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1. Land & Energy
Resources
BY,
SHUJAAT ALI QASMI …AR-048

2. WHAT IS A RESOURCE
 A resource is a source or supply from which benefit is produced.
Typically resources are materials, energy, services, staff, knowledge,
or other assets that are transformed to produce benefit and in the
process may be consumed or made unavailable. Benefits of
resource utilization may include increased wealth, meeting needs or
wants, proper functioning of a system, or enhanced well being.
From a human perspective a natural resource is anything obtained
from the environment to satisfy human needs and wants.

3. LAND
 Land, sometimes referred to as dry land, is the solid surface of
the Earth that is not permanently covered by water.[1] The vast
majority of human activity occurs in land areas that
support agriculture, habitat, and various natural resources.
 Some life forms (including terrestrial plants and terrestrial animals)
have developed from predecessor species that lived in bodies of
water.

4. LAND MASS
 "Land mass" refers to the total surface area of the land of a
geographical region or country (which may include discontinuous
pieces of land such as islands). It is written as two words to distinguish
it from the usage "landmass", the contiguous area of land
surrounded by ocean.
 The Earth's total land mass is
148,939,063.133 km2 (57,505,693.767 sq mi) which is about 29.2% of its
total surface. Water covers approximately 70.8% of the Earth's
surface, mostly in the form of oceans and ice formations.

11. Soil, a limited
resource we
depend upon,
but take for
granted

12. Soil Erosion
 What causes soil erosion?
 How serious of a problem is it?
 Good news and bad news from the U.S.
 What is desertification?
 How do salts degrade the soil?

13. Wind
Water
People
WHY
CARE
about
soil
erosion?
CAUSES OF SOIL EROSION

14. Impacts of Soil Erosion
 Loss of soil fertility
 Sediment runoff causes problems in surface
water (pollution, clog ditches, boat channels,
reservoirs)
 #1 source of U.S. water pollution
 Renewable only on LONG timeframes (200-
1,000yrs. for 1 inch)

15. Soil Erosion
On Agricultural land in U.S. today, soil is eroding 16 times faster
than it is created!!!

16. Areas of serious concern
Areas of some concern
Stable or nonvegetative areas
Global Soil Erosion
Fig. 14-7 p. 280

17. Causes of Desertification
Overgrazing
Deforestation
Erosion
Salinization
Soil Compaction
Natural Climate Change

18. World Desertification
Fig. 14-9 p. 282

19. Desertification: causes and
consequences.
•Occurring on 1/3 of world’s land

20. 1. Irrigation
water
contains small
amounts of
dissolved salts
2. Evaporation
and
transpiration
leave salts
behind
3. Salt builds up
on soil
SALINIZATION:

22. Reducing and Cleaning Up
Salinization
Reduce irrigation
Switch to salt-tolerant crops
Flush soils
Not growing crops for 2-5 years
Install underground drainage

23. Soil Degradation on Irrigated Land
1. Precipitation and
irrigation water
percolate
downward
2. Water table rises
3. Bad for roots
Evaporation
Transpiration
Evaporation
Waterlogging
Less permeable
clay layer
Fig. 14-11 p. 283

26. What controls soil productivity?
 Water -infiltration, drainage, storage
 Nutrients/toxins (12/17)
 Gas Exchange -CO2 out, O2 in
 Strength/rooting volume
 Waste Disposal
 Seed/seedling nursery

27. Where is the best soil?

28. Where are the productive soils?
We see what we know. The more we know,
the more options we realize we have with
the world’s soils.

29. What are some threats?
 Finite arable land: 1.1 billion hectares
 1961 0.32 ha/p; today 0.15 ha/p; 2050 0.12 ha/p
 Erosion – today 12-40 Mg/ha  30% agricultural lands irreversibly
damaged.
 Desertification – e.g., 27% China affected w/ new 2500 km2/yr.
 Salinization- affects 20% of world’s 250+ million hectares of irrigated
lands.
 Contamination w/ heavy metals.
 Urbanization and other competing uses.
 Problematic off-site issues & competing uses.

30. Soil Conservation
 What is soil conservation and how does it work?
 What are some methods for reducing soil
erosion?
 Inorganic versus organic fertilizers

31. Soil Conservation
Involves many ways of reducing soil erosion and restoring fertility to
soil.

32. Conventional Tillage
Farmers plow the land and then
break up and smoothes soil to
make a planting surface
 Leaves soil vulnerable to erosion
 Midwest tillage often down in fall
(winter bare)

33. Conservation Tillage
Disturbing the soil as little as possible
while planting crop
 Not tilling over winter
 Planting without disturbing soil
 Special equipment “inject” soil with
seed, fertilizer etc.
 In 2003 45% of U.S. farms

