| Abstract: | Comparison between desert soils which have no history of cultivation with those which have been farmed near oases or by the use of some sort of irrigation shows that farming practices have left a permanent record in the soil profile. The salt content of the soil bears a direct relationship to the age of cultivation, the highest values being found in soils which carried Chalcolithic farming as far back as the 3rd millennium BC. Increased humus content and evidence of biological activity are also found in old cultivated soils, as well as inclusions such as clay brick fragments, pottery and charcoal. |
