Les mutations
du climat

L’effet de serre est produit en grande partie par l’émission de dioxyde de carbone. L’émission de dioxyde de carbone dans l’atmosphère est due à deux causes. La première provient des combustibles fossiles brûlés afin de produire de l’énergie (pétrole, charbon, gaz naturel). 
La deuxième découle de la déforestation.

Moins il y a d’arbres, moins
il y a de photosynthèse 
(un phénomène biologique où une plante absorbe 
du dioxyde de carbone). 
D’autre part, après que les arbres ont été coupés, du dioxide de carbone se forme à partir du carbone qui est dans le sol. 
(Pour en savoir davantage sur la rétention du carbone, 
clicker ici
Ce processus diminue la fertilité du sol.

Au Canada, les rejets de gaz à effet de serre se chiffrent à 21 tonnes par personne par année. Dans les pays non industrialisés, 1,85 tonnes de gaz à effet de serre sont rejetés, en moyenne, par personne par année.

Le Centre de Falls Brook, situé dans le comté de Carleton, est devenu le coordonateur du « Analog Forestry Network », une association travaillant à la restauration des forêts. 

Le « Arbofilia » au Costa Rica, « The NeoSynthesis Research Centre » au Sri Lanka, le « Rainforest Rescue » en Équateur et le « COICAP » au Pérou comptent parmi les groupes importants qui mènent des projets de reboisement.

Le type de sylviculture pratiqué par 
cette association vise à créer un écosystème forestier en fonction du maximum que pouvait soutenir, 
à l’origine, la région reboisée.



La foresterie analogue en tant que Réalisation conjointe par Ranil Senanayake

La détermination du taux de rétention du carbone par Ranil Senanayake


Analog forestry as a tool in joint implementation by Ranil Senanayake

On the setting of value for carbon sequestering by Ranil Senanayake











Other CIDA funded articles:

The Kyoto Protocol

Pedal Power in El Salvador

A Return To Diversity





















from readers,
on this article
/ Rétroaction
des lecteurs
concernant le
présent article 

Climate Change:
Different Realities North and South

Jean Arnold,
Falls Brook Centre
September 1998

t.gif (259 bytes)hese days, global warming and climate change is a hot issue. The main greenhouse gas produced as a result of human activity is carbon dioxide (CO2). Carbon dioxide is emitted when we burn fossil fuels (i.e., coal, oil and natural gas) to produce energy to power our industry, to heat and light our homes and businesses, and to fuel our vehicles. Carbon dioxide is also released to the atmosphere through deforestation.

diagram2.gif (4623 bytes)

Canadians use more energy per person than any other industrialized nation. Exhaust emissions from burning fossil fuels total about 21 tonnes of greenhouse gas per year per Canadian. By comparison, people living in non-industrialized countries emit about 1.85 tonnes of carbon dioxide per person per year.

Clearly, we in the industrialized world must address climate change. We can do this by: reducing our over-dependence on fossil fuels as an energy source; supporting energy conservation, renewable energies such as solar and wind; and the reduction of energy use.


Restoring Forests

Falls Brook Centre, a sustainable development demonstration and training centre in Carleton County, New Brunswick, has been engaged in restoration projects for the past 10 years. On-site there are tree nurseries, forest trails, heritage seed gardens, a herbarium, forest gardens and a new Acadian Forest restoration nursery. Falls Brook is the Secretariat for the Maritime Region Forest Stewardship Council.


Analog Forestry Network -
a new approach

At the international level, Falls Brook has been coordinating the Analog Forestry Network, an association of organizations working on forest restoration. Arbofilia in Costa Rica, The NeoSynthesis Research Centre in Sri Lanka, Rainforest Rescue in Ecuador and COICAP in Peru, along with other smaller community- based organizations, are part of a coalition of groups rebuilding the degraded forest lands in their area. This ecological forestry restoration program has been active for the past five years and incorporates a seed exchange between the members that offers protection from multi-national patenting efforts.

jean2.jpg (5939 bytes)
(photo: Falls Brook Centre)


Canadian host - 
J. Arnold, 
Falls Brook Centre


Southern Realities

In the non-industrialized world, tropical deforestation is being driven by several factors: greed, poverty and industrialization. Alongside fossil fuel reduction, reforestation can counter-balance some atmospheric emissions by fixation of carbon dioxide. As long as terrestrial plants are growing, their rate of uptake of CO2 through photosynthesis is greater than their release of that gas, and the net effect is a reduction of CO2 in the atmosphere.


