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AGROFORESTRY AND WOODFUEL PRODUCTION: SOME DATA FROM AGROFORESTRY SYSTEMS IN AFRICA

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AGROFORESTRY AND WOODFUEL PRODUCTION:

SOME DATA FROM AGROFORESTRY SYSTEMS IN AFRICA

.

Results

In addition to traditional studies of AFS, which often

focus on their agricultural and pastoral productivity or

their environmental services, it would be desirable to

launch more research on their wood energy

productivity.

This would help to better understand the interests of

farmers, devise more productive and profitable

systems, and orientate the energy policies of the South.

This research may also inspire scientists working in the

North, where the use of wood energy is becoming

increasingly topical and where data on the wood

energy production of agroforestry systems are very

rare.

Conclusion

Régis PELTIER

1

References

3

Centre International de Recherche Agronomique pour le Développement

CIRAD-ES-UR-BSEF), Montpellier, France (

peltier@cirad.fr

)

Introduction

Discussion

This set of data on the

productivity of AFS is a first

step forward.

The data clearly show the

socio-economic importance of

these systems for the supply of

wood energy to African

populations.

However, precise production

figures remain elusive as

studies have been carried out

either on small plots or over

large surface areas on the

basis of limited inventories.

Material and methods

In the past, fuelwood production played an important economic role in European

agroforestry systems (AFS), as was the case in the Cevennes in southern

France. Wood pruned or pollarded from chestnut, ash and fruit trees was used for

heating and cooking. Very little data have been published on the quantities of wood

that were produced, but p.c. indicate values of about 2.4 t/ha/year.

In many African countries, farmers harvest most of their fuelwood in their own fields

and pastures. Yet although numerous studies have been conducted, few figures

have been published about the actual productivity of African AFS.

.

With the support of WB, AFD and FFEM, projects are developing wood energy

master plans to supply African cities. Researchers are being asked to provide figures

to estimate fuelwood production in the anthropized areas which cover most of these

cities’ supply basins. CIRAD and its partners have conducted a number of studies

that provide an initial assessment of the productivity of AFS in Africa.

.

Agroforestry systems

in St-Pons, West Cevennes,

Southern France

Faidherbia albida parkland

in Sirlawe,

North Cameroon

Logging a plantation of

Acacia senegal to produce

fuelwood before planting

corn, North Cameroon

Wood harvested in a fallow

enriched by planting

A. auriculiformis, conditioned

for making charcoal,

D.R.Congo

Harsh pollarding of Faidherbia albida

due to lack of fuelwood,

North Cameroon

Regrowth of young

branches on a Faidherbia

one year

after pollarding

Bisiaux F, Peltier R, Muliele J-P ( 2009) Plantations industrielles et agroforesterie au service des populations des plateaux Batéké, Mampu, en République démocratique du Congo. Bois et Forêts des Tropiques 301 (3): 21-31. CIRAD, IDA, BEIE, CTFC (2015) Schéma Directeur d’Approvisionnement en Combustibles Domestiques de Maradi et Zinder. Technical document . Banque Mondiale, Washington, USA.

D’Andous Kissi O, Guibert H, Palou Madi O,Ntoupka M, Deleporte P, Smektala G, Peltier R ( 2013) Le bois, un atout pour la diffusion des plantations d’acacias gommiers au nord du Cameroun. Revue Française Forestière (2013)3 : 241-253.

Harmand J.M, Njiti FC, Bernhard-Reversat F, Puig H (2004) Aboveground and belowground biomass, productivity and nutrient accumulation in tree improved fallows in the dry tropics of Cameroon. Forest Ecology and Management, 188 (1-3): 249-265.

Peltier R, Njiti Forkong C, Ntoupka M, Manlay R, Henry M, Morillon V (2007) Evaluation du stock de carbone et de la productivité en bois d'un parc à karité du Nord-Cameroun. Bois et Forêts des Tropiques 294 (4): 39-50.

Smektala G, Peltier R, Sibelet N, Leroy M, Manlay R, Njiti C F, Ntoupka M, Njiemoun A, Palou O, Tapsou (2005) Parcs Agroforestiers Sahéliens : de la conservation à l'aménagement. Revue électronique VertigO, Institut des Sciences de l’Environnement, Université du Québec, Montréal, Canada, vol 6, n° 2.

In many African countries, CIRAD has helped introduce an innovation which involves

planting fallow land with leguminous trees to improve slash-and-burn systems,

restoring the fertility of degraded land and limiting forest clearing by farmers while

increasing the production of wood energy.

In northern Cameroon, traditional agroforestry systems have been renovated through

Assisted Natural Regeneration (ANR). To enable diverse productions (tree fodder,

fuelwood, shea fruit, and Faidherbia pods) while limiting shade over crops, livestock

owners and tree owners came to an agreement that pollarding would take place on a

rotating basis every eight years.

CIRAD, IRAD and AgroParisTech have studied the fuelwood productivity of these AFS.

Logging planted tree fallows

In Ngong (northern Cameroon), fallow was improved by planting Acacia senegal on ferruginous alluvial soils with 900

mm/year of rainfall. At the end of 15 years, the production of wood energy was 2.74 t/ha/year (

€73/ha/year).

In Mampu, Bateke plateau (DR Congo), fallow was improved by planting Acacia auriculiformis on thick sandy soils,

with 1,400 mm/year of rainfall. The average production of wood energy was 10 t/ha/year.

Pollarding Sahelian and Sudanese agroforestry parklands

• Calculations on small plots (in northern Cameroon) with a high density of trees

 Near Ngong (see above), shea tree (Vitellaria paradoxa) parkland pruning is done late in the dry season to

provide supplementary food for cattle and reduce shade on crops. For a density of 30 adult trees/ha, the fuelwood

productivity has been estimated at 1.07 t/ha/year.

 A large Faidherbia albida parkland is located to the east of the city of Maroua. The soils are alluvial and

ferruginous, rainfall is 600 mm/year. Trees which retain their foliage throughout the dry season are pollarded to

provide a nutritional supplement for livestock. For a density of 30 mature trees/ha, fuelwood production was

estimated at 3 t/ha/year.

• Calculations on very large areas (in Niger) with a low density of trees

In the fuelwood supply basin of Zinder, the surface of agroforestry areas was estimated to be 5,108,237 ha. The

calculated production of pollarded wood is 0.043 t/ha/year, i.e. at the basin scale, 217,444 t/year (sold at a retail

price of €100/t), representing 54% of the wood energy produced in the region.

Harvesting cassava grown after

fallow planted with Acacia

auriculiformis, D.R. Congo

Fuelwood produced by pollarding

in a shea tree parkland,

North Cameroon

3rd European Agroforestry Conference

23-25 May 2016,

Montpellier, France

Introduction

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