What We Do

Our lab investigates how plants and soil microbes mediate energy flow and nutrient dynamics in forests. Plants and microbes perform vital ecosystem services (e.g., carbon storage, water filtration, nutrient retention), and reduce the impacts of some of society’s greatest environmental threats. We use a complementary suite of approaches that integrate field observations with controlled environmental systems to address questions that intersect plant physiological ecology and soil microbial ecology in an ecosystem context.


Much of our work focuses in the role of roots, "the hidden half" of plants. Roots are often considered to be passive portals for soil resources. However, there is an emerging view that roots, through their activities and interactions with soil microbes, actively alter ecosystem processes. The consequences of root-microbe interactions are critical, as these processes link the carbon, nutrient, and water cycles in ecosystems, and have the potential to influence ecosystem dynamics and global climate change.

Three major themes of our research include:

  1. The impacts of belowground processes on carbon and nutrient dynamics across spatial scales

  2. Mycorrhizal associations as trait integrators for biogeochemical cycling in forests

  3. The role of plant and microbial interactions in mediating ecosystem reponses to global change (e.g., warming, drought, rising CO2, N deposition) .

Research Projects

The mycorrhizal associated nutrient economy: We're investigating how the traits of trees and their associated microbes influence biogeochemical processes in forests. We hypothesize that trees that associate with arbuscular mycorrhizal (AM) fungi alter nutrient and carbon cycling differently than trees that associate with ectomycorrhizal (ECM) fungi. We refer to this as the Mycorrhizal-Associated Nutrient Economy framework, and have been investigating whether AM and ECM trees contribute to unique “biogeochemical syndromes” in terms of energy transformations and nutrient cycling.

Drought impacts on carbon dynamics: Many climate models predict increases in the frequency and intensity of droughts in temperate biomes. Droughts reduce carbon uptake by vegetation, and thus reduce the potential of forests to slow climate warming. Droughts are also likely to impact soil microbes, which control nutrient availability and greenhouse gas fluxes. Our group is investigating the carbon consequences of drought in forests, and the degree to which species-specific adaptations to water stress (trees and soil microbes) influence the magnitude of this effect.

Biogeochemical impacts of understory invaders: Biological invasions are known to have highly variable impacts on ecosystem processes. We’re investigating the biogeochemical impacts of one of the most widespread invasive plant species in the eastern US, Microstegium vimineum (Japanese stiltgrass), in order to develop a framework to explain how and why invasion impacts differ across the landscape. Specifically, we’re examining whether species have the largest impacts where they are in greatest abundance, or where they function most differently from the resident vegetation with respect to nutrient cycling.

Plant-microbial feedbacks to global change: Forests slow global climate change by absorbing and storing CO2, but the extent to which these ecosystems will persist as carbon sinks is unknown. We are currently investigating the mechanisms by which trees and soil microbes mediate carbon retention and loss in forests. Specifically, we’re testing the hypothesis that roots play a critical role in stimulating microbes to release nutrients from soil organic matter - a process that increases plant growth, alters long-term soil carbon storage, and potentially affects feedbacks to climate.

Volatile organic carbon fluxes from soil: We are investigating the biotic and abiotic controls of volatile organic compound (VOC) emissions from forest soils. VOCs emitted from forests contribute significantly to the production of ozone in urban and regional environments, and represent the primary source of VOCs at the global scale. Aboveground plant tissues have long been considered the primary emitters of VOCs in forests, but recent studies suggest that roots and soil microbial emissions represent an important yet under-appreciated flux in these systems.

Climatic controls on carbon balance: We're investigating how intra- and inter-annual variation in climate influence carbon storage at the Morgan-Monroe State Forest. We're coupling micrometeorological (eddy co-variance) and ground-based approaches, including intensive measurements of belowground processes. Our research seeks to quantify and better understand 1) how much atmospheric CO2 is removed by forests, 2) what factors regulate productivity, and 3) how will the ability of the forest to store C respond to drought, warming, and rising atmospheric CO2?

