David M. Bell
3200 SW Jefferson Way
Contact David M. Bell
My current research focuses on understanding drivers of recent rapid changes in forest ecosystems by linking fine-scale demographic processes (growth, mortality, and recruitment) to coarse scale shifts in vegetation pattern. This work leverages both field and remotely sensed data to develop cross-scale linkages essential for robust geospatial predictions of forest change and vulnerability. Specifically, I am:
(1) Exploring the relationship between regional remotely sensed changes in forest ecosystems, spatio-temporal variation in climate, and stand- and tree-level forest inventory measurements to identify the forest and environmental characteristics associated with change and the contributions of tree mortality driven by drought, disease, and insect outbreaks.
(2) Quantifying uncertainties in vegetation mapping, such as the gradient nearest neighbor (GNN) imputation, to better understand the applicability and behavior of Landsat-based, multivariate vegetation mapping efforts across scales.
(3) Examining regional variation in forest and species productivity to identify the interacting effects of disturbance, climate, and forest structure of forest change throughout ecological succession.
My past work involved demographic and ecophysiological responses of individual trees to climate and competition in eastern US tree species, as well as the biogeography of tree mortality, recruitment, and occurrence in forests of the interior western US.
Why This Research is Important
Forest ecologists are increasingly tasked with predicting forest change and vulnerability in the face of climate change and disturbance. By linking fine-scale ecological processes to remotely sensed data, this research can provide insights into the interacting drivers of forest change and increasingly robust geospatial predictions. Such results are essential for planning and decision making efforts for an uncertain future.
- Duke University, Ph.D. Forest ecology 2011
- Northern Arizona University, M.S. Forestry 2005
- Colorado State University, B.S. Forestry 2002
- Postdoctoral Research Fellow, University of Wyoming
2011 - 2014
Featured Publications & Products
- Clark, James S.; Iverson, Louis; Woodall, Christopher W.; Allen, Craig D.; Bell, David M.; Bragg, Don C.; D'Amato, Anthony W.; Davis, Frank W.; Hersh, Michelle H.; Ibanez, Ines; Jackson, Stephen T.; Matthews, Stephen; Pederson, Neil; Peters, Matthew; Schwartz, Mark W.; Waring, Kristen M.; Zimmermann, Niklaus E. 2016. The impacts of increasing drought on forest dynamics, structure, and biodiversity in the United States.
- Bell, David M.; Bradford, John B.; Lauenroth, William K. 2015. Scale-dependence of desease impacts on quaking aspen (Populus tremuloides) mortality risk in the southwestern U.S..
- Bell, David M.; Gregory, Matthew J.; Ohmann, Janet L. 2015. Imputed forest structure uncertainty varies across elevational and longitudinal gradients in the western Cascade mountains, Oregon, USA.
- Bell, David M.; Ward, Eric J.; Oishi, A. Christopher; Oren, Ram; Flikkema, Paul G.; Clark, James S.; Whitehead, David. 2015. A state-space modeling approach to estimating canopy conductance and associated uncertainties from sap flux density data.
- Kennedy, Robert ; Ohmann, Janet ; Gregory, Matt ; Roberts, Heather ; Yang, Zhiqiang ; Bell, David ; Kane, Van ; Hughes, M Joseph; Cohen, Warren ; Powell, Scott ; Neeti, Neeti ; Larrue, Tara ; Hooper, Sam ; Kane, Jonathan ; Miller, David ; Perkins, James ; Braaten, Justin ; Seidl, Rupert . 2018. An empirical, integrated forest biomass monitoring system.
- Copenhaver-Parry, Paige E.; Bell, David M. 2018. Species interactions weakly modify climate-induced tree co-occurrence patterns.
- Bell, David M.; Cohen, Warren B.; Reilly, Matthew ; Yang, Zhiqiang . 2018. Visual interpretation and time series modeling of Landsat imagery highlight drought's role in forest canopy declines.
- Bell, David M.; Spies, Thomas A.; Pabst, Robert. 2017. Historical harvests reduce neighboring old-growth basal area across a forest landscape.
- Bradford, John B; Bell, David M. 2016. A window of opportunity for climate-change adaptation: easing tree mortality by reducing forest basal area.
- Bell, David M.; Gray, Andrew N. 2016. Assessing intra- and inter-regional climate effects on Douglas-fir biomass dynamics in Oregon and Washington, USA.
- Bell, David M.; Schlaepfer, Daniel R. 2016. On the dangers of model complexity without ecological justification in species distribution modeling.
- Bell, David M.; Clark, James S. 2016. Seed predation and climate impacts on reproductive variation in temperate forests of the southeastern USA.
- Gregory, Matthew J.; Yang, Zhiqiang; Bell, David M.; Cohen, Warren B.; Healey, Sean; Ohmann, Janet L.; Roberts, Heather M. 2015. Cloud-based computation for accelerating vegetation mapping and change detection at regional to national scales.
- Bell, David M.; Gray, Andrew N. 2015. Examining Pseudotsuga menziesii biomass change dynamics through succession using a regional forest inventory system.
- Bell, David M.; Gregory, Matthew J.; Roberts, Heather M.; Davis, Raymond J.; Ohmann, Janet L. 2015. How sampling and scale limit accuracy assessment of vegetation maps: A comment on Loehle et al. (2015).
- Moore, Lynn M.; Lauenroth, William K.; Bell, David M.; Schlaepfer, Daniel R. 2015. Soil Water and Temperature Explain Canopy Phenology and Onset of Spring in a Semiarid Steppe.
- Cohen, Warren B.; Yang, Zhiqiang; Bell, David M.; Stehman, Stephen V. 2015. US forests are showing increased rates of decline in response to a changing climate.
|How do old clearcuts affect old-growth?|
The edge influence of past clearcutting on the structure of neighboring uncut old-growth forests is widespread and persistent. These indirect an ...
|Wetter, warmer conditions will likely favor biomass accumulation in Douglas-fir|
Conversely, continued accumulation of forest biomass in drier regions may be more limited.