about soil carbon sequestration

1. soil carbon sequestration and carbon trading

2. ORGANIC MATTER
(DECOMPOSITION POOLS)
Residues
Labile pool
Readily decomposed
Low C:N ratio
Sugar, protein, starch
Intermediate pool
Resists decomposition
Intermediate C:N ratio
Cellulose, hemicellulose Resistant pool
Very resistant to
decomposition
High C:N ratio
Lignin
(Humus)

3. Carbon cycle

4. Carbon cycle:
 Carbon is a common constituent of all organic
matter.
 It is involved in all life processes.
 The transformation of this element into
various organic materials like CO2, plants, and
animals and their dead residues is called
carbon cycle.
 This is also the biocycle or life cycle. This
insures the continuity of life on earth.

5.  Plants take up atmospheric CO2 during
photosynthesis in the presence of light and
convert it into various organic components
 Humans and animals consume plant products,
derive energy and develop body tissue.
 They return the wastes and residues to the soil
macro and micro organisms digest these
organic residues.
 They release plant nutrients for plants and also
CO2.
 The CO2 is released to the atmosphere.
 The CO2 released to the atmosphere is
available for plant consumption.

6. THE NITROGEN CYCLE
Atmospheric
nitrogen
Atmospheric
fixation
and deposition
Animal
manures
and biosolids
Industrial fixation
(commercial fertilizers)
Crop
harvest
Volatilization
Denitrification
Runoff and
erosion
Leaching
Organic
nitrogen
Ammonium
(NH4)
Nitrate
(NO3)
Plant
residues
Biological
fixation by
legume plants Plant
uptake
Input to soil
Component Loss from soil
-
+

7. C : N Ratio
 The ratio between the nitrogen content in the microbes and in the
organic residues and to the carbon content is called as C:N ratio
 When fresh plant residues are added to the soil they are rich in
carbon and poor in N.
 This results in wider C:N ratio (40:1) decomposition of the
organic matter in the soil changes to humus resulting in a narrow
C:N ratio (10:1).
 When materials high in carbon are added to the soil the
microbial population increase due to the plentiful supply of food
material.

8.  A lot of CO2 is released.
 During this process the micro organisms utilize
the soil N for their body build up and there is a
temporary block of N.
 When the decomposition of fresh organic
residues reaches to the stage where the C:N
ratio is 20:1 there is an increase in the
availability of N.

9.  The C, N ratio of cultivated soils ranges from
8:1 to 15:1.
 Average 10:1 to 12:1.
 Legumes and Farm manure 20:1 – 30:1.
 Straw 100:1
 Saw Dust 400:1
 In micro organisms 4:1 to 9:1

10.  There exists a relationship between the organic
matter and N content. soil carbon has a definite
proportion of the organic matter.
 Hence the C to N ratio in soils is fairly constant .
 The C:N ratio is lower in soils of arid regions
than humid regions.
 C:N ratio is smaller in subsoils.

11. Biomass carbon
It is defined as part of the carbon assimilated by
the microorganisms and incorporated into the
microbial tissue ( microbial biomass)
Biomass nitrogen
It is defined as part of the nitrogen assimilated by
the microorganisms and incorporated into the
microbial tissue ( microbial biomass)

12. Carbon Sequestration and Carbon Trading
 Carbon sequestration is the process of
removing atmospheric CO2, either through
biological processes (eg plants and trees), or
geological processes through storage of CO2 in
underground reservoirs.
 Carbon sequestration refers to the storage of
carbon in a stable solid form.
 It occurs through direct and indirect fixation of
atmospheric CO2.

13. What is meant by carbon sequestration?
 Carbon sequestration is the process of
transforming carbon in the air (CO2) into stored
soil carbon.
 Carbon dioxide is taken up by plants through the
process of photosynthesis and incorporated into
living plant matter.
 As the plants die, the carbon-based leaves, stems
and roots decay in the soil and become soil
organic matter
 . This is the basic process called carbon
sequestration.

14. Greenhouse gases
Carbon dioxide is the
largest single
contributer to climate
forcing
Carbon dioxide
contributes about half
of total climate forcing
from greenhouse
gases

15.  Direct soil carbon sequestration
 Direct plant carbon sequestration
 Indirect Plant biomass sequestration
 The amount of carbon sequestered at a site
reflects the long-term balance between carbon
uptake and release mechanisms.

