Conclusions

Whatever the circumstances attending the decline of the ancient civilizations of the desert, the basic principles of their pioneering methods of land and water husbandry may well be relevant today. In many of the desert fringelands around the world, where more people than ever are now struggling with the age-old problems of aridity, the old principles can be adapted and applied to great benefit. Much can be done to improve water harvesting and storage by means of modern technology. Power-driven earth-shaping machinery can be used to build parallel dykes across the slope, and to direct and spread overland flow. Moreover, stable chemical agents can be used to seal, waterproof, and stabilize run-off-yielding surfaces, as well as water reservoirs. Provision can be made for the eventuality of drought by storage of water and grain, by conservation and judicious tapping of underground water resources (aquifers) for supplementary irrigation, and by keeping range-land reserves.

We end with a word of caution. Modern means should be employed with great care, so that the localized utilization of land and water resources in restricted areas for the benefit of humans will not endanger the larger desert environment with its inherently fragile ecology and diverse biota. Humanity and nature can and must coexist, in the desert as elsewhere.