Macrosystems as metacoupled human and natural systems

A early as 1942, ecosystems were depicted as multiple compartments coupled by directional fluxes of energy (Lindeman 1942). The concept of ecosystems as spatial entities with interrelated and interacting components has since been advanced as a result of work in several ecological subfields – notably landscape ecology in the 1980s (Urban et al. 1987) and more recently macrosystems biology (Heffernan et al. 2014). Macrosystems biology focuses on ecological processes occurring at scales ranging from regional to continental, and emphasizes teleconnections (ie phenomena that link geographically distant regions), macroscale feedbacks (ie amplified or diminished broad-scale feedbacks), and crossscale interactions (ie phenomena at one temporal or spatial scale influencing another) as fundamental characteristics (Heffernan et al. 2014). In addition, because of the ubiquitous influence of human activities, macrosystems are inherently interconnected, complex human–natural systems (Liu et al. 2015a). Human activities are influencing the spatiotemporal scales at which ecological processes operate (Rose et al. 2017). Spatially, human activities can induce processes to expand (eg larger dust storms due to reduced vegetation cover) or contract (eg anthropogenic channelization of rivers). From a temporal perspective, some processes accelerate (eg rates of sea-level rise) while others slow (eg persisting alterations in forest composition due to land-use change) (Rose et al. 2017). Such novel spatiotemporal combinations can result in new scaling rules for ecological processes, and can at times alter a system’s resilience by pushing it closer to a threshold beyond which the system can no longer retain its essential properties (ie a tipping point; Scheffer et al. 2001; Peters et al. 2004). Few studies have explicitly incorporated both local and distant interactions, feedbacks, and socioecological dynamics into macrosystems biology (as highlighted by Hefferman et al. 2014; Rose et al. 2017; but see Liu 2017). As a result, macrosystems research has tended to focus primarily on systems that are in close proximity or systems with exclusively long-distance teleconnections, such as those Macrosystems as metacoupled human and natural systems