How Forests Regulate Carbon

Forests and wetlands are natural reservoirs for storing the earth's supply of carbon. At times, these reservoirs act as "sinks", absorbing more carbon than they release; at other times they become "sources", releasing more carbon than they absorb. On average, natural cycling processes are believed to have removed as much carbon as they have added, thus keeping greenhouse heating in check.


diagram1.gif (5645 bytes)

The concern among scientists is that human activities have raised the concentration of greenhouse gases in the atmosphere, thereby trapping additional heat. Deforestation has a double effect: shifting carbon contained in trees to the atmosphere, while also reducing the number of trees that remove carbon dioxide from the air. Due to the cutting of forests, the opening of the earth for agriculture and the burning of fossil fuels, we are adding more carbon into the atmosphere than ever before.

As the temperature rises, the climate changes. Hurricanes and storms become more intense than before. Normal long-term events come more often and last for longer periods of time (for example, El Nino). Rains come at different times, so farmers find it harder and more difficult to rely on regular rainfall. Now that it is affecting farming in the North, people are beginning to pay attention.


Foster biodiversity and support human needs

Analog Forestry is a system of silviculture that seeks to establish a tree-dominated ecosystem similar in function to the original climax forest and vegetation of a region. The tree and plant species act in an analogous fashion to the original natural structure and function of the forest while also being useful to humans as crop plants. It seeks to empower rural communities, both socially and economically, through the use of species that provide marketable products. It provides specialized products of high value and products that can be processed at the community level, as well as providing the highest carbon sequestering value of any silviculture crop.

Analog Forest

jean3.jpg (7770 bytes)
(photo: Falls Brook Centre)

Analog forestry addresses biodiversity, sustainability, traditional uses, medicine, soil conservation, watershed management, and the ecological functions of tree species. Because Analog Forestry has a high potential for carbon sequestration, it enables rural communities to engage in the current discussions around climate change. (Analog forestry as a tool in joint implementation by Ranil Senanayake)


Northern Problems
Move South

Currently being discussed at the global level is Joint Implementation (JI) This means that one country can approach another country and pay them to plant trees to offset the first country's polluting emissions. At this point in time the tree planting efforts are monocultural, i.e. planting only one tree species, mostly pine and eucalyptus. Pine and eucalyptus are short term tree crops with a 25-30 rotation that do not fix much carbon in the soil.

In short-term plantations, carbon gets fixed for 30 years, is released and lost to the atmosphere in about 60 years. Then it is fixed again in the next rotation. This rotational pattern is valid only if land remains productive. If we had 90 year rotations - carbon would be fixed for 90 years and would be less labourious. Analog Forestry designs its landscape for a long term rotation of 90-100 years. (On the setting of value for carbon sequestering by Ranil Senanayake)

diagram3.gif (3599 bytes)


Carbon Improves
Soil Fertility

Another key aspect is soil. When trees are removed from a landscape, the carbon component oxidizes and turns into carbon dioxide, and the soil gets thinner and thinner. When carbon is oxidized, acidity forms. The carbon - nitrogen ratio means the more carbon there is, the more nitrogen that can be held. Carbon holds on to nitrogen (compost, manure) When nitrogen enters the soil, carbon fixes the nitrogen and holds on to it for a long time. If there is a lack of carbon content, the soil will use up the nitrogen very quickly. All farmers need nitrogen and maintaining carbon is important.

diagram5.gif (3828 bytes)

The soils' carbon pool is stored in three stages. Long-term forests are the most efficient storage. In natural forests, carbon is stored in the soil horizon by decantation and microbial action to form long-age molecules. When we cut a native forest and change to an agricultural or plantation system, the relationship is reversed. With agricultural land or short-term crop rotation, carbon is held for a short time only.

diagram4.gif (4925 bytes)

Thus to gain maximum advantage of the soil, carbon pool plantations should be similar or analogous to the natural system as natural forests sequester carbon for the longest time. In Analog Forestry, which mimics the structure and species of the natural forest, long-term pools are created as the soil matures.

jean1.jpg (6429 bytes)
(photo: Falls Brook Centre)

Bandaraela Valley -
UVA region Neo-Synthsis Research Centre

Currently, world thinking is still dominated by the monocultural phase. However we must ensure that these scientific facts are included in global planning because it allows small farmers to count their analog forest area as a component of carbon sequestering. The Falls Brook Centre works with the Analog Forestry Network members to help prepare them for the global credit trading that will undoubtedly occur. This trading will only be a poor substitute for requiring Northern polluting companies to "Clean Up Their Act."


"Produced with the support of the Canadian International Development Agency (CIDA)";
«Produit en collaboration avec l'Agence canadienne de développement international (ACDI)»