1. Coupled Human and Natural Systems (CHANS)
Integrated systems in which humans and natural components interact.
Liu et al Sciecne
Diagram modified from

2. Examples of CHANS Social-Ecological Systems
Human-Environmental Systems
Society-Nature Systems
Population-Environment Systems
Ecological-Economic Systems
Social-Economic-Natural Complex Systems

3. Complexity of Coupled Human and Natural Systems Jianguo Liu, Thomas Dietz, Stephen Carpenter, Marina Alberti, Carl Folke, Emilio Moran, Alice Pell, Peter Deadman, Timothy Kratz, Jane Lubchenco, Elinor Ostrom, Zhiyun Ouyang, William Provencher, Charles Redman, Stephen Schneider, William Taylor
Reciprocal Effects
Feedback Loops
Nonlinearity
Thresholds
Surprises
Legacy Effects
Time Lags
Resilience
Heterogeneity
Liu et al 2007 Science

4. Example Questions to Address
How do different aspects of complexity vary and interact across space, over time, and at different organizational levels?
How do human decisions affect CHANS complexity?
How does CHANS complexity affect human decisions?

5. Status of CHANS Research
Interest in CHANS research is growing rapidly around the world.
Need more solid and comprehensive theoretical foundations
Go beyond traditional disciplinary theories
Need more powerful research tools
Agent-based models

6. Need and Opportunities for CHANS Research
Better understanding of global challenges
More informative for management, conservation, policy, and other arenas.
Funding agencies
The U.S. National Science Foundation (Dynamics of Coupled Natural and Human Systems Program)

7. International Network of Research on Coupled Human and Natural Systems (CHANS-Net.org) Sponsored by The National Science Foundation Coordinators Jianguo (Jack) Liu and Bill McConnell

8. Objectives of CHANS-Net
Promote communication and collaboration across the CHANS community.
Generate and disseminate comparative and synthesis scholarship on CHANS.
Expand and diversify the CHANS community.

9. CHANS Events at 2011 AAAS Friday, February 18
8: :30 am Convention Center, 140B
Mapping and Disentangling Human Decisions in Complex Human-Nature Systems
1:30 - 4:30 pm Convention Center, 140B
Telecoupling of Human and Natural Systems
Saturday, February 19
10: :30 am Convention Center, 146B
Resource use and Ecological Resilience in a Tropical Socio-Ecological system
1:00 - 5:00 pm Convention Center, Exhibit Hall D
Student Poster Competition
Sunday, February 20
The Challenge of Measuring Sustainability
General Poster Competition
1:30 - 4:30 pm Convention Center, 146B
Modeling Across Millennia: Interdisciplinary Paths to Ancient Socionatural Systems
Monday, February 21
9: :15 am Convention Center, 156
Social Networks and Sustainability