Community and Ecosystem Ecology Group

	The Community and Ecosystem Genetics Group The University of Tennessee

People	Projects	Publications	Broad Impacts and Outreach	Prospective Students	Facilities

Jen Schweitzer

Ph.D., 2002, Northern Arizona University

Jen.Schweitzer"at"utk.edu

Phone: 865-974-0856

Using a combination of field research and experimental manipulations our lab has been focused on the ecological and evolutionary links between above- and below-ground processes in forest ecosystems. We take an integrative community and ecosystems genetics approach to understanding the ecosystem consequences of species interactions. With this approach we are interested in broadly addressing questions regarding the importance of biodiversity and genetic diversity, plant-animal interactions and invasive species to ecosystem ecology.

Joe Bailey

Ph.D., 2003, Northern Arizona University

Phone: 865-974-0864

Joe.Bailey"at"utk.edu

I consider myself to be an evolutionary ecologist broadly interested in how species interactions link genes and ecosystems, how natural selection operates in a community context, and how these processes scale geographically and with genetic resolution (i.e., small molecular differences to subpopulation structure). I try to take an integrative view of natural systems and have worked with native and introduced plants and herbivores, from microbes to mammals, linking genes to ecosystems.

Stacy Martinez

Laboratory Coordinator

I am from the Central Coast, Australia, which is approximately one hour north of Sydney. I moved to the United States in early 2008 and am enjoying living in Knoxville. I have a Bachelors degree in Environmental Science from the University of Newcastle, Australia. I am interested in many aspects of environmental science including; invasive species, and soil chemistry and its relationship to its surrounding environment.

I am the Research Coordinator of the Community and Ecosystems Laboratory, which basically means I help organize the everyday operation of the lab, which varies from organizing and assisting graduates with the laboratory aspect of their research, training students in general lab procedures, through to keeping the lab stocked and ready for more! In my spare time I enjoy reading, hiking, and good food!

Clara Pregitzer

I am generally interested in plant-soil feedbacks and the evolutionary consequences of these interactions. My research focuses on genetic by environment interactions and how different genotypes of Populus angustifolia influence nitrogen cycling and soil microbial communities within three common gardens across an elevational gradient. Understanding how this genotype by environment interaction affects ecosystem processes has important evolutionary and applied ecological consequences. Once the soil is conditioned by this dominant tree (through leaf litter and root exudates) it effects the survival and performance of its offspring. Currently, I am trying to quantify how this relationship can influence seedling growth through selection of trait variation and survival. These legacy affects of plant soil feedbacks could potentially shape the riparian forests of the west, and conservation of genetic diversity in these areas will extend to increase the diversity and structure of this important ecosystem. I am also interested using genetic and evolutionary knowledge in applied ecology and ecological restoration. In my spare time I enjoy eating tacos, nature, taking pictures of nature, yoga, live music and spending time with my dog and friends.

Mark Genung

I am an ecologist with broad interests including community and ecosystem genetics, quantitative methods in ecology, and the importance of genotypic and species diversity to community and ecosystem properties.

Research: Although it is well known that genotypic and species diversity can be important to community and ecosystem properties, I am interested in finding patterns that can help predict when genotypic and species diversity may be more, or less, important. I am also interested in investigating the role that adaptive evolution plays in determining traits with important community and ecosystem level consequences; in other words, putting evolution in a community and ecosystem context.
To address these questions, I use two common gardens which manipulate genotypic and species diversity in Solidago, and I am in the process of establishing a third common garden using individuals of Solidago collected along a 1000 m elevational gradient in the southern Appalachians. This garden will examine local adaptation to changing conditions along an elevational gradient. Additionally, I will manipulate Solidago genotypic diversity at each elevation, to test whether genotypic diversity is more or less important at different elevations.

Contact: My email address is mgenung @ utk.edu, and please feel free to contact me if you have any questions, or if you have similar interests and just want to talk about ecology!

Emmi Felker-Quinn

Emmi graduated from Smith College in 2006 with a B.A. in Biology. Her undergraduate thesis focused on the historic presence of introduced plant species in Western Massachusetts. Since June 2006, Emmi has been working as a lab technician for Richard Norby and Aimee Classen at the Oak Ridge National Lab’s FACE and OCCAM sites.

Brett Ashenfelter

I am interested in ethnobotany. I am currently working on classifying various Argentinean botanicals based on how humans have used them. In the future, I would like to work on a system for quantitatively
analyzing the uses of these plants.

Nicole Hergott

NSF-REU Undergraduate Research

I am interested in genetic variation of mycorrhizal associations. More specifically, I am interested in examining the trade-offs of ectomycorrhizal and arbuscular mycorrhizal colonization of Cottonwood and how genotypes might mediate this interaction. This summer I will be visiting Northern Arizona University to learn some of the morphological and molecular techniques for assessing ectomycorrhizal and arbuscular mycorrhizal colonization in Cottonwood. In my free time I enjoy water tubing, canoeing and spending time with my family at Dollywood.

Derek Dawson

Emily Giles

Undergraduate Research

I am interested in the microanalysis of organismal interactions and how these interactions influence community and ecosystem dynamics. I am predominantly interested in factors affecting nutrient cycling dynamics including the relationship between above ground and below ground processes. I am currently researching the “after-dead” affects of herbivory on decomposition rates, and this summer I will be analyzing soil microbial distributions. In the future, I hope to expand my knowledge of community genetics and its role in ecosystem function.

Michelle Stritar

Undergraduate Research

Michelle's research focused on how an introduced herbivore (elk) alter soil nutrient availability, microbial community dynamics and enzyme function across an 18 year fire chronosequence in aspen forests of Northern Arizona. Michelle found that in the presence of elk it would take nearly 20 additional years to restore soil dynamics in aspen forests to conditions that were observed in the absence of elk. This manuscript is currently being developed for submission to Ecology.

