Multiple Stressors in Coastal Systems

Among the most important challenges facing conservation biology today is the problem of predicting, understanding, and reducing effects of multiple stressors. Most, if not all, marine systems are exposed to multiple consequences of human activities. Areas near centers of dense population and commerce are often overfished, exposed to repeated introductions of invasive exotics, and serve as the receiving waters for both nutrients and contaminants. More remote areas can be influenced by larger scale stressors such as global climate change, ozone depletion, and overfishing of oceanic species, as well as by long-distance consequences of smaller scale perturbations.

In spite of the inherent difficulties, it is important for successful natural resource management and conservation that managers, researchers, and policy makers consider the myriad of stressors to which natural systems are exposed. Multiple stressor interactions not only alter the magnitude of stressor effects, but also alter the patterns of variability and predictability on which management strategies often rely. Studies that focus too narrowly on a single stressor can miss the simultaneous influence of other stressors, thus compromising the utility of results. Similarly, policies that focus on single stressors can also be less successful or cost-effective than actions that take a more holistic approach.

Directly addressing the complexity of multiple human influences on natural systems, along with the complexity of the systems themselves, will provide the greatest chance for successful conservation and management efforts.

We are currently collaborating with the SERC Nutrient and Ecological Modeling Labs, as well as colleagues at Cadmus, University of Maryland , and University of Virginia to understand how the Patuxent River and similar coastal systems are influenced by management decisions and other human activities.