Character and Evolution of Sunken Groundwater-Harvesting Agroecosystems in Aeolian Sand since Early Islamic Times, between Iran and Iberia

By reviewing traditional, sunken, groundwater-harvesting agroecosystems (SGHAS) in coastal and inland aeolian sand situated in Iran, Egypt, Gaza Strip, Algeria and Iberia, coupled with image interpretation and geospatial analysis, we study the innovation and function of recently excavated Early Islamic (EI; tenth-twelfth century), Plot-and-Berm agroecosystems along the southeastern Mediterranean coast of Israel. The SGHAS and EI agroecosystems, usually affiliated with nearby towns, possess an aeolian sand substrate enrichened with urban refuse and/or organic material. The long-term investment in SGHAS attained profitable water security in the form of temporally continuous, shallow groundwater, replenished by rainfall. The crops in SGHASs include a wide range of vegetables, watermelons, dates and grapes, implying that the EI crops were partly or fully different. The spotty, historic appearance of SGHAS since the fifteenth–sixteenth centuries temporally lags after the abandonment of the EI agroecosystems, does not support spatial and temporal connectivity of sand agriculture knowledge, but probably exemplifies the appearance of site-specific ingenuities derived from growing agro-technological knowledge, crop variety and needs for food security. This study demonstrates the importance of traditional analogues for interpreting research gaps of archaeological, agricultural landscapes and provides insight for establishing traditionally-based, sustainable agriculture in sand.