Adaptive Systems Management in Acid Deposition Stressed Northern Forest Ecosystems
Tammy Coe and Jon Erickson, The Rubenstein School of Environment and Natural Resources, The
University of Vermont, Burlington, Vermont, 05405, USA
Acid deposition poses a serious risk to forests in the northeastern United States. Research has
shown that additions of acidic sulfur and nitrogen compounds leach calcium from soils and foliage, an
integral input to a plant’s stress response system. This calcium depletion has been linked to increased
susceptibility to normal environmental stressors such as low winter temperatures, drought, insects and
pathogens in several tree species. Trees are generally resilient to such stress, able to make physiological
adjustments without significant changes in ecosystem function. However, acid deposition effects on forests
may reveal a unique threat to resilience by reducing the system’s ability to withstand change, potentially
resulting in a catastrophic shift to an alternative state. From a policy perspective, although the U.S. Clean
Air Act has successfully reduced emissions of acidic compounds from industrial sources, geographicspecific reductions are necessary to mitigate decades of acidic inputs and protect the resiliency of forest
ecosystems. To take into account the potentially cumulative effects of suppressed stress response systems,
policy goals should be reoriented toward resiliency and vulnerability of systems rather than on traditional
marginal damage assessments. Toward this end, this presentation will outline a modeling framework to
evaluate the effects of acid deposition on forest resilience in the northeastern U.S. based on various
emissions and policy scenarios.
Tammy Coe
The Rubenstein School of Environment and Natural Resources
The University of Vermont
Aiken Center
Burlington VT 05477
802.656.3269
802.656.8656 (fax)
Tammy.Coe@uvm.edu
Possible Topic Sessions:
Transboundary resource management
***Resilience
Ecosystem health and environmental indicators