Top-down and bottom-up water management: A diachronic model of changing water management strategies at Angkor, Cambodia

International audience; The Greater Angkor region, in northwestern Cambodia, was home to several successive capitals of the Khmer Empire (9th to 15th centuries CE). During this time, the Khmer developed an extensive agricultural and water management system characterized by top-down state-sponsored hydraulic infrastructure. Archaeological evidence now shows that the well-documented state temples and water management features formed the core of an extended settlement complex consisting of many thousands of ponds, habitation mounds, and community temples. These community temples are difficult to date, and so far, the lack of chronological resolution in surface archaeological data has been the most significant challenge to understanding the trajectory of Angkor's growth and decline. In this paper, we combine heterogeneous archaeological datasets and create diachronic models of the landscape as it was developed for agricultural production. We trace the foundation of new temple communities as they emerge on the landscape in relation to the construction of extensive state-sponsored hydraulic infrastructure. Together, these two forms of water management transformed over 1000 km 2 of the Greater Angkor Region into an elaborate engineered landscape. Our results indicate that, over time, autonomous temple communities are replaced by large, state-sponsored agricultural units in an attempt by the state to centralize production.