Human ecosystems are real-life systems characterized by very strong and longterm interactions between human communities and their environment; as such they constitute an expansion of the ecological concept of ecosystem. According to Stepp and colleagues (2003), human ecosystems not only process matter and energy flows, but - and more specifically - information flows as well. Therefore, they display very specific characteristics due to our ability to communicate and learn from others, creating the conditions for co-evolutionary processes in which chance lends a hand to necessity. Bradbury (2006) argues that, until recently, human beings had been able to adapt to changes and to cope with co-evolution through rather simple heuristics. But human activities have gradually strengthened the links globally between loosely connected environments and societies. More information, more interactions and shorter communication paths tend to create intractable dependencies between events and to generate deeper uncertainties overall