Continuous use, mostly by mono cultivation of cereal, of agricultural lands leads to soil degradation by tillage erosion, rain and wind - especially in the Mediterranean region - with consequences for the loss of organic matter, the destruction of the field and finally the gradual disappearance of topsoil. The creation of a permanent cover by implantation of a legume pioneer and rational exploitation of this system of crops allows the recovery of the biosphere and the return to productivity of the treated lands. An environmental management of degraded land under a rainfall less than 400 mm sets a positive development in these soils following a cultural practices described and implemented in Tunisia from 2003 to 2009 in the Goubellat region by AAG/SAG.
