(Above) Diagram of the syndromes concept.

Researchers have increasingly focused on the interactions and connections between ecosystems and humans. Through the greater use of resources, increases in pollution, and changes in land use, humans have changed the ecosystems around them. Human activities such as urbanization and intensification of agriculture lead to an increase in road and housing density, oil and gas usage, and necessary infrastructure such as utility transmission corridors. While it is clear that such shifts in land and resource use impact our environment, current research shows that linking the changing population to specific ecosystem change is not simple (Meyer 1996; Harte 2007). Measuring these impacts in protected areas provides an additional layer of complexity, as the source of the ecosystem stress is often found off-site. Although those who manage protected areas, such as the National Park Service (NPS), understand there is a link between encroaching human populations and a change in ecosystem health of the protected area, untangling specific causes of change has proven difficult. With this in mind we aimed to develop a conceptual framework for using available social, economic, and environmental indicators to give land managers new tools for understanding the potential ecological ramifications (effects) to park resources of adjacent socioeconomic stressors (causes). What emerged from this process was the “syndromes” approach. This is a new method for categorizing impacts to park ecosystems that moves away from trying to find one-to-one relationships between socioeconomic factors and ecosystem changes in protected areas. Establishing such relationships is extremely difficult and we therefore suggest this holistic approach to gaining insight into how socioeconomic factors effect park ecosystem changes. When one or more syndromes are found to be influencing a protected area, the protected area would benefit by monitoring the factors involved, such as encroaching development, mining, ranching, and public use.