2. What is Natural Capital ?
• Natural capital is the term used
for ‘natural resources’ which
can be exploited to produce
natural income of goods and
services.
• e.g. trees as timber that can be
harvested and sold for money.
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4. Natural Capital OF
EARTH
It includes the core and crust of
the earth, the biosphere itself teeming with forests, grasslands,
wetlands, tundra forests, deserts,
and other ecosystems - and the
upper layers of the atmosphere.
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5. NATURAL CAPITAL & INCOME
• The stock is the present accumulated quantity
of natural capital. It is a supply accumulated
for future use; a store.
• Natural capital is the term used for ‘natural
resources’ which can be exploited to produce
natural income of goods and services.
• e.g. trees as timber that can be harvested and
sold for money.
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6. • Natural capital provides a wide variety of valuable
ecosystem services including flood control, climate
stabilization, maintenance of soil fertility, and even
beauty and play.
• Globally, and within the bioregion, natural capital
is being depleted through over-harvesting,
development, poor agricultural practices, toxic
contamination, and other causes.
Human capture
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7. 3 TYPES OF NATURAL
CAPTIAL
oRenewable
oNon renewable
oReplenishable
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9. RECAP
•
•
•
•
What is Natural Resources?
What is Natural Capital?
Example of Natural Resources?
Types of Natural resources
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10. Values of Natural Capital:
• Economic value: can be determined from
the market price of the goods and services it
produces.
• Ecological value: have no formal market
price. Photosynthesis, nitrogen-fixation, soil
erosion control are essential for human
existance, but are taken for granted.
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11. • Aesthetic value: have not market price and
may not provide identifiable commodities,
so they are unpriced or undervalued from
an economic viewpoint.
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13. • Healthy ecosystems make very significant
economic contributions, but often in ways that
transcend conventional accounting.
• In order to maintain Natural Capital and the
services that it provides, the physical basis for the
productivity and diversity of nature must not be
systematically deteriorated.
Weak trees
removed
Clear cut
30
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Seedlings
planted
25
15
Years of growth 10 5
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14. Natural Capital can be protected through
careful application of:
• Ecological Land-Use to maintain habitat
quality and connectivity for all species.
• A connected system of wild lands can coexist
with productive rural areas and towns and
cities, with each part of the landscape
contributing to the stability of natural capital.
• Sustainable Materials Cycles prevent the
systematic contamination of living systems.
• Social Capital contributes to a culture of
sufficiency easing consumption pressures on
natural capital.
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15. Environmentalists have identified 5 basic causes
of environmental problems we face.
• Rapid population growth
• Unsustainable resource use
• Poverty
• Not including the environmental costs of economic
goods and services in their market prices
• Trying to manage and simplify nature with too little
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15
16. 3 TYPES OF NATURAL
CAPTIAL
oRenewable
oNon renewable
oReplenishable
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17. What is Renewable energy &
Nonrenewable energy?
• Renewable energy is energy which
comes from natural resources such
as sunlight, wind, rain, tides,
and geothermal heat, which
are renewable
• Nonrenewable energy is energy that
comes from the ground and is not
replaced in a relatively short amount of
time.
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20. RECAP
•
•
•
•
•
What is Natural Resources?
What is Natural Capital?
Example of Natural Resources?
Types of Natural resources
Environmentalists have identified 5 basic
causes of environmental problems we
face.
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21. What is Replenishable
energy?
• Replenishable energy is that energy
source that doesn’t reduce and gets
their replenishment of energies from
other natural sources like wind, sun,
trickling water, geothermal flows of
heat and biological processes
• Example:
• Water stores,Ground Water or surface
water
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22. Difference between renewable &non
renewable energy
Renewable Energy
1.
2.
3.
4.
Non Renewable Energy
The resources that can be renewed 1. The resources that are present
in fixed quantities are called
by reproduction are called
non-renewable resources.
renewable resources.
2. Non-renewable resources are
exhaustible.
Renewable resources are
inexhaustible.
3. Non renewable resources are
affected by human activities
4.
Renewable resources are not
Some abiotic resources are
affected by the human activities.
non-renewable.
For example- fossil fuels and
All biotic resources are
minerals.
renewable.
