Download 2.2. Integrating climate change into forestry: Mitigation

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Narration: This presentation will introduce you to climate change and the contribution of forests
to mitigation.
This presentation will introduce you to climate change and mitigation. It will be complemented
by other presentations in Topic 4 on carbon measurement and modelling.
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Narration: Do you understand the concepts in the slide? What is the difference between
adaptation and mitigation in forestry?
In this quiz you can test yourself to see how much you have learned about the role of forests in
climate change.
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Narration: The presentation starts with a short introduction about forests and carbon at the
global scale. Then you will learn the basic concepts about carbon and ecosystems. Next, you will
learn about the forest activities that contribute to climate change mitigation. Finally, you will
learn about the why and how of carbon accounting.
The presentation starts with a short introduction about forests and carbon at the global scale.
Then you will learn the basic concepts about carbon and ecosystems. Next, you will learn about
the forest activities that contribute to climate change mitigation. Finally, you will learn about the
why and how to do carbon accounting.
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Narration: First, you will learn about the carbon cycle at the global scale before downscaling at
the forest scale. Today, the use of fossil fuel is responsible for an emission of 7.2 billion tonnes of
carbon per year, of which 4.1 accumulate in the atmosphere. The non-accumulated carbon - 2.2
billion tonnes per year - is absorbed by the oceans. However, a terrestrial sink of 1 is still missing.
Deforestation - mainly tropical - emits 1.6, this means that 2.6 tonnes of carbon per year are
absorbed by the biosphere.
First, you will learn about the carbon cycle at the global scale before downscaling at the forest
scale. All figures are in billions of tonnes of carbon per year. Today, the use of fossil fuel is
responsible for an emission of 7.2 billion tonnes of carbon per year, of which 4.1 accumulate in
the atmosphere. The non-accumulated carbon - 2.2 billion tonnes per year - is absorbed by the
oceans. However, a terrestrial sink of 1 is still missing. Deforestation - mainly tropical) - emits
1.6, it means that 2.6 tonnes of carbon per year are absorbed by the biosphere. This is the result
of expanding forests in developed countries, the enhancement of ecosystem productivity by
higher atmospheric CO2 concentrations, and a longer growing season in northern latitudes.
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Narration: These are some examples of CO2 emissions from daily life.
These are some examples of CO2 emissions from daily life. In discussions about climate change
the term “footprint” is commonly used. The ecological footprint is a measure of human demand
on the Earth's ecosystems
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Narration: Today, the major sources of emissions from deforestation are located in developing
countries, especially in South Asia and Tropical America. The conversion of forests in developed
countries emitted large amounts of greenhouse gases after the Industrial Revolution. The trend is
now to increase forest cover, which contributes to the absorption of carbon.
Today, the major sources of emissions from deforestation are located in developing countries,
especially in South Asia and Tropical America. The conversion of forests in developed countries
emitted large amounts of greenhouse gases after the Industrial Revolution. The trend is now to
increase forest cover, which contributes to the absorption of carbon. This is indicated by the
green bars in the figure for North America and Europe.
Source: IPCC FAR 2007, Houghton 2003
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Narration: At the forest scale, two important concepts must be introduced: stock and flux. A
forest - or any ecosystem - is a set of carbon stocks. Carbon is everywhere, from the leaves to the
soil. A good way to visualise a stock of carbon is to think of the biomass stored in the ecosystem.
Biomass is the mass of living biological organisms in a given area or ecosystem at a given time.
Almost 50% of the dry biomass is carbon. If the dry biomass of a tree is 2 tonnes, then it contains
around 1 tonne of carbon.
At the forest scale, two important concepts must be introduced: stock and flux. A forest - or any
ecosystem - is a set of carbon stocks. Carbon is everywhere, from the leaves to the soil. A good
way to visualise a stock of carbon is to think of the biomass stored in the ecosystem. Biomass is
the mass of living biological organisms in a given area or ecosystem at a given time. Almost 50%
of the dry biomass is carbon. If the dry biomass of a tree is 2 tonnes, then it contains around 1
tonne of carbon.
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Narration: Here are some examples of carbon stocks in forests. For example, a tropical wet
forest can store up to 430 tC per hectare in the aboveground biomass.
