- Ph.D., Forest Biometrics, University of British Columbia, 2004
My research covers a broad range of topics, including mixed effects models in forestry and natural resources, design and analysis of experimental data, quantifying size and structure distributional differences in natural systems, and quantifying model uncertainty. My research aims to promote better conservation and management of natural resources by developing a better understanding of the dynamics of natural systems. My research is in three main areas: 1) advancing models of carbon fluxes derived from eddy covariance (EC) studies, 2) developing models characterizing the population dynamics of Bertholletia excelsa (Brazil nut); and 3) enhancing models of urban forest structure and growth, and their responses to exotic invasive woody species.
Models of Brazil nut. The Brazil nut is an economically important non-timber forest species that is collected exclusively in old-growth mixed-species forests largely by rural forest dwelling peoples in Brazil, Bolivia, and Peru. The management of these species and others in the Amazon basin is paramount in sustaining rural peoples and reducing rural poverty in the region. Data on this species present challenges, as they tend to be collected on multiple scales. Moreover, matching phenological cycles and external climate data is difficult, as the Brazil nut fruiting cycle takes 15 months to complete. To reduce the complexity of data, I use time series methods to identify cycles and cross-correlations, and mixed modeling techniques to ensure that temporal and spatial correlation structures are specifically accounted for using both small-and large-scale models of correlation. Models of small-scale correlation can be useful in quantifying inter- versus intra-genotypic competition, whereas models of large-scale correlation may help quantify environmental variability, such as the effect of soil type on competitive interactions among trees. Together with my colleagues, I have developed models of growth, production, and regeneration for this species that are a key part of its management, supporting human well-being in the region.
Urban and community forests. I have been active in developing models to describe urban forest structure and function throughout the southeast US and Puerto Rico. These models are essential to quantify the important ecosystem services provided by community trees, such as pollution removal and C sequestration. Urban landscapes are also key ecosystems, in that most alien invasive woody species originate there. However, we know very little about the factors influencing their distribution in urban ecostems, and what variables affect the spread of these species into adjacent peri-urban areas. Through a grant from the USDA, I am investigating the distribution of alien invasive woody plant species within two tropical metropolitan areas: San Juan, Puerto Rico and Miami, Florida. We have found that the distribution of invasive woody species is greatly affected by socio-economic and biophysical variables, and human population demographics. Moreover, the landuse history of these two areas has lead to two distinct invasion patterns. This research has added new information about the primary mechanisms by which invasive species spread.
Models of CO2 fluxes. Data from EC studies are generally processed at a half-hourly time intervals, along with environmental and micrometeorological variables. EC towers are often set up to measure changes in fluxes associated with environmental conditions such as changes in fire regime or climate change. However, few studies have statistically tested the drivers of carbon flux in a rigorous sense. Because of complex and long-ranging autocorrelative structures in the data, most researchers summarize data (e.g., monthly) to meet assumptions of independence necessary for analysis. However, non-normality in these distributions may bias summarized data. Instead, my research promotes time series methods to identify the drivers of CO2 fluxes. Incorporating these methods into flux research will aid in better quantification of sequestration/ emission of greenhouses gases between terrestrial biomes and the atmosphere.
(* indicates graduate students under my supervision)
Whelan, A., G. Starr, C.L. Staudhammer, H. Loescher, and R. Mitchell. Effects of drought and prescribed fire on energy exchange in longleaf pine ecosystems. Accepted to Ecosphere.
*Malone, S.L., Keough, C., Staudhammer, C.L., Ryan, M.G., Parton, W.J., and Starr, G. Ecosystem persistence in the face of climate change: A case study from the freshwater marshes of the Florida Everglades. Ecosphere 6(4): Article 57.
Staudhammer, C.L., F.J. Escobedo, N. Holt, L.J. Young, T.J. Brandeis. Spatial distribution and drivers of invasive woody plants in tropical urban ecosystems. Journal of Ecological Management In press.
*Becknell, J.M., A. Desai, M. Dietze, G. Starr, J. Franklin, J. Hall, A. Pourmokhtarian, P. Stoy, P. Duffy, M. Binford, C.L. Staudhammer. 2015. Assessing Interactions Among Changing Climate, Management, and Disturbance in Forests: A macrosystems approach. Bioscience 65 (3): 263–274.
