Settled agriculture is restricted to the strip of land along the Senegal River and to oases in the north; only 0.2% of Mauritania's total land area is classified as arable. In general, landholdings are small. Overall agricultural development has been hampered not only by unfavorable physical conditions but also by a complicated land-tenure system (modified in 1984) that traditionally rested on slavery, inadequate transportation, and the low priority placed on agriculture by most government developmental plans. The country's traditional dependence on food imports has been heightened by drought. Agriculture's share of GDP has been steadily falling; in 2001 it stood at 21%, down from 29% in 1987.
Millet and sorghum production reached 10,000 and 75,000 tons, respectively, in 1999. Other crop production in 1999 included paddy rice, 102,000 tons; and corn, 8,000 tons. Date production was 22,000 tons in 1999.
The Mauritanian government is encouraging agricultural development of the Senegal River valley. The OMVS began in 1981 to build a dam at Manantali, in Mali, for purposes of river transport, irrigation, and hydroelectric power. In conjunction with this OMVS project, Mauritania initiated an irrigation and development scheme in 1975 for the Gorgol River valley, involving construction of a dam; the scheme would increase arable land by over 3,600 ha (9,000 acres). This project was to be followed by other dams that together would add 30,000 ha (74,100 acres) for food production. Another OMVS project, begun in 1981, was designed to block salt water from entering the fertile Senegal River delta. From 1989 to 1991, a series of measures aimed at stimulation and rationalization of agricultural production were initiated, including producer price increases, marketing and distribution liberalization, and streamlining of government-owned agricultural organizations.