For example: air and water.
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25. What is Fossil fuels?
• Coal, oil and gas are called "fossil fuels"
becausethey have been formed from the
organic remains ofprehistoric plants and
animals.
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27. FOSSIL FUELS
SOURCE OF ENERGY
• Coal ,oil and natural gas are the three fossil
fuels.
They have two common characteristic
1. They were formed from the decomposition of
the remains of plants and animals.
2. It has taken millions of years for them to
accumulate and form deposit which are large
enough to be mined for human use
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29. Formation of Oil &Natural Gas
• These were formed from the decomposition of
plant and dead creatures, which collected in
layers on the sea bed.
• Each one rotted to form a tiny spot of oil.
• Their remains were covered by mud and sand.
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31. • As the sand was compressed into hard
sandstone rock, the oil and gas separated and
rose through the sandstone filling in the spaces
between the rock.
• Finally lighter gas rises to the top
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32. TOP 10 OILS COMPANIES
Rank
Company
1
2
National Iranian Oil Company
3
Qatar Petroleum
4
Iraq National Oil Company
5
Petróleos de Venezuela
6
Abu Dhabi National Oil Company
7
Kuwait Petroleum Corporation
8
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Nigerian National Petroleum Corporation
9
10
Libya NOC
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33. Advantage & Disadvantage of Fossil fuel
Advantages
1. Large amounts of
electricity can be
generated in one place
using coal, fairly cheaply.
2. Transporting oil and gas to
the power stations is easy.
3. Fossil fuels are very easy
to find.
4. Power stations that make
use of fossil fuel can be
constructed in almost any
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location.
Disadvantages
1. Basically, the main drawback of
fossil fuels is pollution. Burning
any fossil fuel produces carbon
dioxide, which contributes to the
"greenhouse effect“.
2.
It also produces sulphur dioxide, a
gas that contributes to acid rain.
3. Mining coal can be difficult and
dangerous. Strip mining destroys
large areas of the landscape.
4. Coal-fired power stations need
huge amounts of fuel, which
means train-loads of coal almost
constantly.
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35. What is Nuclear Energy?
• Nuclear energy originates from the splitting
of uranium atoms in a process called fission.
• At the power plant, the fission process is used
to generate heat for producing steam, which is
used by a turbine to generate electricity.
• Nuclear energy contributed only between 7 &
8 % of total world commercial energy
consumption .
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37. Nuclear Power plants
• A nuclear power plant (NPP) is
a thermal power station in which the
heat source is one or more nuclear
reactors.
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39. Nuclear Power plants in India
• Nuclear power is the fourth-largest source
of electricity in India after thermal, hydroelectr
ic and renewable sources of electricity.
• As of 2010, India has 20 nuclear reactors in
operation in six nuclear power plants,
generating 4,780 MW.
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41. Is Nuclear Power plants is safe ?
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42. SAFETY OF NUCLEAR
POWER PLANT
• Scientist have repeatedly emphasized how safe
nuclear power is ,but they have not been able
to convince most .
• Public confidence is nuclear power was
shattered by the great explosion in 1986,at
chernobl in the Ukraine
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44. countries produce the most nuclear
power?
Huge demand for power
No coal left,very little oil & gas
Major industrial country;has little coal,no oil and gas
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45. Advantage & Disadvantage of Nuclear Energy
Disadvantage
Advantage
1. Does not produce smoke or
carbon dioxide, so it does not
contribute to the greenhouse
effect.
2. Produces huge amounts of
energy from small amounts of
fuel.
1. Nuclear plants are more
expensive to build and
maintain.
2. Waste products are
dangerous and need to be
carefully stored for long
periods of time.
3.
3. Produces small amounts of
waste.
4. Nuclear power is reliable.
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Nuclear power plants can
be dangerous to its
surroundings and
employees.
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48. What is alternative source of energy?
• An alternative source usually refers to an
energy source that can be used as a
replacement for fossil fuels.
• Most alternative sources are also renewable
sources of energy
• They are also SUSTAINABLE sources of
energy, which means that people will be able to
use long after fossil fuels run out.
