Broad Research Interests
Urban and Suburban Ecology, Ecosystem Ecology, Soil Ecology, Restoration Ecology: Most of my research is focused on understanding how urban environments (the built environment, people) interact with the natural and semi-natural components of cities and suburbs. This provides an opportunity to explore the impacts of many of the same factors that are affecting biodiversity and ecosystem processes at the global scale. Examples include studying the effects of atmospheric nitrogen deposition, invasive species, habitat fragmentation, restoration management and socio-cultural legacies in affecting plant and soil communities and ecosystem processes. While my students and I perform manipulative, comparative and urban-rural gradient studies in park woodlands, riparian areas, highway verges, forested swamps, streams and residential areas, we also take a broader landscape ecology and ecosystem services approach to better address improving quality of life and human exchanges with nature in urban environments.
In addition to studies being conducted with my students, I have been involved for the past 4 years in an EPA-funded study in partnership with Louisville Olmsted Parks Conservancy to understand the impacts of invasive shrub honeysuckle and its removal by management on plant communities, soil processes and erosion in the woodlands of Cherokee Park.
I view education and outreach activities as a vital civic role for scientists, and am particularly interested in communicating scientific research findings to environmental managers, educators, and the public in order to improve our collective understanding of the value of natural “capital” and the contribution of nature’s ecological services to societal sustainability and resiliency to environmental perturbations.
Therefore, in addition to giving talks on the topics of invasive species, climate change and urban ecology to the public, I have also been involved in the following recent efforts:
I currently co-chair the Research and Inventory Committee of Louisville's Tree Board. Currently we are defining urban forest parameters that should be included for measurement in an Urban Forest Master Plan for the city.
I am also a science advisor for the Cherokee Triangle Neighborhood Tree Committee, who has completed their own Street Tree Inventory and is about to embark on a Residential yard inventory for their neighborhood.
I also co-chaired a subcommittee of the Louisville Climate Change Action Plan Task Force and wrote the Urban Forestry Section for the final report. This Report can be found online at APCD website: http://www.louisvilleky.gov/APCD/ClimateChange
Former Doctoral Students and Their Projects
Tara Trammell- Dissertation Title: The Forgotten Forest: Ecosystem Structure, Function, and Services of Forested Verges Along Interstates in Louisville, KY.
Tara focused her doctoral dissertation on understanding how soils and the structure and function of forests along urban interstate highway verges may differ along an urban-rural gradient. Her work focused on woody plant communities and how the legacy of construction disturbance on highway verge soils may affect soil carbon sequestration and current plant community composition. She has recently taken a Post-doctoral position at the University of Utah to continue her Urban Ecology research in Dr. Diane Pataki's laboratory.
Robert Johnson: Dissertation Title:Secondary Production in Urban Stream Food Webs: From Pattern to Process.
Robbie used the variation in nutrient inputs that exist along an urban-rural gradient of streams to study how bottom-up effects might affect macroinvertebrate community structure and the ecosystem process of secondary production by these important stream fauna. Robbie is currently a post-doctoral associate at the Carey Institute in Millbrook, NY and conducting research on urban streams at the NSF LTER site in Baltimore.
Jonathan White: Dissertation Title:Riparian Corridor Vegetation Structure and Soil Function Along Urban, Suburban and Rural Streams in Louisville, KY, USA.
Jonathan studied the impact of urbanization on riparian plant communities along an urban-rural gradient of streams. He also studied how greenhouse gas emissions and groundwater chemistry in riparian areas might be altered along an urban-rural gradient. Jonathan is currently teaching at a local college.
Allison Smith: Dissertation Research: Zooplankton in Freshwaters: Potential Responses to Global Warming, Nutrient Enrichment and Exotic Jellyfish.
Current Doctoral and Master's Students
Meghan Langley: Dissertation Research:Environmental correlates of woody plant composition, structure and invasion in bottomland hardwood forests
Meghan conducts her research in bottomland hardwood forests systems in the Louisville, Kentucky Metro Area. She is studying how the dominant native and non-native woody vegetation of these systems is shaped by various environmental gradients. These gradients include distance from forest edge, elevation, and light availability. She is also investigating the factors that facilitate or serve as barriers to invasion of these forested wetlands by exotic shrub honeysuckle.
Preston Pipal: Dissertation Research:Soil Microbial Biomass, Nutrient, and Earthworm Responses After Invasive Shrub Removal from Urban Woodland Parks
Stephen Bailey: Stephen has recently arrived in the lab and will be studying relationships between meiofauna and macrofauna in streams for his dissertation research.
Eli Levine: For his Master's degree Eli will be evaluating the effects of invasive honeysuckle shrub removal on forest plant communities in Cherokee Park woodlands.
Past Masters Degree Students
Wesley Daniel: Thesis Title: Impact of Urbanization on Fish Diversity, Composition and Structure of Stream Food Webs Along a Land-Cover Gradient in Jefferson County, Ky: Current and Historical Perspectives. Wes is currently a Post-doc at Michigan State University.
Amy Gentry: Thesis Title: Leaf Litter Decomposition as a Functional Assessment of a Natural Stream Channel Restoration Project. Amy currently works for an Environmental Consulting firm in the area.
Jay McLeod:Thesis Title: Quantitative Analysis of Tree Cover Distribution by Council District in Metro Louisville, KY. Jay recently graduate with a degree in Landscape Architecture from the University of Florida.
Shannon Scroggins: Thesis Title:Tree Community Composition, Abundance and Ecosystem Services in Residential Land and Relationships with Socio-demographics in Louisville, KY.
Matthew Vanderpool: Thesis Title:Suitability Analysis of Aedes albopictus, Culex pipiens and Aedes vexans based on Cultural, Built and Demographic Characteristics of Jefferson County, Ky. Matt currently works for the Dept. of Public Health in Louisville.
David Word: Thesis Title: Using Leaf Litter Breakdown to Assess the Effects of Mountaintop Removal Mining on Headwater Streams in Eastern Kentucky. David is currently the department chair of biology at a local private high school.