Dégradation de la qualité des sols sous serres en zone saharienne. Cas de la région de Biskra (sud est-Algérie).

Abstract

In the region of Biskra, one saw to be born in about ten years an important basin of production of which one says that he/it is the first in Algeria for the cultures under abris; avec more of more than 1400ha.Long-term, one attends the deterioration of the quality of the agricultural production and a deterioration of soils under the effect of the saltiness. In this context, our work is about the saltiness of soils under greenhouse tothe level of the experimental station of the Technical institute of the Development of the agronomy Of the Sahara (I.T.D.A.S) of Ain Benoui to 10km Southbound west of Algiers is of Biskra and 600 km to the South. To the term of this work, we could put in evidence some milked of evolution of the saltiness of soils submitted to the irrigation (under greenhouse) in relation to those of the witnesses (non cultivated). One selected two cultivated greenhouses and irrigated by the system drips to drop, one of them is situated meadows of the drain and the other moved away of this last with a witness (soil non worked). He/it comes out again that the water of irrigation is salted excessively and that soils are generally salted to greatly salty Between the withdrawal of soil of March and the one of September 2003, we noticed an increase of the saltiness in the greenhouses as well as in the witness under the effect of the strong evaporation in summer and of gone it back up capillary of the tablecloth. On the other hand,one noticed that the greenhouse situated far from the drain underwent an accumulation of salts in the root zone as well as in the witness in spite of the presence of a drainage network situated to some meters. However, the greenhouse situated all around immediate of the drainage channel recorded a washing accentuated of salts in this zone. It lets think that this kind of earths sandblasting machines irrigated with a loadedwater can behave in an exemplary manner if they are drained well. That is to say with a network of drainage very brought closer of the greenhouses.