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51. Most common types of alternative energy
1. Solar energy is generating of electricity from the sun
2. Wind energy is generating of electricity from the
wind
3. Geothermal energy is using hot water or steam from
the Earth’s interior for heating buildings or electricity
generation.
4. Biofuel and ethanol are plant-derived substitutes of
gasoline for powering vehicles
5. Wave : force of the sea waves as they break against
the coastline
6. Biomass: using fuel wood, crop wastes and animal
dung as fuel
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52. What is biomass?
• Biomass, as a renewable energy source,
is biological material from living, or recently
living organisms.
• As an energy source, biomass can either be
used directly, or converted into other energy
products such as biofuel.
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55. Advantage & Disadvantage of Biomass
Advantages
1. Theoretically
inexhaustible fuel source
2.
Minimal environmental
impact
3. Alcohols and other fuels
produced by biomass are
efficient, viable, and
relatively clean-burning
Disadvantages
1. Still an expensive
source, both in terms of
producing the biomass
and converting it to
FUEL
2. On a small scale there is
most likely a net loss of
energy--energy must be
put in to grow the plant
mass
4. Available throughout the
world
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61. Advantage & Disadvantage of Solar Energy
Advantage
Disadvantage
1. Solar energy is free - it needs
no fuel and produces no waste
or pollution.
2. Solar cells make absolutely no
noise at all.
3. Solar powered panels and
products are typically
extremely easy to install.
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1. The Solar Cells and Solar
Panels that are needed to
harness solar energy tend to
be very expensive
2. Solar power cannot be
harnessed during a storm,
on a cloudy day or at
night.
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64. What is Geothermal Energy?
• Geothermal means earth-heat. It is related to
the thermal energy of Earth’s interior.
• On a large scale, the intensity of this thermal
energy increases with depth, that is, the
temperature of the Earth increases as we travel
closer to its centre.
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65. How it works?
• Hot rocks underground heat water to produce
steam.
• We drill holes down to the hot region, steam
comes up, is purified and used to drive turbines,
which drive electric generators.
• There may be natural "groundwater" in the hot
rocks anyway, or we may need to drill more holes
and pump water down to them.
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66. Advantage & Disadvantage of GeoThermal Energy
Advantage
Disadvantage
1. Geothermal energy does not
produce any pollution,
1. Not universally available.
2. The power stations do not take
up much room, so there is not 2. High Cost:
much impact on the
environment.
3. No fuel is needed.
4. Once you've built a geothermal
power station, the energy is
almost free.
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72. What is HYDRO POWER?
• Hydropower or water power is power that is
derived from the force or energy of moving
water
• The production of electrical power through the
use of the gravitational force of falling or
flowing water
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75. WORKING PROCESS
• Most hydroelectric power (HEP) comes from
the potential energy of dammed water driving
a water turbine and generator.
• The power extracted from the water depends on
the volume and on the difference in height
between the source and the water's outflow.
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78. Advantage
Disadvantage
1.
Once the dam is built, the energy
is virtually free.
2.
No waste or pollution produced.
3.
Finding a suitable site can be
difficult - the impact on residents
and the environment may be
unacceptable.
4.
Water can be stored above the
dam ready to cope with peaks in
demand.
Building a large dam will flood a
very large area upstream, causing
problems for animals that used to
live there.
Water quality and quantity
downstream can be affected, which
can have an impact on plant life.
Much more reliable than wind,
solar or wave power.
4.
The dams are very expensive to
build.
2.
3.
1.
5.
Electricity can be generated
constantly.
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80. What is Wind Energy?
• Wind energy is energy that is created by using
the wind to generate power.
• It is a form of kinetic energy that can be
transformed into mechanical energy or
electricity.
How it works?
• Wind turbines transform the energy in the wind
into mechanical power, which can then be used
directly for grinding etc. or further converting to
electric power to generate electricity.
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84. Where you can see?
• On hill tops and other areas of open high
ground
• Along the coastline
• Offshore(in the sea) but close to the coast
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85. Top 10 countries by windpower capacity (2010)
MW
China
44,733
United States
40,180
Germany
27,215
Spain
20,676
India
13,066
Italy
5,797
France
5,660
United Kingdom
5,204
Canada
4,008
Denmark
3,734
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86. Advantage
Disadvantage
1.