*Malone, S.L., Staudhammer, C.L., Oberbauer, S.F., Olivas, P., Ryan, M.G., Schedlbauer, J., Loescher, H.W., Starr, G. 2014. El Niño Southern Oscillation (ENSO) enhances CO2 exchange rates in freshwater marsh ecosystems in the Florida Everglades. PlosOne. DOI: 10.1371/journal.pone.0115058.
Starr, G., C.L. Staudhammer, H.W. Loescher, R. Mitchell, A. Whelan, J. McGee, J.K. Hiers, J.J. O’Brien. 2014. Time series analysis of Forest Carbon Dynamics: Recovery of Pinus palustris following a Prescribed Fire. New Forest. DOI 10.1007/s11056-014-9447-3.
Starr, G., C.L. Staudhammer, H.W. Loescher, R. Mitchell, A. Whelan, J. McGee, J.K. Hiers, J.J. O’Brien. 2014. Time series analysis of Forest Carbon Dynamics: Initial Evidence of Resiliency in Longleaf Pine Ecosystem Physiological Estimates following a Prescribed Fire. Accepted to New Forest.
*Malone, S.L., Staudhammer, C.L., Loescher, H.W., Olivas, P., Oberbauer, S.F., Ryan, M.G., Schedlbauer, J., and Starr, G. 2014. Seasonal patterns in energy partitioning of two freshwater marsh ecosystems in the Florida Everglades. JGR Biogeosciences. doi: 10.1002/2014JG002700.
*Timilsina, N., F.J. Escobedo, C.L. Staudhammer, T.J. Brandeis. 2014. Analyzing causal factors of carbon stores in a subtropical urban forest. Ecological Complexity 20:23-32. DOI: 10.1016/j.ecocom.2014.07.001.
*Timilsina, N., C.L. Staudhammer, F.J. Escobedo, A.B. Lawrence*. 2014. Tree biomass, wood waste yield, and carbon storage changes in an urban forest. Landscape and Urban Planning 127:18-27. DOI: 10.1016/j.landurbplan.2014.04.003.
Kainer, K.A., L.H.O. Wadt, and C.L. Staudhammer. 2014. Testing a silvicultural recommendation: Brazil nut responses 10 years after liana cutting. Journal of Applied Ecology 51(3): 655-663. DOI: 10.1111/1365-2664.12231.
Rockwell, C., K. Kainer, C. Baraloto, and C.L. Staudhammer. 2014. Logging in bamboo-dominated forests in southwestern Amazonia: Caveats and opportunities for smallholder forest management. Forest Ecology and Management 315: 202–210.
Zeidemann, V., K.A. Kainer, and C.L. Staudhammer. 2013. Heterogeneity in NTFP quality, access and management shape benefit distribution in an Amazonian extractive reserve. Environmental Conservation doi:10.1017/S0376892913.
Tucker-Lima, J.M., C.L. Staudhammer, T. Brandeis, W. Zipperer, F. Escobedo. 2013. Growth and change in a subtropical urban forest in San Juan, Puerto Rico, 2001-2010. Landscape and Urban Planning DOI: 10.1016/j.landurbplan.2013.08.007.
*Malone, S., G. Starr, C. L. Staudhammer, and M. G. Ryan. 2013. Effects of simulated drought on the greenhouse carbon balance of Everglades short-hydroperiod marsh ecosystems. Global Change Biology DOI: 10.1111/gcb.12211.
*Timilsina, N. and C.L. Staudhammer. 2013. Individual tree-based diameter growth model of slash pine in Florida using non-linear mixed modeling. Forest Science 59(1): 27-37.
Staudhammer, C.L., L.H.O. Wadt, K.A. Kainer. 2013. Tradeoffs in diameter growth and reproduction shift over the lifetime of a long-lived tropical species. Oecologia DOI 10.1007/s00442-013-2603-1.
Whelan, A., R. Mitchell, C. L. Staudhammer, and G. Starr. 2013. The cyclic occurrence of fire and its role in carbon dynamics along an edaphic moisture gradient in longleaf pine ecosystems. PLoS ONE 8(1): e54045. doi:10.1371/journal.pone.0054045.
Genet, H., S.F. Oberbauer, S.J. Colby, C. Staudhammer, and G. Starr. 2013. Growth responses of Sphagnum hollows to a season lengthening manipulation in Alaskan arctic tundra. Polar Biology DOI 10.1007/s00300-012-1236-x.
*Timilsina, N. and C.L. Staudhammer. Individual tree mortality model for slash pine in Florida: a mixed modeling approach. 2012. Southern Journal of Applied Forestry 36(4): 211-219.
