Fig. 2. Human activities in most coastal zone systems lack functional feedback loops with the environment that they are impacting. This requires that either policy regulate these activities, or that the activities themselves become sustainably self-regulating, i.e., with regard to their impacts on natural and social subsystems of a coastal system. The black arrows designate the human activities that use the environmental system. The solid orange lines indicate the indirect feedback loops that policy might establish for the three categories of destabilizing human activities, and the orange dotted line is an additional potential direct feedback for Harvesting. The dark purple arrows indicate market influences on the human activities. The dark green arrows are the potential information feedback loop of the SAF.