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Narration: A forest - or any ecosystem - is a set of carbon fluxes. Using the daylight as a source
of energy, the leaves absorb carbon dioxide from the atmosphere and transform it through the
process of photosynthesis. The products of this process are distributed to the plant and move to
the litter and soil when branches or leaves fall and decompose. Other fluxes are emitting CO2
back in to the atmosphere through respiration and soil mineralisation. Products exported from
the ecosystem, such as wood, are also responsible for carbon fluxes. The important fluxes are
those between the atmosphere and the biosphere.
The second important concept is flux. A forest - or any ecosystem - is a set of carbon fluxes.
Using the daylight as a source of energy, the leaves absorb carbon dioxide (CO2) from the
atmosphere and transform it through the process of photosynthesis. The products of this
process are distributed to the plant and move to the litter and soil when branches or leaves fall
down and decompose. Other fluxes are emitting CO2 back in to the atmosphere through
respiration and soil mineralisation. Products exported from the ecosystem, such as wood, are
also responsible for carbon fluxes. The important fluxes are those between the atmosphere and
the biosphere. The difference between inbound (photosynthesis) and outbound fluxes
(respiration and mineralisation) is the net absorption flux.
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Narration: Here is an example of measurement of carbon flux within an ecosystem and between
the ecosystem and the atmosphere. The important flux for those interested in climate change is
the resulting flux of the exchanges between the atmosphere and the biosphere. In this example,
the forest removes 5.9 tonnes of carbon per year per hectare from the atmosphere.
On the left, there is an example of measurement of carbon flux within an ecosystem and
between the ecosystem and the atmosphere. The important flux for those interested in climate
change is the resulting flux of the exchanges between the atmosphere and the biosphere,
indicated in the diagram on the right. In this example, the forest removes 5.9 tonnes of carbon
per year per hectare from the atmosphere.
Source: IPCC, 2000
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Narration: The two concepts of stock and flux are directly linked. If the stock increases, it means
that the ecosystem absorbs more carbon. This is due to the Law of Conservation of Mass. For
example, if your bank account is growing, it means there is more money entering than going out.
In a growing ecosystem, the net balance of flux is an inbound flux. This means that CO2 is
removed from the atmosphere, the atmospheric concentration of greenhouse gases is decreased
and climate change is reduced. This process is called carbon fixation, absorption or removal and
the ecosystem is called a carbon sink.
The two concepts of stock and flux are directly linked. If the stock increases, it means that the
ecosystem absorbs more carbon. This is due to the Law of Conservation of Mass. For example, if
your bank account is growing, it means there is more money entering than going out. In the a
growing ecosystem, the net balance of flux is an inbound flux. It means that CO2 is removed
from the atmosphere, the atmospheric concentration of greenhouse gases is decreased and
climate change is reduced. This process is called carbon fixation, absorption or removal and the
ecosystem is called a carbon sink.
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Narration: If the stock decreases - for instance in a decaying or burning forest - an outbound flux
will increase the atmospheric concentration of greenhouse gases and increase climate change.
The process is called carbon emission and the ecosystem is called a carbon source.
If the stock decreases - for instance in a decaying or burning forest - an outbound flux will
increase the atmospheric concentration of greenhouse gases and increase climate change. The
process is called carbon emission and the ecosystem is called a carbon source.
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Narration: If we measure a carbon stock of 30 tonnes of carbon at a given time and a stock of
135 tonnes of carbon after 7 years, it means that, on average, the ecosystem has removed or
absorbed 15 tonnes of carbon per hectare per year from the atmosphere.
If we measure a carbon stock of 30 tonnes of carbon per hectare at a given time and a stock of
135 tonnes of carbon per hectare after 7 years, it means that, on average, the ecosystem has
removed or absorbed 15 tonnes of carbon per hectare per hectare and per year from the
atmosphere.
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Narration: After these basic definitions of stocks and fluxes, you can imagine the
evolution of carbon stock under different management. Charts 1 to 6 represent the
evolution of aboveground carbon stocks in different ecosystems. Match each carbon
stock graph with its description to the right. Then share your answers.
Quiz answers:
First, the most simple ones. Non-forested land has constant levels of low carbon
content: 6.
Conserved primary forest has constant levels of high carbon content: 2.
When forest is converted to non-forested land use the carbon content abruptly changes,
from high carbon content before the conversion to low carbon content after: 5.
When a forest is converted to a plantation, the high carbon content before the
conversion abruptly drops then builds up again: 3. (Note that the carbon content at the
end could be higher or lower than the level before conversion)
Plantation established on non-forested land and harvested regularly has low carbon
content at the beginning then cycles: 1.
