Shifting the Sands – Early Islamic Modification of the Caesarea Sandy Lowlands into Plot-and-Berm Water-Harvesting Agroecosystem

During the Early Islamic period, several emerging agricultural innovations enabled the cultivation of summer crops in unproductive Mediterranean lands. This necessitated the development of water harvesting methods. This study delves into the creation of the Plot-and-Berm (P&B) agroecosystem along the sandy coast of Caesarea, Israel. From the early tenth century to the mid-twelfth century, coeval to the later part of the Early Islamic period and the beginning of the Crusader period, a 1.5 km2 P&B agroecosystem was constructed and maintained. Remarkably, this system still dominates the landscape. The agroecosystem’s expansion was controlled by regional hydrological, geological, and climatic factors. Anthropogenic sedimentary units include the anthrosol found within the plots and anthrosediment within the berms with densely added refuse. Sedimentological and mineralogical analysis of the anthrosol and anthrosediment unveils the additives of calcitic fine-grains, likely originating from nearby kilns. The arrangement of these fine grains amidst quartz particles fills pore spaces, reducing the hydraulic conductivity of the natural sand. Similar to other sandy agricultural systems, morphological and sedimentological adaptations were employed to sustain a pattern of annual crop yields, by capturing rainfall water for crop cultivation during the rainy season, while high groundwater levels facilitated summer cultivation.