Comparative Stability and Resiliency of Ecosystems: Five Centuries of Human Interactions with the Environment on the Eastern Shore of Virginia

Coupled natural-human ecosystems now tessellate the terrestrial surface of the Earth. There is little land that is not to some degree a consequence of its human inhabitants. Given the capacity of modern societies to alter both the atmosphere and ocean, even remote and unpopulated landscapes are to some degree altered by human activity. But does this human activity affect the stability of the natural-human system? What is the natural-human systems resistance to change? What is its resilience (the likelihood of returning to its original state after being disturbed)?

While people often assume that the answer to these questions must be in the affirmative, this project will assess the question quantitatively and qualitatively through advanced socio-environmental systems analysis. This proposal will characterize, quantify, and model the spectrum of coupled natural-human dynamics on the Eastern Shore of Virginia over the past 500 years as, first, Native Americans and, later, European and African colonists and their descendents interacted with their environment.

This interdisciplinary study is designed to improve understanding of the complex dynamics of a tightly coupled natural-human system in a single locale, but at varying spatial and temporal scales and under differing social and environmental pressures. These efforts will culminate in the development of integrated human-ecosystem models, which will be parameterized, calibrated, and validated by historical, archaeological, ecological, and geochemical data to simulate natural-human systems during specific historical periods that represent changes in human demographic patterns, land-use practices, and technological capabilities: Protohistoric (1550-1610); Colonial (1650-1700); Late Plantation (1800-1850); Commercial/Industrial (1850-1950); and Modern/Conservation (1950-present).

Three working hypotheses will be investigated to understand and compare a range of landscape- and seascape-scale ecosystems in terms of their dynamic responses: (1) Systems with more technological societies are better able to resist change from environmental perturbation. (2) Systems with more technological societies are more resilient to environmental perturbation. (3) Technological societies are themselves the critical environmental perturbation that drives the future status of the system. Principal component analysis and other quantitative procedures will be employed to assess system stability, resiliency, and resistance to change during and between these time periods and to identify those system components within time periods that are most critical to resistance, resilience, and stability.

Anticipated intellectual contributions of this project include identifying constraints imposed by nature on humans in order to explain the range of adaptive poses assumed by human societies, assessing the response of the greater natural-human system to the activities of human societies over a broad range of time periods and through examination of distinctive demographic, land use, and technological regimes within the same locale.

Anticipated broader impacts of this project include increase knowledge about natural-human dynamics on the Eastern Shore of Virginia, in particular, and countless other inhabited land-water interfaces throughout the world in general. The project will identify variables critical to system resistance, resilience, and stability, thereby informing policymaking in the Chesapeake Bay watershed and similar locales throughout the world. The project also will provide education and training opportunities for K-12 students, undergraduate and graduate students, and the general public. This project is supported by an award resulting from the FY 2003 special competition in Biocomplexity in the Environment focusing on the Dynamics of Coupled Natural and Human Systems.