Thomas Doyle, Ph.D.



Ph.D., Systems Ecology, University of Tennessee, 1983

M.S., Systems Ecology, University of Tennessee, 1980

B.S., Biology, Northeast Louisiana University, 1976


Thomas Doyle's research focuses on developing integrated simulation models of plant growth and succession at the leaf, tree, stand and landscape levels. His models have predicted effects of natural and anthropogenic disturbance on the structure and function of coastal and floodplain forests. He applies dendroecological techniques of tree-ring analysis for climate reconstruction, disturbance interventions of floods and hurricanes, and forest model validation. Current ecosystem model applications include projected impacts of global climate change, sea-level rise, elevated carbon dioxide, and hurricane impact along with resource management issues of wetland restoration, fire, wastewater pollution, and landscape fragmentation.

Ecosystem analysis and modeling with a special emphasis on tree-ring applications, forest succession, and landscape simulation models, role of natural and anthropogenic disturbance and climate change on forest structure and diversity of coastal ecosystems of the southeastern United States and Caribbean regions.  


Doyle's research spans several decades of developing spatial simulation models for temperate and tropical ecosystems from mangroves, tidal freshwater forested wetlands and marshes to floodplain swamp forests, pine flatwoods, and montane eastern deciduous and tropical rain forests. His field and modeling research takes an integrated hierarchical approach to understanding physiological processes at the leaf layer and plant level, to competition and spatial relations of tree canopy and species dynamics at the stand and forest level, and landscape scale exchange of physical forcings of climate, flooding, fire, storms, and management of riverine and coastal systems. His dendrochronology research has shown that hurricane wind and surge evidence is imprinted in the growth record of surviving trees in coastal counties and that tree-ring chronologies from coastal locations are problematic for climate reconstruction for confounding storm influences.  His tree-ring collections in riverine floodplains shows that streamflow records are valuable climate proxies for rainfall distribution annually and seasonally, and that different tree species respond to temperature and precipitation to different degrees such that multi-species approach is more comprehensive for climate reconstruction than single species models.  His hurricane research and models are based on dozens of post-storm assessments in mangrove and tidal freshwater forests across the southeastern U.S., Caribbean, and Central America.  These investigations and tools have shown that hurricane intensity and frequency are important determinants of ecosystem type and structure based on measured species sensitivity to windthrow and surge impact.  Long-term permanent plot studies have proved invaluable to capture the effect of storm surge suppression and saturation from direct and indirect, tropical and extra-tropical storm events on species distribution and forest succession. The ubiquitous presence of forest degradation and dieback at the ecotonal interface of marsh and tidal forest has been shown to result from an important interaction of supra-storm tides and coincidental drought to raise soil salinities, acutely and incrementally, in near coastal settings long before chronic sea level and normal tides dictate habitat succession. Doyle has developed a number and variety of sea-level rise models by function and primary ecosystem demonstrating hindcast and forecast applications for predicting coastal forest retreat and marsh migration at park, county, and ocean basin scales.  These tools have also been used to evaluate the vulnerability of coastal marshes where expansion of mangrove into temperate clines from warming climate, sea-level rise, and hurricanes can inform management, restoration, and adaptation strategies in the Gulf coast and delta’s worldwide.


Doyle worked in the Global Carbon Cycling and Biomass for Energy programs of the Department of Energy at Oak Ridge National Laboratory, Tennessee, before joining the U.S. Geological Survey, National Wetlands Research Center, Lafayette, Louisiana in 1989.