34. Terracing
Used on
steep
slopes
Reduces
erosion
and
water loss

36. Contour
planting
Planting
crops in
rows across
the slope
Strip
Cropping
Alternating
crops from
row crops
and crops
that
Cover Crops: can be
planted right after harvest
to hold onto soil during
winter

38. Alley Cropping: several cops planted together in
rows (alleys) Increases shade (less water)
Provide windbreaks

39. Windbreaks

40. SOIL RESTORATION
 Organic fertilizer
 Commercial inorganic fertilizer
 Animal
manure
 Compost
 Crop rotation

41. Organic Fertilizer
Has decreased in the
U.S. due in part
because most
farmers no longer
raise livestock and it
costs too much to
transport
 Poop Factory and
Phillies Soil
 Inorganic fertilizers
have taken off

42. Inorganic Fertilizers
Nitrogen, Phosphorous,
Potassium
 Grown in usage
worldwide
 Credited with
increasing crop yields
(1/4 of world crops)
 W/o could only feed 2-
3 billion people
 Many problems
associated (see next
slide)

43. ENERGY RESOURCES

44. Energy Resources
 Supplementing free solar energy
 99% of heat comes from the sun
 Without the sun, the earth would be –240 0C (-400 0F)
 We supplement the other 1% with primarily non-renewable
energy sources

45. Energy Resources
 Renewable (16%)
 Solar
 Wind
 Falling, flowing
water
 Biomass
 Non-renewable
(84%)
 Oil
 Natural gas
 Coal
 Nuclear power

46. Energy sources and uses
 Energy uses in developed countries
 industrial
 domestic
 transportation
 Note: Electricity is not an energy source,
converted from another source (coal,
hydro, nuclear, etc.).

47. Evaluating Energy Resources
 Renewable
 Future availability
 Net energy yield
• It takes energy to get energy
 Habitat degradation
 Cost (initial and ongoing)
 Community disruption
 Political or international issues
 Suitability in different locations
 Polluting (air, water, noise, visual)

48. Each type of power project needs to be evaluated
for the benefits and costs

49. The environmental costs of hydroelectricity are much
different than windpower, for example

50. Important Nonrenewable Energy
Sources

51. OIL and NATURAL GAS
 Accumulations of dead marine organisms on the ocean
floor were covered by sediments.
 Muddy rock gradually formed rock (shale) containing
dispersed oil.
 Sandstone formed on top of shale, thus oil pools began
to form.
 Natural gas often forms on top of oil.
• Primary component of natural gas is methane

53. Natural Gas
 50-90% methane
 Cleanest of fossil fuels
 Approximate 200 year
supply
 Advantages and
disadvantages

54. Coal – What is it?
 Solid fossil fuel formed in several stages
 Land plants that lived 300-400 million
years ago
 Subjected to intense heat and pressure
over many millions of years
 Mostly carbon, small amounts of sulfur

55. Coal Formation and Types

56. Coal – what do we use it for?
 Stages of coal formation
• 300 million year old forests
• peat > lignite > bituminous > anthracite
• Primarily strip-mined
 Used mostly for generating electricity
• Used to generate 62% of the world’s electricity
• Used to generate 52% of the U.S. electricity
 Enough coal for about 200-1000 years
• U.S. has 25% of world’s reserves
 High environmental impact
 Coal gasification and liquefaction

57. Nuclear Energy
 Fission reactors
 Uranium-235
 Fission
• Resulting heat
used to produce
steam that spins
turbines to
generate
electricity
• Produces
radioactive
fission fragments
Light water generator – used in
all U.S. and 85% world wide.
Great danger of
losing coolant!

58. The Nuclear Fuel Cycle
Produces highly radioactive
materials that must be stored
safely for 10,000-240,000 years.

59. Energy Efficiency and Renewable
Energy
 84% of energy is wasted
 41% degradation
 43% unnecessary
 Fuel wasting vehicles
 Furnaces
 Poorly insulated buildings

60. Energy Efficiency and Renewable
Energy
 Four primary energy wasters:
Incandescent light bulb 95%
Nuclear Power – 86%
Cars – 75-80%
Coal – 66%

61. Energy Efficiencies – do more with
less!

62. Renewable energy sources
 Solar
 Flowing water
 Wind
 Biomass
 Geothermal
 Hydrogen

63. Using Solar Energy to Provide Heat
Passive solar heating Active solar heating

64. Producing Electricity from Wind

65. Producing Energy from Biomass
 Biomass and biofuels
 Biomass plantations
 Crop residues
 Animal manure
 Biogas
 Ethanol
 Methanol

66. Geothermal Energy
 Geothermal heat pumps
 Geothermal exchange
 Dry and wet steam
 Hot water
 Molten rock (magma)
 Hot dry-rock zones

67. The Hydrogen Revolution
 Environmentally friendly
 Extracting hydrogen efficiently
 Storing hydrogen
 Fuel cells

68. Solutions: A Sustainable Energy
Strategy