Ph.D. 2010, Ecology & Evolution, Rutgers University
M.S. 2009, Statistics, Rutgers University
B.A. 2002, Biology & Environmental Studies, Dordt College
I have several lines of active research which fall under 3 broad categories: ecosystem-level effects of agricultural management practices, wetland plant invasions, and meta-analysis of existing ecological data.
· First, I am conducting research on carbon and nitrogen cycles in soils impacted by different biofuels production systems. This work is being done in collaboration with the EPSCoR researchers here at UNI and at ISU and UI. I am also working with Practical Farmers of Iowa (PFI, a nonprofit organization) and its members to determine the impacts of cover-cropping on soil carbon storage and retention.
· Second, I am using a simulation model to understand how different techniques of managing wetland invasive plants (burning, mowing, and herbicide application) affects ecosystem-level processes like carbon and nitrogen cycling. I am the PI on a grant to develop this model in collaboration with Jason Martina and Bill Currie (University of Michigan). We are seeking funding t to extend this work to a much larger scale, and apply our model to large portions of the Great Lakes Basin and the High Plains region.
· Finally, I employ advanced statistical techniques for meta-analysis in order to provide new insights from existing ecological data. I have two current projects running under this main thread. The first is an effort to understand the frequency of statistical Type I errors (false rejection of the null hypothesis) in the ecological literature. The second project is a re-analysis of data on the total amount of bird and mammal predation stemming from feral and domestic cats (Felis catus). For this project I have constructed a Bayesian hierarchical model which my colleagues from Rutgers University, Ohio Dominican University, and Penn State will parameterize using existing data from the literature.
Currie, W.S., D.E. Goldberg, J. Martina, R. Wildova, E. Farrer, and K.J. Elgersma (2014). Emergence of nutrient-cycling feedbacks related to plant size and invasion success in a wetland community–ecosystem model. Ecological Modelling 282: 69-82.
Elgersma, K.J. (2014) Soils Suppressing and Promoting Non-native Plant Invasions. In: Interactions in Soil: Promoting Plant Growth. Springer.
Elgersma, K.J., S. Yu, T. Vor, and J.G. Ehrenfeld (2012). Microbial-mediated feedbacks of leaf litter on invasive plant growth and interspecific competition. Plant & Soil 356(1-2): 341-355.
Elgersma, K.J., Ehrenfeld, J.G., Yu, S., and Vor, T. (2011). Legacy effects overwhelm the short-term effects of exotic plant invasion and restoration on soil microbial community structure, enzyme activities, and nitrogen cycling. Oecologia 167(3): 733-745.
Foxman, B., K.J. Elgersma, A. Wen, M. Buxton, L. Zhang, and C. Barbosa-Cesnik (2011). Reply to Eells et al. Daily Cranberry Prophylaxis to Prevent Recurrent Urinary Tract Infections May Be Beneficial in Some Populations of Women. Clinical Infectious Diseases 52: 1394-1395. (with erratum published in Clin Infect Dis 54(2): 309)
Elgersma, K.J. and J.G. Ehrenfeld (2011). Linear and non-linear impacts of a non-native plant invasion on soil microbial community structure and function. Biological Invasions 13: 757-768.
Ehrenfeld, J.G., B. Ravit, and K. Elgersma (2005). Feedback in the plant-soil system. Annual Review of Environment and Resources 30: 75-115.