Wind is free, wind farms need
no fuel.
1. The wind is not always predictable some days have no wind.
2.
Produces no waste or
greenhouse gases.
2. Suitable areas for wind farms are
often near the coast, where land is
expensive.
3.
The land beneath can usually
still be used for farming.
4.
Wind farms can be tourist
attractions.
5.
3. Some people feel that covering the
landscape with these towers is
unsightly.
A good method of supplying
energy to remote areas.
4. Can kill birds - migrating flocks t
5. Can affect television reception if you
live nearby.
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88. What is Ecological Footprint?
• The ecological footprint is a measure of human
demand on the Earth's ecosystems.
• An ecological footprint measures the total amount
of land and resources used, it includes
your carbon footprint but goes further
• It represents the amount of biologically
productive land and sea area necessary to supply
the resources a human population consumes, and
to assimilate associated waste.
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88
90. Ecological footprint?
• Using this assessment, it is possible to estimate
how much of the Earth it would take to support
humanity if everybody followed a given
lifestyle.
• It is a standardized measure of demand
for natural capital that may be contrasted with
the planet's ecology
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94. Ecological footprints can be
increased by:
1. Greater reliance on fossil fuels
2. Increased use of technology and energy (but
technology can also reduce the footprint)
3. High levels of imported resources (which have
high transport costs)
4. Large per capita production of carbon waste
(high energy use, fossil fuel use)
5. Large per capita consumption of food
6. A meat-rich diet
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95. Ecological footprints can be
reduced by:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
reducing use of resources
recycling resources
reusing resources
improving efficiency of resource use
reducing amount of pollution produced
transporting waste to other countries to deal with
improving country to increase carrying capacity
importing resources from other countries
reducing population to reduce resource use
using technology to increase carrying capacity
using technology to intensify land
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95
97. 3.8.3: Describe and explain the differences between the
ecological footprints of two human populations, one from an
LEDC and one from a MEDC
• LEDCs have small ecological footprints as MEDCs
have much greater rates of resource consumption.
• This is partly because MEDCs have higher incomes and
the demands for energy resources is high. MEDCs
consume a lot of resources as they are wasteful, they
also have more waste and pollution.
• LEDCs are the opposite with lower consumption as
people do not have too much to spend. The economy of
the country forces them to recycle many resources,
however they are developing and they’re ecological
footprint is increasing.
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101. What is Intrinsic value?
• Intrinsic values, in relation to ecosystems,
means those aspects of ecosystems and their
constituent parts which have value in their own
right, including:
• (a) Their biological and genetic diversity; and
• (b) The essential characteristics that determine
an ecosystem's integrity, form, functioning,
and resilience.
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102. Intrinsic value?
• Environmentalists argue that every part of
the ecosystem has intrinsic value.
• This means that although living things may have
no monetary value to human beings, they have
significant worth in other ways.
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104. Environment have its own Intrinsic value
In the modern world, many governments look
at the economic value of an aspect of the
environment when making policy decisions.
Those who believe in intrinsic value would
say that though an endangered species or
a rainforest may not provide any use or value
for people, they have inherent worth
nonetheless.
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109. What is Sustainable development?
• Sustainable development is development that
meets the needs of the present without
compromising the ability of future generations
to meet their own needs. It contains within it
two key concepts:
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111. • the concept of needs, in particular the essential
needs of the world's poor, to which overriding
priority should be given; and
• the idea of limitations imposed by the state of
technology and social organization on the
environment's ability to meet present and
future needs."
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111
114. • Sustainability is the extent to which a given
interaction with the environment exploits and uses the
NATURAL INCOME without causing long term
deterioration of NATURAL CAPITAL.
• Harvesting renewable or replenishable resources at a
rate that will be replaced by natural growth.
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115. Which one is Sustainable Yield?
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115
116. Sustainable Yield
• Rate of increase in NATURAL CAPITAL.
• Amount which can be exploited without depleting
the original stock or its potential to be
replenished.
• Exploitation must not affect long term
productivity.
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117. Calculation of SY
• Gain in biomass over time through growth and
recruitment (addition of individuals to the
population).
• Can express as energy rather than biomass.
