Christian is Professor of Archaeology, Dept of Historical Studies, University of Gothenburg. His main research specialization is the prehistory of the Lowland Maya of Mexico, Guatemala, and Belize. He also studies the prehistory of the Central Andes (Bolivia) and the Amazon (Brazil). He is interested in issues of long-term sustainability and resilience and apply a historical ecological lens to study urbanism, farming systems, water management, and socio-political organization, with a particular focus on urban farming.