Database: Agriculture
The Umayyad and Abbasid periods corresponded with important advances in agriculture across the caliphal territories. They were facilitated by the size of the empire and a taxation system which favored irrigated lands. Even though this period has sometimes been called an agricultural "revolution", it mostly took the form of an expansion, intensification and spread of existing techniques.
Pre-existing infrastructures such as Roman or Persian aqueducts, canals and reservoirs were expanded and brought to previously arid lands. The use of agricultural devices such as watermills, animal- powered water lifts (saqiya) and water screws, known across the Mediterranean but sparsely used until then, became widespread. Crops common in the Eastern parts of the empire, such as sugar cane or bananas, were adapted to new environments from Egypt to Iberia and North Africa. The results were higher yields, larger cities... and plenty of citrus fruits!
These developments went together with a consolidation of land ownership into the hands of the elite. Large-scale irrigation works were lucrative but costly and could only be paid for by already wealthy landowners. The Abbasid period is therefore characterized by the expansion of huge estates to the detriment of smaller farmers, leading to widespread discontent.