Common core themes in geomorphic, ecological, and social systems.

Core themes of geomorphology include: open systems and connectivity; feedbacks and complexity; spatial differentiation of dominant physical processes within a landscape; and legacy effects of historical human use of resources. Core themes of ecology include: open systems and connectivity; hierarchical, heterogeneous, dynamic, and context-dependent characteristics of ecological patterns and processes; nonlinearity, thresholds, hysteresis, and resilience within ecosystems; and human effects. Core themes of environmental governance include: architecture of institutions and decision-making; agency, or ability of actors to prescribe behavior of people in relation to the environment; adaptiveness of social groups to environmental change; accountability and legitimacy of systems of governance; allocation of and access to resources; and thresholds and feedback loops within environmental policy. Core themes common to these disciplines include connectivity, feedbacks, tipping points or thresholds, and resiliency. Emphasizing these points of disciplinary overlap can facilitate interdisciplinary understanding of complex systems, as well as more effective management of landscapes and ecosystems by highlighting drivers of change within systems. We use a previously published conceptual framework to examine how these core themes can be integrated into interdisciplinary research for human-landscape systems via the example of a river.