It is also prey to deep socio-economic changes. This situation raises the major challenge of ensuring the balance between protection of the various ecosystems and the development of rural populations who live in them. Increasing economic diversification, accelerated and amplified in the context of rural policy reform and globalization of trade, has contributed to an intensification of desertification processes, in spite of the efforts nevertheless exerted by government organizations.
In order better to understand the processes involved in changes taking place in Jeffara and identify the limits beyond which the pressure of human activity causes an irreversible depletion of natural resources, a multidisciplinary research programme was set up in 2000 by the IRD, working in conjunction with local partners, over a study area of about 120 000 hectares (1). The approach adopted laid emphasis on the study of the interrelations between changes among local actors and their activities, on the one hand, and those of the environments, on the other. This revealed the issues, the assets and risks involved, as well as the conflicts that arise for the use of rare and fragile natural resources. The analysis results were used as a basis for recommendations drawn up to foster improved harmonization between desertification control strategies and the legitimate socio-economic development of local communities.
The rural populations of Jeffara have always known how to adapt themselves to the region’s restrictive environmental conditions by developing original practices in the use of resources and by adopting diversified family-based strategies (multi-activity based way of life, migration and so on). However, these old, traditional ways of regulating resource use are now being called into question. For 40 years now, pressure on resources has strongly increased, especially on water stocks. The pattern has changed, from concentrated production on small areas alongside extensive livestock rearing over much larger areas, to the development of several economic activities at once that depend on the same catchment areas. The same groundwater thus feeds drinking water supply, tourism, irrigation of large plantation plots (olive groves) and the food industry. In response to this pressure, systems to foster rain water and run-off water recovery have long been operating involving jessour (2) or, more recently, water and soil conservation schemes. The latter, set up along the main run-off pathways and their tributaries, slow down the run-off speed, thus favouring infiltration and recharging of the water tables.
In the Jeffara, the crop plantations established on weakened soils are increasingly fragmenting the land space. Such land is now reaching saturation level and soil degradation has intensified. Between 1974 and 1999, the areas cultivated increased by 180% in the mountains, 356% on the piedmonts and 798% on the central plain. This intensification of agricultural land uses stems partly from a State policy which since the 1960s has been resolutely in favour of land privatization, and has generated a “land rush”. Arboriculture has therefore developed at the expense of livestock farming in the piedmonts and the plains, even on land where the terrain is unsuitable. This trend is a threat to a number of ecosystems which indeed are in danger of disappearing. Ecological studies reveal, in addition to the disturbing erosion of original vegetation assemblages, an increasing overall uniformity of the flora and hence a loss of biodiversity.
Such degradation can be checked by prohibiting the development of endangered natural environments for cultivation. However, real practical alternatives must in that case be proposed to farmers, in the agriculture sector, through maintenance of a certain diversified production in their holdings and enhancing commercial value of high-quality local or regional produce, but also by means of diversification of activities and of sources of revenue other than farming. This diversification would offer people improved flexibility to face up to climatic and economic hazards and enable them to manage better their families’ financial resources. In addition, the effort government has made in water management, through the CES, could be enhanced by schemes for desalinating brackish water and recycling waste water.
In the Jeffara, desertification control and socio-economic development do appear to be reconcilable, on condition that the specific nature of each environment and the social dynamics that make it up are taken as a whole, with a long-term viewpoint, incorporating economic and social contexts going beyond the regional territory. This issue is crucial for the future of the local people, who would no longer be obliged to leave their region in search of better standards of living.
Following this study, the Jeffara region became one of the pilot sites in Tunisia for the ‘Réseau des Observatoires de Suivi des Ecosystèmes à Long Terme’ (ROSELT) promoted by the Observatoire du Sahel et du Sahara (OSS) in which the IRD is involved.
(2) Local name for the small traditional dams emplaced in ravines and encased valleys for upstream collection of water and the soil that it carries.
Marie Guillaume | alfa
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