Who We Are

Dr. Richard P. Phillips

Associate Professor
Director of Research, IU Research and Teaching Preserve
Department of Biology
247 Jordan Hall
1001 E. Third St.
Indiana University, Bloomington, IN 47405
(812) 856-0593

I was born in Boston, and graduated from the University of Vermont with a BA in Environmental Studies. After college, I landed a series of highly-rewarding teaching jobs: building hiking trails with at-risk youth, developing science and math lesson plans for special-needs students, and teaching first generation college-bound students through the Upward Bound Program. While I loved these experiences, I found myself longing to do science. So I enrolled in a masters program at the SUNY College of Environmental Science and Forestry, and conducted research on how aluminum toxicity (owing to acid rain) impacts sugar maple health. Eventually, I enrolled in a Ph.D. Program at Cornell where my dissertation focused on how trees enhance nutrient availability via the activities of their roots. After Cornell, I worked as a post-doc at Duke, investigating how trees exposed to CO2 enrichment physiologically adjust to take up soil nutrients and sustain productivity.
Mentorship is a critical component of a successful science career. As a mentor, I strive to make myself available and accessible, and I try to create a lab environment/culture where creativity is encouraged, excellence is expected and successes are celebrated. My mentoring philosophy is to provide mentees with (or help them find) all the tools and skills needed to conduct independent research and launch their own successful research programs. I try to lead by example by being enthusiastic, risk-taking and high-achieving in my scientific endeavors, and respectful and supportive in my professional interactions.
I welcome inquiries from motivated students interested in how regional and global environmental changes influence carbon and nutrient cycling in ecosystems. I strongly encourage you to read through a few recent lab publications. If you’re interested in the “big-picture” ideas described in the first few paragraphs of each paper’s Introduction, our lab is likely to be a good fit for you. Our lab is a collaborative, highly interactive and dynamic group, with broad interests in community/ecosystem ecology, and soil biogeochemistry. Incoming Ph.D. students are encouraged to develop their own research projects. Although not a prerequisite, prospective students with interests in fieldwork and familiarity with soils or plant tissue research are encouraged to apply.


Lab Members

Matt Craig
Ph.D student

Controls on soil organic matter formation and stabilization

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Steve Kannenberg
Ph.D student

Physiological responses of trees to drought

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Adrienne Keller
Ph.D student

Biogeochemical consequences of root-microbe interactions

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Katie Beidler
Ph.D student

Ecosystem consequences of root and fungal trait variation

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Andrea Scheibe

Tree species effects on soil biogeochemistry

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Loïc D'Orangeville

Climate change impacts on tree physiology

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Quan Zhang

Water, energy and carbon exchange between atmosphere and biosphere

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Laura Podzikowski
Lab manager/supervisor

Biogeochemical impacts of global change

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Technicians and undergraduate researchers

Robin Johnson

Dan Du

Mark Sheehan

Lab Alumni

Zach Brown (former lab supervisor; Ph.D. student at the University of Tasmania)
Eddie Brzostek (former post-doc; Assistant Professor at West Virginia University)
Alex Eilts (former visiting scientist; Research Associate at the University of Minnesota)
Luke Jacobs (former technician and undergraduate researcher; applying to Ecology Ph.D. programs)
Marissa Lee (former technician; Post-doc at George Washington University)
Ina Meier (former post-doc; now an Academic Assistant at the University of Göttingen, Germany)
Meghan Midgley (former Ph.D. student; Soil Scientist at Morton Arboretum, Chicago)
Andrew Quebbeman (former technician; Ph.D. student at Columbia University)
Anna Rosling (former visiting scientist; Associate Professor at Uppsala University, Sweden)
Ben Sulman (former post-doc; Research Scientist at the Geophysical Fluid Dynamics Lab, Princeton)
Amy Trowbridge (former post-doc; Assistant Professor at Montana State University)
Huajun Yin (former visiting scientist; Professor at Chengdu Institute of Biology, CAS)

Lab Life

Life in the Phillips Lab

Latest News

December, 2016: Busy year in 2016: Steve published his first chapter in Oecologia, Matt won best student talk in Biogeosciences at ESA, and is getting to submit two manuscripts, Adrienne completed her pulse labeling experiment, and is preparing her first manuscript, Andrea finished harvesting her massive mesocosms and is writing up the results, Quan and Loic are about to submit their first pd manuscripts, and Katie Beidler joined the lab.

Department of Biology
Jordan Hall Room 245
1001 E. Third St.
Indiana University, Bloomington, IN 47405
(812) 856-1563