CDM: a tool for development. The Keita case

The Sahelian environment is characterised by high degradation of soil resources due to overexploitation. This condition produces negative impacts on sustainable development as it favours desertification and reduces food crops production. As consequence the populations are exposed to a continuous risk of food crisis. Sahelian soils must be managed in order to enable the nutritional capacity reconstitution and combat degradation.
In this environment Acacia Senegal can have various effects:
- reducing and stopping desertification process thanks to the control of the erosion, sand dune fixation and soil nutrients enrichment.
- providing local populations with an additional source of income, as Acacia Senegal produce arabic gum “gommerais”.
- awakening rural populations to a sustainable use of natural resources.

ACACIA SENEGAL (Acacia Senegal (L.) Willd.) finds its ideal habitat in arid zones with annual rainfall of 250-500 mm and can stand a period of drought of 8 up to 11 months. Ideal temperatures are between 20 and 35°C. It prefers sandy soils or light loam soils.
The production of high quality arabic gum, highly appreciated in the market, can be exploited since the fourth-fifth year after planting for, at least, 15 years, the average production can be estimated at 250 gr./plant

Considering that the current situation of the world market is favourable to arabic gum marketing and that a remarkable number of sahelian rural actors consider arabic gum as a resource able to provide additional income, it is possible to recommend the introduction of Acacia Senegal into the rural system allowing, at the same time, the supply of arabic gum, forage, and soil fertility.
To date, afforestation with acacia was difficult to realize, if not included in a political context assigning funds for sustainable development and natural resources conservation in the framework of combat desertification. Today, the introduction of Clean Development Mechanism (CDM) represents a new alternative. The use of “gommerais” as trees species for CDM’s interventions has been widely encouraged by SBSTTA of UNCBD (Montreal, November 2001).

THE PRESENT world market demand for arabic gum is near to 45.000 Tons and has increased by 40% in the latest 9 years. Gum arabic is the only Sahelian agro-forest product marketed at the international level.
With its production of about 1.000 T/year, Niger is a small producer. Niger agro-climatic conditions are particularly suitable for growing Acacia senegal, therefore production might be increased through investments in the framework of forestations with this species

Keita site: a case study for CDM

The Keita site characteristics in terms of technical experiences, available information and specific studies make it an ideal test site to evaluate the afforestation intervention efficiency in the CDM’s perspective.

The environmental impacts has been evaluated in relation to the objectives of:
UNCCD
- reduction of erosion phenomena through the increase of water infiltration and reduction of surface runoff
- increase of soil fertility through the deposit of organic materials and fixation of nitrogen
- control and reversal of the desertification process
- recovery and improvement of soils
UNFCCC and Kyoto Protocol
- contribution to atmospheric CO2 storage through the establishment of a “carbon sink”
- conservation of soil carbon reducing mineralization processes
UNCBD
- promote the establishment of a new biodiversity through the development of a favourable environment for the re-colonisation and development of flora and fauna.

As concerns the estimation of atmospheric carbon sequestration, the analysis has been done using: i) the data obtained from soil samples, ii) the monitoring of plantations, and iii) the specific analyses - both dendrometric and of amount of carbon sequestered - obtained from the chronosequences of the afforestations implemented in the area between 1984 and 2002

Local rural system information allowed the evaluation of the impact of Acacia Senegal afforestation on the local socio-economic aspects. Keita population is exposed to recurrent food crises determined by insufficient or badly distributed rainfalls and confronts chronic poverty. Acacia Senegal, successfully experimented in the area in the framework of soil conservation and rehabilitation, could supply an additional source of income to the local populations and contribute to combat poverty through the production of arabic gum.

The remarkable socio-economic actions are:
- creation of an institutional and operational framework assuring the rural system management within sustainable development objectives and combating poverty;
- organisation of local population in co-operatives assuring the plantation and tree nurseries management, conservation and sustainability and specialised in arabic gum exploitation;
- assure an income to local population from the marketing of arabic gum

In conclusion, the Keita site is a unique example that might provide information on the various typologies and degrees of impacts that afforestation actions can have at the local and global level, and, for this reason it can be considered an operational reference for the identification and definition of CDM initiatives in the Sahelian area.