Unsustainably managed forest begins with high carbon content that gradually decreases:
4.
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Narration: In this example, there is a degraded pasture (A), with a low and constant
carbon stock. (B) is a forest plantation, even destroyed or burnt regularly. The
comparison of carbon stocks under the two scenarios shows that there is more carbon in
(B). The difference with (A) is the amount of carbon that does not contribute to climate
change if we choose to create a plantation in a degraded pasture.
To evaluate the contribution of land use to climate change mitigation, it is useful to
compare scenarios. In this example, there is a degraded pasture (A), with a low and
constant carbon stock. (B) is a forest plantation, even destroyed or burnt regularly. The
comparison of carbon stocks under the two scenarios shows that there is more carbon
in (B). The difference with (A) is the amount of carbon that does not contribute to
climate change if we choose to create a plantation in a degraded pasture. The fact that
the storage in the plantation is not permanent does not mean that there is no
contribution to climate change mitigation. A temporary storage can reduce the
concentrations of greenhouse gases during a fixed period of time.
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Narration: Undisturbed forests require special attention. A growing ecosystem is a carbon sink,
but undisturbed forests are in more or less in equilibrium, as their biomass cannot grow
indefinitely. If the carbon stock is more or less constant, the ecosystem is no longer a sink. This is
a simplified view and there many scientific debates about this issue. The future of these sinks is
also highly debated. With the impact of climate change will undisturbed forests become a
source? But even if an undisturbed forest does not contribute to absorbing greenhouse gases
from the atmosphere, it is better to conserve an undisturbed forest than to convert it to other
uses.
Undisturbed forests require special attention. A growing ecosystem is a carbon sink, but
undisturbed forests are in more or less in equilibrium, as their biomass cannot grow indefinitely.
If the carbon stock is more or less constant, the ecosystem is no longer a sink. This is a simplified
view and there many scientific debates about this issue. In fact, current flux measurements
show that undisturbed forests are sinks, mainly because of CO2 fertilisation, recuperation from
past disturbances, or problems of spatial sampling. The future of these sinks is also highly
debated. With the impact of climate change will undisturbed forests become a source?
Regardless, even if an undisturbed forest does not contribute to absorbing greenhouse gases
from the atmosphere, it is better to conserve an undisturbed forest than to convert it to other
uses.
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Narration: Primary forest usually has a larger carbon stock than a plantation. Does this
mean that a primary forest does not contribute to climate change mitigation? Would a
better option be to replace it by a growing plantation which absorbs carbon? The answer
to both of these questions is “no”. An important fact is that primary forests store a
considerable amount of carbon. Destroying them for other uses would emit a lot of CO2
into the atmosphere.
Primary forest usually has a larger carbon stock than a plantation. Does this mean that a
primary forest does not contribute to climate change mitigation? Would a better option
be to replace it by a growing plantation which absorbs carbon? The answer to both of
these questions is “no”. An important fact is that primary forests store a considerable
amount of carbon. Destroying them for other uses would emit a lot of CO2 into the
atmosphere. Comparing alternative (A), a primary forest, and (B), conversion of a
primary forest to a plantation, shows that alternative (A) would emit more carbon to
contribute to climate change.
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Narration: Forest products store carbon over a long period of time. But their main
contribution to climate change mitigation is through substitution. Forest products can
substitute for other materials such as steel or aluminium, whose production emits a
large quantities of greenhouse gases. Forest products can also substitute for other
energy sources such as oil, coal or gas. Fuelwood emits fewer greenhouse gases than
fossil fuels do, as long as the fuelwood is sustainably managed and the technology for
transforming it into energy is efficient.
Forest products can store carbon for a long time, for example in wood constructions,
but their main contribution is through substitution. Forest products can substitute for
other materials such as steel and aluminium whose production emits a lot of
greenhouse gases. Forest products can also substitute for energy, such as oil, coal and
gas.
The figure shows that the greenhouse gases balance of fuelwood is better than that of
fossil fuel, because CO2 absorption occurs when the wood is produced. However, some
conditions must be fulfilled for fuelwood to contribute to climate change mitigation.
First, the forest resource must be sustainably managed. If the forest disappears, CO2
absorption no longer exists. Second, the technology for transforming wood into energy
must be efficient.
