 square kilometers, approximately 2% of total land mass National Marine Conservation Areas

72 National Parks of Canada

73 National Parks Primary goal is to protect the natural landscapes that occur in Canada’s 39 natural regions Protected under federal legislation, the Canada National Parks Act Managed primarily to protect and restore their ecological integrity Ecosystem management approach

74 National Parks 1989 the endangered spaces campaign was launched by Canadian Parks and Wilderness Society (CPAWS) and World Wildlife Fund of Canada National Marine Conservation Areas are managed for sustainable use.

75 Provincial Parks Managed by agencies within the government departments
Management plan is prepared for each park Face challenges of wildfires, wildlife imbalances, disease, and human impacts Each province has legislation to protect the provincial parks

76 Conservation in Parks Maintain ecological integrity
Preserve historical and commemorative places Promote conservation ethic Demonstrate conservation principles and approaches from United Nations reports The 12 Percent Challenge

77 Sustainable Agriculture
Maintains soil productivity: conservation techniques Healthy ecological balance Minimal long-term impacts Natural fertilizers

78 Sustainable Agriculture
Less chemicals and antibiotics Water and energy conservation Diverse crops

79 Sustainable Agriculture
Organic agriculture No non-natural chemicals No genetic engineering View the farm as an agroecosystem Second green revolution!

80 Genetic Engineering Move genes from one species to another
Could improve agriculture

81 Potential Benefits of GM Crops
Decrease nutritional deficiencies worldwide: Golden Rice Decreased use of pesticides Heartier plants Feed the world More productive farm animals Better animal vaccines

82 Potential Drawbacks of GM Crops
Cross-pollination with native species Widespread crop failure Food allergies Long-term impacts unknown

83 Conservation Tillage Residues from previous crops left in soil
Reduces erosion up to 70% Soil has more organic material Drawbacks?

84 Crop Rotation Planting a series crops in the same field over a period of years Decreases insect damage Reduces erosion Rotated crops depend on where you farm

85 Terracing Used on very steep slopes Like stairs Very expensive!

86 Other Methods Contour plowing
Farm with the natural contours of the land Strip cropping Strips of differing crops

87 Soil Reclamation Badly eroded land Prevent further erosion
Seed bare ground Plant shelterbelts Restore soil fertility Soil must recover first Restrict farming?

88 Soil Conservation Policies
Canada lagging behind In the United States, Food Security Act of 1985 Conservation Reserve Program (CRP) Voluntary program Take land out of production for 10–15 years Receive subsidy Reduced soil erosion Wildlife habitat

89 Eco Canada Career Focus
Consider a career as a remediation specialist Be involved in the planning of removing contamination from soil, groundwater, and other natural sites

90 Case Study: Industrial Ecosystems
Industrial ecology Efficient use of resources “Wastes” are potential products Mimic natural ecosystems Kalundborg, Denmark Link different industries

91 Kalundborg, Denmark

92 Case Study: Industrial Ecosystems
Takes many years to develop Economy and environment benefit: how?

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