Jimenez, K.L., G. Starr, J. L. Schedlbauer, C. L. Staudhammer, H. W. Loescher, and S.F. Oberbauer. 2012. Carbon dioxide exchange rates from short- and long-hydroperiod everglades freshwater marsh. JGR-Biogeosciences 117, G04009, doi:10.1029/ 2012JG002117.
Klimas, C., K.A. Kainer, L.H. Wadt, C.L. Staudhammer, V. Rigamonte-Azevedo, Freire Correia, M.; and L.M. da Silva Lima. 2012. Control of seed production at multiple scales: a 5-year study exploring the influences of tree attributes, habitat heterogeneity, and climate cues. Journal of Tropical Ecology 28:105-118.
*Lawrence, A.B., F.J. Escobedo, C.L. Staudhammer, and W. Zipperer. 2012. Temporal changes and drivers of growth and mortality in a subtropical urban forest ecosystem. Landscape and Urban Planning 104:85-94.
Soriano, M., K.A. Kainer, C.L. Staudhammer, and E. Soriano. 2011. The growing dilemma of timber harvesting in Brazil-nut rich, community forests: effects on natural regeneration and forest disturbance. Forest Ecology and Management. In press. doi:10.1016/j.foreco.2011.05.010.
*Malone, S.L, L.N. Kobziar, C.L. Staudhammer, A. Abd-elrahman. 2011. Modeling relationships among 217 fires using remote sensing of burn severity in southern pine forests. Remote Sensing 3: 2005-2028; doi:10.3390/rs3092005.
Thompson, B.K., F.J. Escobedo, C.L. Staudhammer, C.J. Matyas, and Y. Qiu. 2011. Modeling hurricane-caused urban forest debris in Houston, Texas. Landscape and Urban Planning 101: 286–297.
Staudhammer, C.L., F.J. Escobedo, A.B. Lawrence, M. Duryea, P. Smith, and M. Merritt. 2011. Rapid Assessment of Change and Hurricane Impacts to Houston’s Urban Forest Structure. Arboriculture & Urban Forestry 37(2):60-66.
Lee, H., E.A.G. Schuur, J.G. Vogel, M. Lavoie, D. Bhadra, and C.L. Staudhammer. 2010. A Spatially explicit analysis to model carbon fluxes at a larger scale in upland tundra where permafrost is thawing. Global Change Biology 17(3): 1379-1393.
Zhao, M., C.L. Staudhammer, and F. Escobedo. 2010. Composition and structure of public and private urban forests in subtropical Miami-Dade County, USA. Urban Forestry & Urban Greening 9(3), doi:10.1016/j.ufug.2010.01.008.
Staudhammer, C.L., F. Escobedo, C. Luley, and J. Bond. 2009. Patterns of urban forest debris from the 2004 and 2005 hurricane seasons in Florida. Southern Journal of Applied Forestry 33(4): 193-196.
Valle, D.R., C.L. Staudhammer, W. Cropper, and P. Van Gardingen. 2009. The importance of multimodel projections to assess uncertainty in projections from simulation models. Ecological Applications 19(7): 1680-1692.
Escobedo, F., C. Luley, J. Bond, C.L. Staudhammer, and C. Bartel. 2009. Hurricane debris and damage assessment for Florida urban forests. Arboriculture & Urban Forestry 35(2): 100-106.
Staudhammer, C.L., E.J. Jokela, and T.A. Martin. 2009. Competition dynamics in pure- versus mixed-family stands of loblolly and slash pine in the southeastern United States. Canadian Journal of Forest Research 39(2): 396-409.
Wadt, L. H. O., K. A. Kainer, C.L. Staudhammer, and R.O. Peréa Serrano. 2008. Sustainable forest use in Brazilian extractive reserves: natural regeneration of Brazil nut in exploited populations. Biological Conservation 141(1): 332-346.
Kozak, A., R.A. Kozak, C.L. Staudhammer, and S. Watts. 2008. Introductory Probability and Statistics: Applications for Forestry and Natural Sciences. CABI, Wallingford, UK. 448 Pp.
Valle, D.R., C.L. Staudhammer, and W. Cropper. 2007. Simulating multiple use forest management: How to integrate the simulation of Non-Timber Forest Product (NTFP) extraction to the simulation of timber extraction in tropical mixed forests? Journal of Forestry 105(6): 301-306.
Kainer, K. A., L.H. Wadt, and C.L. Staudhammer. 2007. Explaining variation in Brazil nut fruit production. Forest Ecology and Management 250(3):244-255.