The future of human-landscape interactions: drawing on the past, anticipating the future.

Without question, humanity is at a crossroad amidst rapid environmental changes. Some of these changes are natural, such as climate variability, but human-induced alterations on Earth have accelerated in recent decades, reaching a scale and intensity like never before. Virtually no place on Earth remains untouched by human activity. With a growing human population expected to exceed 10 billion people in coming decades (United Nations 2010), human interactions with Earth will likely continue to accelerate. A formal proposal to name a new timeframe within the Geological Time Scale, the ‘‘Anthropocene’’ (Crutzen and Stoermer 2000), is in development for consideration by the International Commission on Stratigraphy (Zalasiewicz et al. 2011). This proposed geologic timeframe recognizes the undeniable role of human activity in affecting Earth’s functioning, and is now widely debated among academic scientists, practitioners, and the public alike (e.g., Balter 2013). In light of increasing recognition of human interactions with Earth, this special feature explores new scientific questions and frameworks for tackling research frontiers for understanding human–landscape systems. These questions and frameworks derive from multidisciplinary perspectives, developing from discussions among 50 physical, social, and biological scientists gathered in a 3-day workshop sponsored by the U.S. National Science Foundation (NSF), held at the University of Oregon, USA (Chin et al. 2010). The workshop responded to a need to catalyze new research paradigms about the future of Earth’s surface in light of increasing human interactions. Outlined in recent reports to NSF’s Geosciences Directorate (NSF 2009; NRC 2010), these paradigms require development of new theories and predictive capacity for integrated human–landscape systems. In particular, the report by the U.S. National Research Council, Landscapes on the Edge: New Horizons for Research on Earth’s Surface (NRC 2010) identified a Grand Challenge in: ‘‘How will Earth’s surface evolve in the ‘‘Anthropocene’’? In highlighting the need to account explicitly for human–process interactions in understanding the change on Earth’s surface, the report recommended creation of new collaborations across the geosciences, biological sciences, social sciences and engineering, in addition to development of new conceptual frameworks and methods. Team-based interdisciplinary studies of Earth’s surface processes were also a primary recommendation in NRC’s 2011 report, New Research Opportunities in the Earth Sciences, specifying development of models of the active role of humans in landscape change. The papers in this feature contribute to a view of human–landscape systems in which advances in a range of disciplinary sciences feed into an integrated core (Fig. 1; Harden et al. 2014, this issue). These disciplines span the social, biological, and geological sciences and include anthropology, archeology, atmospheric science, ecology, economics, geography, geomorphology, political science, and sociology. Harden et al. provide an overview of the science of human–landscape systems as explored in the 2010 Oregon workshop. Key questions are identified within contributing disciplines, leading to a discussion of A. Chin (&) University of Colorado Denver, Denver, CO, USA e-mail: anne.chin@ucdenver.edu