s:615:"TY General LB CIFORHQ 7406 CY International Union of Forest Research Organizations (IUFRO) AB In this chapter, we review current scientific understanding and hypotheses at seven system delineations that build up from the level of a ‘tree’ interacting with water, to that of a social-ecological system at the scale of landscapes. A system delineation separates internal entities that interact dynamically from external entities that may have a one-way influence but are not significantly influenced by feedback from within the system boundaries. Each system level has its characteristic outcomes or results. ";