The results of the environmental project, based on geomorphological, sedimentological, and micromorphological analyses, radiocarbon determinations and pollen studies suggest that the period of higher water accessibility in the region persisted throughout the entire Bronze Age (c. 3000-1200 BC), the period which saw the greatest flourishing of the city and surrounding region. From the Iron Age onwards (c. 1200-600 BC), however, the available evidence indicates a reduced water supply. The progressive drop recorded in the level of the lakes and in the rivers’ flow and the gradual transformation of the former into swamps might have been one of the factors (the others being political and socio-economic), which brought about the abandonment of Mishrifeh at the end of the Iron Age.In order to understand the effects of the ancient town expansion on the pre-existing landscape, an intensive coring programme was carried out inside Mishrifeh’s urban perimeter and in the ditches outside its northern and western ramparts.
The occurrence of lake deposits at the base of the fill of the northern and western ditches indicates that a permanent water body which was fed by the river network and a system of karst springs, rising from the limestone bedrock, existed immediately to the south, west and north of the city.
At the beginning of the Middle Bronze Age (c. 2000-1600 BC), the city’s defences were built. Their construction required a large quantity of earth and stone, obtained from the local bedrock. The western and the northern ramparts were built inside the area occupied by the lake and as a consequence the cores of these are partly composed of lacustrine peat deposits.
The lake was divided by the ramparts into two parts: a smaller portion was trapped inside the perimeter of the town and continued to be fed by a karst spring located at the northern foot of the acropolis. The largest part of the lake, however, constituted a sort of reservoir upstream of the city, which was dammed by the southern and western ramparts and their northwestern corner.
Both lakes were probably used as fresh water reservoirs for the inhabitants of the city and their animals and for irrigating fields and orchards in the city itself and in the surrounding countryside.The existence of a lake fed by a network of karst springs appears to have been strategic for the location of Bronze Age Qatna. The pollen content of lake sediments indicates a major change in the vegetation of the region during the Middle Bronze Age. This modification of the natural environment was probably related to the impact of human productive activities on the vegetation. This is evidenced by the dramatic deterioration which occurred in this period of the local open woodland, characterised by scattered juniper and oaks, and the presence in the pollen diagram of several pollen types related to intensive land management (e.g. cereals, nettle etc.). The palynological evidence therefore suggests the systematic deforestation of the territory around Qatna, probably connected to the need to devote all cultivable land to intensive agriculture in order to support the massive urbanization of the site which occurred during the early second millennium BC.