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117
121. What is SOIL?
• Soil is a natural body consisting of layers
of mineral constituents of variable thicknesses, which
differ physical, chemical, and
mineralogical characteristics
• Soil is composed of particles of broken rock that have
been altered by chemical and mechanical processes
that include weathering and erosion.
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122. Soil formation is a slow process:
1. Weathering of rock (mechanical).
2. Deposition of sediments by erosion
(mechanical).
3. Decomposition of organic matter in
dead organisms (chemical).
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125. These top two layers are most fertile, have the highest
concentration of organic matter, and contain large amounts of
living organisms.
Rove beetle
Pseudoscorpion
Flatworm
Centipede
Ant
Adult
fly
Fly
larvae
Ground
beetle
Mite
Roundworms
Beetle
Protozoa
Mite
Springtail
Millipede
Bacteria
Sowbug
Slug
Fungi
Snail
Actinomycetes
Mite
Earthworm
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126. “B” (subsoil) and “C” (parent material)
HORIZON contain most of the soil’s
inorganic matter, broken-down rock.
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127. • Soil has four basic constituents
1. Organic matter: living plants and
animals and their dead remains and
wastes
2. Mineral matter: mainly sand, silt and
clay
3. Water
4. Air
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128. Soil Content
•
•
•
•
Clay (very fine particles)
Silt (fine particles)
Sand
Gravel (coarse to very coarse particles)
SOIL TEXTURE is determined by the relative amounts
of the different types and sizes of mineral particles.
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133. Properties of Soils with Differ
Texture
Nutrient
Capacity
Infiltration
WaterHolding
Capacity
Aeration
Workability
Clay
Good
Poor
Good
Poor
Poor
Silt
Medium
Medium
Medium
Medium
Medium
Sand
Poor
Good
Poor
Good
Good
Loam
Medium
Medium
Medium
Medium
medium
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135. SOIL PROFILE
• Soil Profile refers to the layers of soil;
• Horizon A, B, and C.
• Horizon A refers to the upper layer of soil,
nearest the surface. It is commonly known as
topsoil.
• Horizon A provides plants with nutrients they
need for a great life
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136. • The layer below horizon A, of course, has to
be horizon B
• The subsoil is the horizon B
• This is where materials accumulates from
horizons above & below
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137. • Horizon C consists mostly of weatherized big
rocks.
• This contains many loose pieces of rock,
broken off from the parent rock below
weathering
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141. • Soil minerals play a vital role in soil fertility
since mineral surfaces serve as potential sites
for nutrient storage.
• There are numerous types of minerals found in
the soil.
• These minerals vary greatly in size and
chemical composition.
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142. Soil texture
• Soil texture is a qualitative classification tool
used in both the field and laboratory to
determine classes for agricultural soils based
on their physical texture.
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144. SOIL PERMEABILITY is the rate at which water and
air move from upper to lower soil layers.
Water
Water
High permeability
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145. Nitrogen fixing
by lightning
Pathway of
plant
nutrients in
soil.
Crop
plant
Organic fertilizers,
animal manure,
green manure, compost
Commercial
inorganic
fertilizer
10-6-4
N-P-K
Dead
organic matter
Nitrogen fixing
Application
to land
Decomposition
Nutrient removal
with harvest
Absorption of nutrients
by roots
Supply of
available plant
nutrients in soil
Nutrient loss
by bacterial
processes
such as
conversion
of nitrates to
nitrogen gas
Weathering
of rock
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by bacteria
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Nutrient loss
from soil erosion
145
146. Desertification is the enlargement of
deserts through human activities.
Consequences
Causes
Overgrazing
Worsening drought
Deforestation
Famine
Surface mining
Economic losses
Erosion
Lower living
standards
Salinization
Environmental
refugees
Soil compaction
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147. •
•
•
•
•
•
•
•
•
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October summative : 22.10.2012(Monday)
Marks:60
Format: Paper 2
Syllabus:
Ecological footprint
Intrinsic value
Sustainable development &Yield
Calculation of Sustainable Yield
SOIL &FOOD SYSTEM
Book page numbers:192 to 253
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148. EOST 2012
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Thursday, 22nd,November
Time :11.30 am-1.00 pm
Syllabus:
Topic 3: Human population, carrying capacity and resource
use
3.1 Population dynamics
3.2 Resources—natural capital
3.3 Energy resources
3.4 The soil system
3.5 Food resources
3.6 Water resources
3.7 Limits to growth
3.8 Environmental demands of human populations
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149. What is Leaching?
