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The new forms of land development in the Algerian Sahara and the problem of the Acrididae Volume 13, issue 1, Mars 2002

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Author
Institut d'hydraulique et d'agronomie saharienne, Centre universitaire de Ouargla, BP 163, Ouargla 30000, Algérie.
  • Page(s) : 37-42
  • Published in: 2002

The new crop development system - cereal-growing under pivot irrigation - which public authorities are promoting in the Sahara is bringing about drastic changes not only with regard to the landscape itself but also in terms of techniques and ends. The irrigation of arid lands radically modifies living conditions as well as the vegetation. Oases are small closed ecological areas where living conditions are quite different from those which can be found in the surrounding desert. Crops themselves are the perfect nest for phytophagous migratory insects such as the Acrididae. Their very high breeding potential allows them to proliferate very rapidly, especially when they can enjoy adequate ecological conditions for multiplication, whether in a given spot or in different places where they can move and continue to develop. The presence of Locusta migratoria (Linné, 1758) all over the Sahara was not merely fortuitous, as it happens to be a favourable biotop for this locust. Simultaneously, the newly cultivated areas of the Adrar region in central Sahara have offered native individuals of Schistocerca gregaria (Forskål, 1775) favourable conditions for their development, multiplication and gregariousness at times when rainfall was very scarce all over the Sahara.