Since the early nineties in the last century, scholars are warning about the dramatic increase of the demographic and economic gradients from northern African to southern European countries and their consequences to the migration rates. Fifteen years after those predictions are becoming confirmed. Rather than looking at the whole intricacies of this migration process in the source and receptor countries, this contribution will focus on a particular issue: the environmental outcomes of the S-N flow of people and the inverse N-S flow of capital as remittances. To this purpose a micro-approach will be adopted by considering the situation in a set of oasis in Morocco and Tunisia, and in the coastal intensive agriculture of Spain.

A conceptual background will be adopted, in which desertification is thought as a break of sustainability in the human-renewable resources system, due to disturbances that were not incorporated in its previous history. Such disturbances may be climatic, demographic, economical, technological, institutional, etc. Their common effect is that produce an uncontrolled over-exploitation of the resources.

There is not general evidence that emigration is triggered by desertification. In Morocco, the traditional sources of migration are related to lack of life horizons for an increasing population in closed environments with limited resources rather tat to the loss of resources by desertification.

The inverse flow of people and remittances in coupled migratory systems may have similar effects at the source and receptor areas, in the sense of increasing desertification risk.
Immigration in recently developed agricultural areas that have not yet build up their own internal cooperative systems to keep sustainability, may impair or delay this process by lowering labour costs, the main component of fixed costs per unit area.