Regional Initiative for Dryland Management in Tunisia

Amel Jrad, International Center for Agricultural Research in the Dry Areas And Ms. Hela Gueliss

WATERSHED MANAGEMENT AND VEGETATIVE COVER

Background

The forests of Tunisia represent a national heritage for every citizen of the country. In many cases the forests have been lost, harming the forest's natural resources, including wildlife, under story vegetation, soils and rainfall that once infiltrated and fed the water table through the hydrological cycle. Forest conservation and development is therefore linked to the broader quality of life and the ability to extract an economic return from the land for thousands of communities. As the country loses the very ecosystems that sustain rural life, there is a slow change taking place which puts the responsibility of forestry and land management into the hands of the communities (the forestry population is estimated at 900.000 persons).


In Tunisia, there are about 10.600.000 hectares (ha) of arid and semi-arid lands affected by desertification. This represents about 65 % of the total country surface area. In the south, almost all lands are being desertified. The desertification process is induced by the retrogression of vegetation cover which is in turn is caused by an over use of natural rangelands and an irrational utilization of agricultural lands. Furthermore, the marginal physiographic conditions, unfavorable hydrological and climatological patterns, as well as socio-economic factors affecting these lands also contribute towards their degradation and ultimately their loss. This is especially true for those lands receiving less than 200 mm annual rainfall which are jeopardized by increasing erosion which leads to lower soil fertility.


Since 1990, the government of Tunisia has undertaken an ambitious program in reforestation and combating desertification which consists of:

  • Reforestation of 280.000 ha.

  • Establishment of 40.000 ha of forestry belts, wind brakes, road plantations, and biological sand dune fixation.

  • Planting 580.000 ha of fodder shrubs.

  • Management of 1 million ha of rangeland (private and collective land).

  • Construction of 4.000 km of artificial dunes.

  • Heightening of 8.000 km of artificial dunes.

The results to date are not particularly positive. It will be necessary to engage the rural communities in holistic pilot projects to demonstrate the value of joint action. Ten pilot projects have been under taken since 1995 in the north, west and central part of the country with the collaboration of the World Bank. Menzel El Habib is the only project in the south undertaken since 1997 to control natural resources degradation and lands the pilot effort in Gabes governorate in south east Tunisia. This area covers approximately 120.000 ha forest of desertified plateau and coastal plain. The average annual rainfall is estimated at 80 - 100 mm.



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Agricultural Water Management: Proceedings of a Workshop in Tunisia Regional Initiative for Dryland Management in Tunisia Amel Jrad, International Center for Agricultural Research in the Dry Areas And Ms. Hela Gueliss WATERSHED MANAGEMENT AND VEGETATIVE COVER Background The forests of Tunisia represent a national heritage for every citizen of the country. In many cases the forests have been lost, harming the forest's natural resources, including wildlife, under story vegetation, soils and rainfall that once infiltrated and fed the water table through the hydrological cycle. Forest conservation and development is therefore linked to the broader quality of life and the ability to extract an economic return from the land for thousands of communities. As the country loses the very ecosystems that sustain rural life, there is a slow change taking place which puts the responsibility of forestry and land management into the hands of the communities (the forestry population is estimated at 900.000 persons). In Tunisia, there are about 10.600.000 hectares (ha) of arid and semi-arid lands affected by desertification. This represents about 65 % of the total country surface area. In the south, almost all lands are being desertified. The desertification process is induced by the retrogression of vegetation cover which is in turn is caused by an over use of natural rangelands and an irrational utilization of agricultural lands. Furthermore, the marginal physiographic conditions, unfavorable hydrological and climatological patterns, as well as socio-economic factors affecting these lands also contribute towards their degradation and ultimately their loss. This is especially true for those lands receiving less than 200 mm annual rainfall which are jeopardized by increasing erosion which leads to lower soil fertility. Since 1990, the government of Tunisia has undertaken an ambitious program in reforestation and combating desertification which consists of: Reforestation of 280.000 ha. Establishment of 40.000 ha of forestry belts, wind brakes, road plantations, and biological sand dune fixation. Planting 580.000 ha of fodder shrubs. Management of 1 million ha of rangeland (private and collective land). Construction of 4.000 km of artificial dunes. Heightening of 8.000 km of artificial dunes. The results to date are not particularly positive. It will be necessary to engage the rural communities in holistic pilot projects to demonstrate the value of joint action. Ten pilot projects have been under taken since 1995 in the north, west and central part of the country with the collaboration of the World Bank. Menzel El Habib is the only project in the south undertaken since 1997 to control natural resources degradation and lands the pilot effort in Gabes governorate in south east Tunisia. This area covers approximately 120.000 ha forest of desertified plateau and coastal plain. The average annual rainfall is estimated at 80 - 100 mm.

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Agricultural Water Management: Proceedings of a Workshop in Tunisia The population is estimated about 13.000 and is mostly involved in livestock production of some 50.000 heads of sheep and goat. In the late 1980’s, government protection programs were intensified in this area to address the movement of sand dunes and the need to provide alternatives for pastoral communities. In spite of this effort, better techniques and strengthened community involvement are necessary to make programs successful. Main objectives of the project are the following: Infrastructure and agricultural land protection against sand erosion. Rangeland development and livestock protection Soil and water conservation Improvement of rural population sources of revenues and combating rural exodus. Main Accomplishments: Seed collection and inventory of indigenous and exotic adapted species in the region. Nursery work : Nursery bud preparation. Techniques of seeding production. Local and exotic species grown and offered to farmers and organizations Plantation in Menzel Habib (Henchir Snoussi) Indigenous species (14) Exotic species (2) were planted for multiple uses and for combating desertification with community participatory approach. Rangeland management: target species were planted for rangeland improvement with the collaboration of the forestry department of Gabes. Continuing activities: Create an inventory of indigenous and cultivated species and collect genetic materials Procure a drier and treatment unit for vegetative material. Improve strategies for conservation of target species. Elaborate and publish a guide for rational rangeland use. Train farmers in rangeland management. Install plant nurseries on local farms. Regional exchanges Treated Wastewater and Biosolids reuse Project Description Tunisian arid regions cover more than 75% of the country’s area. In these regions, the average annual precipitation ranges between 100 and 350 mm/year, with 90% of this area receiving less than 200 mm/year. With the awareness of limited water resources in the arid Tunisian zone, the Ministry of Agriculture has undertaken great efforts to mobilize available run-off by watershed management. However, the limited quantities of runoff and its high sediment and salt concentration and the high evaporation rates make it difficult to manage this water resource at a

