In Tunisia, only 30% of mobilized water resources have salinity less than 2.34 dS/m. The objective of this work was to determine the best irrigation scheduling way when saline and desalinated waters are used. Different irrigation doses of freshwater and saline water are used: T80-20, T50-50 and T1d-1d. 80, 20 and 50 correspond to the percentages of irrigation water supplied in a day. For 1d-1d, this corresponds to irrigation one day with saline water and then the next day with desalinated water. Their effect on crops growth and on soil salinity was measured for three different saline waters (1.56, 4.68 and 7.81 dS/m). For irrigation with water salinity of 1.56 dS/m, the treatments T50-50 gives the better yield. For the 4.68 and 7.81 dS/m, a reduction in height was observed for all treatments. Also, for soil salinity at the end of the lettuce crop cycle, T50-50 is the best treatment that has given the best results at all levels.
In arid countries like Tunisia, the need to find new sources of water for irrigation has become imminent. Desalination of seawater can be an alternative to irrigation. In this article, we take a look at the leading food companies specializing in desalination for irrigation around the world and the prospects for the solar energy desalination potential for irrigation in Tunisia. We have noticed that several companies invest money to desalinate water for agricultural purposes. However, the cost of a cubic meter of water sometimes remains high to go forward in this new technology.
