Coupled Human And Natural Systems Framework (CHANS Framework)
Human-nature systems used to be studied largely either in separation or with unidirectional connections: when human systems were studied, they were considered to be constrained by, or with input from/output to, natural systemsí¬put another way, natural systems were only considered as context or background. On the other hand, human systems were often viewed as exogenous influences when studying natural systems. This disciplinary chasm, in parallel with unidirectional connections between natural and human systems, has been shown unable to explain many complexity features (e.g., feedback, nonlinearity and thresholds, heterogeneity, time lags) in human-nature systems.
The coupled human and natural systems (CHANS) are integrated systems in which people interact with natural components. The CHANS concept has evolved in parallel with many closely related concepts, including coupled natural and human (CNH) systems, human-environment systems (Turner et al. 2003), social-ecological systems (SES; Ostrom 2007), and social-environmental systems (Eakin and Luers 2006). The CHANS framework addresses complex interactions and feedback between human and natural systems, which necessitates inclusion of biophysical/ecological variables and human variables, participation of biophysical/ecological and social scientists, use of tools and techniques from multiple biophysical and social sciences, etc.
An, L., A. Zvoleff, J. Liu, and W. Axinn (2014). Agent based modeling in coupled human and natural systems (CHANS): Lessons from a comparative analysis. Annals of Association of American Geographers 104(4):723-745.
An, L. 2012. Modeling human decisions in coupled human and natural systems: review of agent-based models. Ecological Modelling 229(24): 25-36.
Liu J, T. Dietz, S.R. Carpenter, M. Alberti, C. Folke, E. Moran, A.N. Pell, P. Deadman, T. Kratz, J. Lubchenco, E. Ostrom, Z. Ouyang, W. Provencher, C.L. Redman, S.H. Schneider, and W.W. Taylor (2007). Complexity of coupled human and natural systems. Science: 317:1513-16.
Liu, J., T. Dietz, S.R. Carpenter, C. Folke, M. Alberti, C.L. Redman, S.H. Schneider, E. Ostrom, A.N. Pell, J. Lubchenco, W.W. Taylor, Z. Ouyang, P. Deadman, T. Kratz, and W. Provencher (2007). Coupled human and natural systems. AMBIO: A Journal of the Human Environment 36(8):639-649