16. How can carbon sequestration help reduce
global warming?
 Atmospheric carbon dioxide and other
greenhouse gases act to trap heat that is
reflected from the earth’s surface.
 This buildup of heat could lead to global
warming.
 Through carbon sequestration, atmospheric
carbon dioxide levels are reduced as soil
organic carbon levels increase.

17. How much impact can carbon sequestration
have on greenhouse gases?
It has been estimated that 20 percent or
more of targeted CO2 emission reductions
could be met by agriculture soil carbon
sequestration.

18.  If the soil organic carbon is undisturbed, it
can remain in the soil for many years as
stable organic matter
 This carbon is then sequestered or removed
from the pool available to be recycled to the
atmosphere.
 This process reduces CO2 levels in the
atmosphere, reducing the chances of global
warming.

19. Soil Carbon Sequestration
 Soil carbon sequestration is the process of
transferring carbon dioxide from the
atmosphere into the soil through crop
residues and other organic solids, and in a
form that is not immediately reemitted.
 This transfer or “sequestering” of carbon
helps off-set emissions from fossil fuel
combustion and other carbon-emitting
activities while enhancing soil quality and
long-term agronomic productivity.

20. Carbon capture and storage (CCS) Technologies
 It is an approach to mitigate global warming
based on capturing carbon dioxide (CO2)
from large point sources such as fossil fuel
power plants and storing it instead of
releasing it into the atmosphere.

21. CCS applied to a modern conventional power
plant could reduce CO2 emissions to the
atmosphere by approximately 80-90%
compared to a plant without CCS.
Capturing and compressing CO2 requires
much energy and would increase the fuel
needs of a coal-fired plant with CCS by 25%-
40%.

22.  Geological storage
 Oceans as carbon sequestrators
 Mineral storage
 Forest as carbon sequestrators
 CO2 Reuse

23. Carbon emission trading
Carbon emissions trading is emissions
trading specifically for carbon dioxide
(calculated in tonnes of carbon dioxide)
It is one of the ways countries can meet their
obligations under the Kyoto Protocol to
reduce carbon emissions and thereby
mitigate global warming

24. A central authority (usually a government or
international body) sets a limit or cap on the
amount of a pollutant that can be emitted
Companies or other groups are issued emission
permits and are required to hold an equivalent
number of allowances (or credits) which represent
the right to emit a specific amount
The total amount of allowances or credits cannot
exceed the cap, limiting total emissions to that
level.

25. Companies that need to increase their emissions
must buy credits from those who pollute less.
The transfer of allowances is referred to as a
trade.
In effect, the buyer is paying a charge for
polluting, while the seller is being rewarded for
having reduced emissions by more than was
needed.

26. Kyoto Protocol and Carbon Trading
 The Kyoto Protocol is a 1997 international
treaty which came into force in 2005, which
binds most developed nations to a cap and
trade system for the six major greenhouse
gases.[13]
 (The United States is the only industrialized
nation which has not ratified and therefore is
not bound by it.)
 Emission quotas were agreed by each
participating country, with the intention of
reducing their overall emissions by 5.2% of
their 1990 levels by the end of 2012.

27.  Under the treaty, for the 5-year compliance
period from 2008 until 2012, nations that emit
less than their quota will be able to sell
emissions credits to nations that exceed their
quota.
 It is also possible for developed countries
within the trading scheme to sponsor carbon
projects that provide a reduction in greenhouse
gas emissions in other countries, as a way of
generating tradeable carbon credits.

28. The Protocol allows this through Clean
Development Mechanism (CDM) and Joint
Implementation (JI) projects, in order to
provide flexible mechanisms to aid regulated
entities in meeting their compliance with their
caps.

29. What is CASMGS?
 A team of scientists at 10 universities and
government laboratories form the Consortium for
Agricultural Soils Mitigation of Greenhouse
Gases.
 With federal funding, this group will provide the
science and technology necessary to help our
nation realize the benefit of carbon sequestration.
 CASMGS brings together the nation’s top
researchers in the areas of soil carbon,
greenhouse gas emission, conservation
practices, computer modeling and economic
analysis.

30. WHAT CAN AGRICULTURAL PRODUCERS
DO TO ENHANCE CARBON
SEQUESTRATION?
a. No-till or reduced-till
b. Increased crop rotation intensity by eliminating
summer fallow
c. Buffer strips
d. Conservation measures that reduce soil erosion
e. Using higher residue crops, such as corn, grain
sorghum and wheat
f. Using cover crops
g. Selecting for varieties and hybrids that store more
carbon