	Jen Schweitzer Ph.D., 2002, Northern Arizona University Jen.Schweitzer"at"utk.edu Phone: 865-974-0856 Using a combination of field research and experimental manipulations our lab has been focused on the ecological and evolutionary links between above- and below-ground processes in forest ecosystems. We take an integrative community and ecosystems genetics approach to understanding the ecosystem consequences of species interactions. With this approach we are interested in broadly addressing questions regarding the importance of biodiversity and genetic diversity, plant-animal interactions and invasive species to ecosystem ecology.
	Joe Bailey Ph.D., 2003, Northern Arizona University Phone: 865-974-0864 Joe.Bailey"at"utk.edu I consider myself to be an evolutionary ecologist broadly interested in how species interactions link genes and ecosystems, how natural selection operates in a community context, and how these processes scale geographically and with genetic resolution (i.e., small molecular differences to subpopulation structure). I try to take an integrative view of natural systems and have worked with native and introduced plants and herbivores, from microbes to mammals, linking genes to ecosystems.
	Stacy Martinez Laboratory Coordinator I am from the Central Coast, Australia, which is approximately one hour north of Sydney. I moved to the United States in early 2008 and am enjoying living in Knoxville. I have a Bachelors degree in Environmental Science from the University of Newcastle, Australia. I am interested in many aspects of environmental science including; invasive species, and soil chemistry and its relationship to its surrounding environment. I am the Research Coordinator of the Community and Ecosystems Laboratory, which basically means I help organize the everyday operation of the lab, which varies from organizing and assisting graduates with the laboratory aspect of their research, training students in general lab procedures, through to keeping the lab stocked and ready for more! In my spare time I enjoy reading, hiking, and good food!
	Clara Pregitzer I am generally interested in plant-soil feedbacks and the evolutionary consequences of these interactions. My research focuses on genetic by environment interactions and how different genotypes of Populus angustifolia influence nitrogen cycling and soil microbial communities within three common gardens across an elevational gradient. Understanding how this genotype by environment interaction affects ecosystem processes has important evolutionary and applied ecological consequences. Once the soil is conditioned by this dominant tree (through leaf litter and root exudates) it effects the survival and performance of its offspring. Currently, I am trying to quantify how this relationship can influence seedling growth through selection of trait variation and survival. These legacy affects of plant soil feedbacks could potentially shape the riparian forests of the west, and conservation of genetic diversity in these areas will extend to increase the diversity and structure of this important ecosystem. I am also interested using genetic and evolutionary knowledge in applied ecology and ecological restoration. In my spare time I enjoy eating tacos, nature, taking pictures of nature, yoga, live music and spending time with my dog and friends.
	Mark Genung I am an ecologist with broad interests including community and ecosystem genetics, quantitative methods in ecology, and the importance of genotypic and species diversity to community and ecosystem properties. Research: Although it is well known that genotypic and species diversity can be important to community and ecosystem properties, I am interested in finding patterns that can help predict when genotypic and species diversity may be more, or less, important. I am also interested in investigating the role that adaptive evolution plays in determining traits with important community and ecosystem level consequences; in other words, putting evolution in a community and ecosystem context. To address these questions, I use two common gardens which manipulate genotypic and species diversity in Solidago, and I am in the process of establishing a third common garden using individuals of Solidago collected along a 1000 m elevational gradient in the southern Appalachians. This garden will examine local adaptation to changing conditions along an elevational gradient. Additionally, I will manipulate Solidago genotypic diversity at each elevation, to test whether genotypic diversity is more or less important at different elevations. Contact: My email address is mgenung @ utk.edu, and please feel free to contact me if you have any questions, or if you have similar interests and just want to talk about ecology!
	Emmi Felker-Quinn Emmi graduated from Smith College in 2006 with a B.A. in Biology. Her undergraduate thesis focused on the historic presence of introduced plant species in Western Massachusetts. Since June 2006, Emmi has been working as a lab technician for Richard Norby and Aimee Classen at the Oak Ridge National Lab’s FACE and OCCAM sites.
	Brett Ashenfelter I am interested in ethnobotany. I am currently working on classifying various Argentinean botanicals based on how humans have used them. In the future, I would like to work on a system for quantitatively analyzing the uses of these plants.
	Nicole Hergott NSF-REU Undergraduate Research I am interested in genetic variation of mycorrhizal associations. More specifically, I am interested in examining the trade-offs of ectomycorrhizal and arbuscular mycorrhizal colonization of Cottonwood and how genotypes might mediate this interaction. This summer I will be visiting Northern Arizona University to learn some of the morphological and molecular techniques for assessing ectomycorrhizal and arbuscular mycorrhizal colonization in Cottonwood. In my free time I enjoy water tubing, canoeing and spending time with my family at Dollywood.

	Derek Dawson
	Emily Giles Undergraduate Research I am interested in the microanalysis of organismal interactions and how these interactions influence community and ecosystem dynamics. I am predominantly interested in factors affecting nutrient cycling dynamics including the relationship between above ground and below ground processes. I am currently researching the “after-dead” affects of herbivory on decomposition rates, and this summer I will be analyzing soil microbial distributions. In the future, I hope to expand my knowledge of community genetics and its role in ecosystem function.
	Michelle Stritar Undergraduate Research Michelle's research focused on how an introduced herbivore (elk) alter soil nutrient availability, microbial community dynamics and enzyme function across an 18 year fire chronosequence in aspen forests of Northern Arizona. Michelle found that in the presence of elk it would take nearly 20 additional years to restore soil dynamics in aspen forests to conditions that were observed in the absence of elk. This manuscript is currently being developed for submission to Ecology.