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Narration: Many forest activities contribute to climate change mitigation. Carbon stocks can be
increased through plantations or agroforestry. Existing stocks can be conserved through reducing
deforestation. These two activities relate to carbon sequestration in the ecosystem. Emissions
caused by forest activities can be reduced, for example, by using less energy or fertilisers in forest
operations. Biomaterials and bioenergy can be produced to substitute materials or energy that
generate greenhouse gases. The last two activities refer to energy-related emissions.
Many forest activities contribute to climate change mitigation. 1. Carbon stocks can be increased
through plantations or agroforestry. The benefit of these activities is the difference between the
growing stock and the baseline, as show on the graph. 2. Existing stocks can be conserved
through reducing deforestation. In this case, the benefit of conserving is estimated with
reference to the degradation or deforestation scenario. 3. Emissions caused by forest activities
can be reduced, for example, by using less energy or fertilisers in forest operations. 4.
Biomaterials and bioenergy can be produced to substitute materials or energy that generate
greenhouse gases.
The first two activities refer to carbon sequestration in the ecosystem, while the last two refer to
energy-related emissions.
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Narration: Carbon accounting is the accounting undertaken to measure the amount of carbon
dioxide equivalents that will not be released into the atmosphere as a result of projects called
Flexible Mechanisms under the Kyoto Protocol. These projects thus include (but are not limited
to) renewable energy projects and biomass, forage and tree plantations. There are many reasons
to do carbon accounting in forestry programmes.
There are many reasons to do carbon accounting in forestry programmes. Carbon accounting is
important for demonstrating the impacts of a forestry programme on mitigation, for example
USAID-funded programmes that contribute to the Global Climate Change Earmark. It is also
important for:
•National accounting, which involves reporting on greenhouse gases and National
Communications as mandated under the Kyoto Protocol.
•Selling carbon credits for projects under the Clean Development Mechanism or voluntary
markets.
•Helping forest managers to consider carbon in their activities.
•Improving stakeholders’ understanding of the role of forests in mitigation.
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Narration: Different methods exist for carbon accounting. Onsite measurement of existing
forests can be by direct measurement. Dry matter weight and carbon content are measured for
litter or dead wood and tree destructive sampling is conducted to estimate tree biomass. Indirect
measurement can also be used, where tree diameters and heights are measured and converted
into carbon using allometric equations. Modeling approaches can be used as well as remote
sensing, which is generally combined with “ground truthing.” A simple approach is to use default
factors.
Different methods exist for carbon accounting, depending on the requirements for precision, the
available means and data, and also the status of the forestry programme under design or in
implementation. Onsite measurement of existing forests can be by direct measurement. Dry
matter weight and carbon content are measured for litter or dead wood and tree destructive
sampling is conducted to estimate tree biomass. Indirect measurement can also be used, where
tree diameters and heights are measured and converted into carbon using allometric equations.
Modeling approaches can be used for both existing or projected forest programmes. Remote
sensing is an important tool for large scale programmes or for delimitating project boundaries.
Remote sensing is generally combined with “ground truthing”. A simple approach is to use
default factors, depending on the types of ecosystem or life zones. Precision is low, but the
result is easily obtained.
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Narration: The Winrock Forest Carbon Calculator allows USAID to calculate the climate impacts
of its forestry projects worldwide in terms of reducing emissions or increasing removals of carbon
dioxide.
The Winrock Forest Carbon Calculator allows USAID to calculate the climate impacts of its
forestry projects worldwide in terms of reducing emissions or increasing removals of carbon
dioxide. Projects fall into one of five main activities:
1. Forest Protection. Project activities protect and conserve existing forest against pressure from
forest clearing (deforestation), fire, or illegal logging.
2. Forest Management. Project activities use technical forestry principles to manage and
maintain a forest for timber production while maintaining the forest’s productive and renewal
capacities. Activities might include conversion to reduced impact logging or stopping logging
activities altogether to reduce forest degradation.
3. Afforestation/Reforestation. Project activities that plant trees on land that is not currently
forested.
4. Agroforestry. Project activities establish and/or manage trees within agricultural systems
5. Changing Forest Policy. Project activities are related to forest policy changes that will
ultimately result in an improvement in the way forests are managed and harvested.
Narration: The CO2FIX model is the most widely used forest carbon simulator in the world. It was
also approved as one of the baseline methodologies for afforestation and reforestation CDM
projects. With the CO2FIX model, users can calculate the carbon balance under different landuse and forest management scenarios.
The main modules are
• above- and below-ground tree biomass,
• soil carbon,
• carbon in products, and
• carbon in bioenergy.
The above-ground biomass module has cohorts that the user defines.
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