• Leaching refers to the loss of watersoluble plant nutrients from the soil,
due to rain and irrigation.
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153. What is Soil Degradation?
• Soil degradation is the decline in quantity and
quality of soil.
• It includes erosion by wind and water,
biological degradation(e.g. the loss of humans
and plant or animal life)
• Physical degradation(loss of structure, changes
in permeability)
• Chemical degradatrion(acidification,declining
fertility,changes in ph & salinity)
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155. Types of Soil Degradation
• There are three main types of soil degradation:
1. Soil erosion,
2. Desertification, and
3. Salinization.
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157. What is Soil erosion?
• Soil is naturally removed by the action of
water or wind or
• Soil erosion is when the soil is blown away by
the wind or washed away by the rain.
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158. 1.Soil Erosion
Causes of soil erosion
• Water can cause soil erosion. Rainfall is an example of
water causing soil erosion.
• The lack of permanent vegetation cover in certain
locations can cause soil erosion due to the wind.
• Human activities such as farming, logging, and
constructions also cause soil erosion.
Consequences of soil erosion
• Soil erosion can lead to poor crop growth and yield
reductions in areas of fields.
• Loss of soil fertility through depletion of plant nutrients
in top soil.
• Soil quality, structure, stability and texture can be
affected by the loss of soil.
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163. What is Soil Desertification?
• Desertification is the development of desert-like
conditions in regions that have experienced
human disturbance such as deforestation,
overgrazing, or poorly managed agriculture.
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165. 2.Desertification
Causes of desertification
• Natural climate change that causes prolonged
drought.
• Human activities that reduce or degrade top soil.
• Increased population and livestock pressure on
marginal lands accelerates desertification.
• Deforestation
Consequences of desertification
• Economic loses
• Lower living standards
• Major threat to biodiversity
• Prolonged droughts
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166. Lake Chad in a 2001 satellite image, with the actual lake in blue.
The lake has shrunk by 95% since the 1960s
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169. 3.Salinization
Causes of Salinization
• High level of salt in the soils
• Over cultivation
• Irrigation mismanagement
• Climate trends that favor accumulation
Consequences of Salinization
• Stunts crop growth
• Lowers crop yields
• Destroys fertility and plants
• Damage to infrastructure (i.e. roads, bricks etc.)
• Reduction of water quality
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177. 1.PLANTING TREES
• Roots of trees firmly hold on to the soil. As
trees grow tall, they also keep rooting deeper
into the soil.
• As the roots of trees spread deep into the
layers of soil, they hold it tightly, thus
preventing soil erosion.
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178. 2. No-till Farming
• The process of preparing soil for plowing is known as tilling.
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No-till farming is a way of growing crops without disturbing it
through tillage.
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The process of tilling is beneficial in mixing fertilizers in the
soil, making rows and preparing the surface for sowing.
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179. 3.Crop Rotation
• Some pathogens tend to build up in soil if the
same crops are cultivated again and again.
• To save the soil from these adverse effects,
crop rotation is practiced.
• It is a method of growing a series of dissimilar
crops in an area. Crop rotation also helps in
the improvement of soil structure and fertility.
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180. 4. Build Terraces
• A terrace is a leveled section of a hilly
cultivated area.
• Owing to its unique structure, it prevents rapid
surface runoff of water.
• Terracing gives the landmass a stepped
appearance, thus slowing the washing down of
soil.
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181. 5. Water the Soil
• Watering soil is a good measure of soil
conservation.
• Watering the soil along with plants growing in
it is a way to prevent soil erosion caused by
wind.
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182. 6. Salinity Management
• The salinity of soil increases due to excessive
accumulation of salts in the soil.
• The salinity of soil is detrimental to the
vegetative life in it.
• The death of vegetation leads to soil erosion.
Hence, salinity management is an indirect way
of conserving soil.
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