Academic journal article Agricultural and Resource Economics Review

A Stochastic Frontier Approach for Measuring Technical Efficiencies of Date Farms in Southern Tunisia

Academic journal article Agricultural and Resource Economics Review

A Stochastic Frontier Approach for Measuring Technical Efficiencies of Date Farms in Southern Tunisia

Article excerpt

The main objective of this research is to compare estimates of technical efficiency obtained from the stochastic frontier approach for two samples of farmers of private and water user associations in the Nefzaoua Oases region (Tunisia), which are characterized by a severe scarcity of water and especially a high degree of salinity. Technical inefficiency effects are modeled as a function of farm-specific socioeconomic factors. Results suggest that both systems are technically inefficient. On average, the private system is found to be slightly more efficient than the associative one. Date yield could be explained mainly by four variables: water quantity applied per palm tree, labor per palm tree, phosphate per palm tree, and water salinity. Output elasticities of all inputs are found to be positive and significant except for the farmyard manure. Water salinity has a considerable negative impact on date productivity. For the technical inefficiency model, none of the socioeconomic variables seem to matter.

Key Words: salinization, private and GIC systems, technical efficiency, Nefzaoua oases, date production, groundwater management

(ProQuest Information and Learning: ... denotes formula omitted.)

The Nefzaoua region is situated in the southwest of Tunisia under arid climatic conditions where the annual mean precipitation is 100 mm and the temperature exceeds 40 degrees Celsius (104 degrees Fahrenheit) in summer. It is an important source of date production in southern Tunisia, contributing up to 45 percent of total area under date production and more than 55 percent of total date production each year. The Nefzaoua Oases region is famous for the production of high-quality dates known as "Deglet Now." At the turn of the century, Tunisia was selling more than 20,000 metric tons on the world market, which accounted for more than half of Africa's total date exports or 10 percent of the total Tunisian agricultural export market value (Food and Agriculture Organization 2004). Date production in the Tunisia oases has increased significantly over the past three decades, due to expansion in the irrigated area as well as massive investments in irrigation development made by the government. Date production has increased from 58,800 tons in 1975-76 to 107,000 in 2001-02.

The source of irrigation in this entire region is the North-West Sahara Aquifer System (NWSAS). This system is one of the largest groundwater systems in the world. It consists of two main aquifers, the Terminal Complex (TC) and the underlying Intercalary Continental (IC), and covers in total an area of more than 10^sup 6^ km^sup 2^. It is shared as a resource by three countries: Algeria, Tunisia, and Libya. Both subterranean reservoirs were filled with fresh water during the wet quaternary period. The TC aquifer is lying under the entire Nefzaoua and formed by many sub-aquifers lying between 300-600 m in depth. It covers 350,000 km^sup 2^ of septentrional Sahara area. The important part is in Algeria. This aquifer has a different piezometric level depending on the thickness of the aquifer, which increases from the Djebel Tebaga to the southwest.

The IC aquifer is also formed by three subaquifers, lying between 1,000-2,200 m in depth. It covers 600,000 km^sup 2^ of septentrional Sahara area. The important part is in Tunisia. Its water has a temperature of +65°C (+1497deg;F). It is fed only from the extremities of the Saharan basin. Its formation seems to have happened in the quaternary precipitation periods. Isotopic dating shows ages between 28,000 and 42,000 years (Kassah 1996, Mamou and Kassah 2002).

The bulk of the water pumped from the system is utilized for the irrigation of approximately 14,000 km^sup 2^ of agricultural land. The present situation can be characterized as fossil groundwater mining, the total extraction being 80 mVs. While the stored amount of water would be able to sustain this extraction for another 10,000 years, the water comes at a price. …

Search by... Author
Show... All Results Primary Sources Peer-reviewed

Oops!

An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.