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Agricultural Water Management: Proceedings of a Workshop in Tunisia large scale. Therefore, fossil ground water is still the most significant water resource supply for all economic activities requiring water. Tunisian water planners are continually searching for additional sources of water that can be used economically and effectively to promote further development. In order to alleviate the problem of fresh water scarcity, the government has adapted a policy calling for the reuse of treated wastewater. Tunisia has extensive experience in the area of wastewater reuse in irrigation of agronomic crops and green areas. Treated wastewater has been reused to irrigate the Soukra agricultural area (600 ha: citrus and olive trees orchards) since the early 1960s. Currently, secondary level wastewater effluent is used to irrigate about 6.000 ha of orchards, forage crops, cotton, cereals and golf courses. The total area with reclaimed wastewater is projected to be 22.000 ha during the next decade. Considerable research has been undertaken to study various aspects of agricultural reuse, showing that treated wastewater irrigation produced higher yields than groundwater irrigation. Studies of contamination of crops and groundwater, when treated wastewater is used, revealed little significant impact on soils, crops or groundwater. Both opportunities and problems exist in using treated wastewater and biosolids. Problems are not only due to the quality of water and biosolids or standards adapted but also due to climate, soil types, choice of crops, agricultural and land use practices and farmers and public attitudes. The objectives of our project are: To utilize treated wastewater and biosolids under controlled conditions which ensure minimum health risks to human and environment. To identify economic crop varieties that present the optimum mix of income and public safety. To study public acceptance attitudes of wastewater and biosolids reuse for agricultural purposes in arid areas of Tunisia. To study socioeconomic impacts of the reuse. Main Accomplishments Achievement of a complementary treatment station using infiltration percolation: Realization of the civil engineering works and installation of three pumping stations with 10l/s capacity/station. Realization of the civil genius works of the infiltration percolation station and the installation of a pivot. Construction of a tank for the treated waste water with a capacity of 100 m3. Realization of electric equipment. The cost of the pilot is about 158147, 120DT. Monitoring of treated wastewater quality from Gabes’ treatment plant. Monitoring of complementary treated wastewater quality from the pilot unit of complementary treatment by infiltration percolation in Gabes’ treatment plant. See tables. Adoption of the standard of the biosolids reuse by legislative instance in Tunisia.

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Agricultural Water Management: Proceedings of a Workshop in Tunisia Participation of members from initiative in the regional technical workshop related to TWW and Biosolids in Granada. TUNISIAN ACTION PLAN (JULY 2003-JUNE 2005) Component I: Principal objective work is the Watershed management Initiative site for phase II Menzel Habib, located in the Gabes Governorate of southeast Tunisia, was selected as a site where a holistic and integrated approach could be implemented through pilot projects. The area of the pilot zone covers approximately 100.000 ha in the form of mountain foothills that give way to plateau and costal plain (Menzel el Habib), and has a population of 12.000. Project objectives Establish a regional plan for forestry development in the arid zones, which takes into account research, extension and dispersal/collection of necessary information to plan, manage and reforest the pilot zone. Regenerate degraded lands by introducing well-adapted forest species while linking the forest activity to a simultaneous provision of forage resources as a means of compensation for “lost” grazing. Protect infrastructure developments in the pilot zone from sand dune formation (roads, villages, agricultural perimeters). Conserve water and soil through targeted actions on specific sites that stop soil erosion and maximize water recharge by the use of bands, dams, dikes, ridges, pits and other forms of water harvesting Contribute to a community action plan, which adopts conservation or rehabilitation of critical areas of forest and provides a system of management that permits the use of these areas to be flexible and exploitable but also renewable as a source of woods and a feed resource during times of drought. Activities In Menzel Habib, the main activity is the incorporation of indigenous knowledge and local germplasm to meet soil conservation and land stabilization. The socio-economic purposes could come from exchange of materials knowledge, experience and genetic resources in the area of plant adaptation, selection, propagation and delivery to rural communities. (See table) Component II: Principal objective work is the TWW and Biosolids Management Both opportunities and problems exist in using treated wastewater and biosolids. Problems are not only due to quality of water and biosolids or standards adapted but also due to climate, soil types, choice of crops, agricultural and land use practices and farmers and public attitudes.

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Agricultural Water Management: Proceedings of a Workshop in Tunisia Project objectives To utilize treated wastewater and biosolids under controlled conditions which ensure minimum health risks to human and environment. To identify economic crop varieties that present the optimum mix of income and public safety To study public acceptance attitudes of wastewater and biosolids reuse for agricultural purposes in arid area of Tunisia. To study socioeconomic impacts of the reuse.

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Agricultural Water Management: Proceedings of a Workshop in Tunisia THE NATIONAL ACADEMIES Advisers to the Nation on Science, Engineering, and Medicine APPENDIXES