People (Join us!)
Erin R. Hotchkiss (she/her)
Associate Professor, Department of Biological Sciences | Faculty Affiliate, Global Change Center | Virginia Tech
Office: Derring Hall 2006B | Phone: +1 540-231-7005 | email: ehotchkiss[at]vt.edu
Google Scholar | ORCID | @FluvialBenthos on bluesky, twitter | ResearchGate | LinkedIn | Wiki | Curriculum Vitae
I am an ecologist who uses empirical data and statistical models to understand how environmental change, land-water interactions, and ecosystem processes shape the transport, transformation, and fate of carbon and nutrients in freshwaters. Questions of interest include: How, when, and where do biological processes regulate carbon and nutrient export and emission fluxes at the ecosystem and meta-ecosystem scale? In what ways do climate and landscape changes alter freshwater biogeochemistry, metabolism, and food webs? What is the function and fate of algal and terrestrial organic matter in river networks? I use a combination of monitoring, experimental, and quantitative approaches to study freshwater ecosystems.
GRADUATE STUDENTS
Michael Beall
Ph.D. Student | Department of Biological Sciences | Virginia Tech
mcb2370[at]vt.edu
Stream function plays a pivotal role in maintaining environmental balance. As landscapes evolve, streams encounter exogenous disturbances that degrade water quality, impacting ecosystems and potable water sources. I aim to deepen my understanding of how these changing landscapes influence the metabolic processes of streams, with a particular focus on carbon dynamics in response to heterogeneous landscapes during flow disturbance events.
Caleigh Meehan
M.Sc. Student | Department of Biological Sciences | Virginia Tech
LinkedIn | cemeehan[at]vt.edu
I’m interested in how landscape changes and anthropogenic inputs impact metabolism, nutrient cycling, and food web dynamics. In the past, I have been able to study gas flux (specifically methane and carbon dioxide) in temporary ponds and the impact of sedimentation on stream metabolism. I’m currently studying salinization in headwater streams impacted by mining practices and its impact on ecosystem metabolism. I hope to connect this with food web dynamics through collaboration with other project members.
Carla López Lloreda
Ph.D. Candidate | National Science Foundation Graduate Research Fellow | Department of Biological Sciences | Interfaces of Global Change Program | Virginia Tech
@carlalopezpr | LinkedIn | carlalopez[at]vt.edu
I am interested in how freshwater ecosystems process and transport nutrients and solutes across the landscape and how these processes can be different or possibly fundamentally altered after extreme climatic events such as hurricanes and droughts. I have a particular interest in understanding these processes in places that might be more vulnerable to climate change, like tropical islands or coastal ecosystems, with the ultimate goal of understanding the future of our water resources.
Katherine X. Pérez Rivera
Ph.D. Student | Fulbright Research Fellow | Department of Biological Sciences | Future Professoriate Program | Virginia Tech
ResearchGate | kperezrivera[at]vt.edu
I am interested in understanding dissolved organic matter and nutrient cycling, transport, processing and exchange in freshwater ecosystems, and how this is influenced by inputs from the surrounding landscape. I am also interested in how water quality changes along river networks as a result of landscape disturbances and determining the drivers that influence the response of aquatic ecosystems to in-stream processing of terrestrial inputs and microbial activity.
RESEARCH ASSOCIATES
Frances Iannucci, M.Sc.
Stream Team Analytical Laboratory Manager & Data Scientist | Virginia Tech
My interests center on how aquatic ecosystem structure and function are shifting in the face of climate change, with the goal of considering ecosystem processes from a holistic perspective. Much of my recent research has focused on the response of stream chemistry and metabolism to permafrost thaw in Arctic and boreal ecosystems. For my Master's thesis and as a data scientist prior to starting my current position, I studied stream carbon cycling at sites across the United States as part of an effort to link aquatic and terrestrial carbon cycles.
UNDERGRADUATE RESEARCHERS
Brooke Vaughn
Biological Sciences | Virginia Tech
Undergraduate Research:
Local Waterways Research Team: Changes in downstream water quality & ecosystem health after a pond sediment removal project (2024-present)
Erin Walters
Biological Sciences | Virginia Tech
Undergraduate Research:
Local Waterways Research Team: Changes in downstream water quality & ecosystem health after a pond sediment removal project (2024-present)
Carter Offhaus
Biological Sciences | Virginia Tech
Undergraduate Research:
Local Waterways Research Team: Changes in downstream water quality & ecosystem health after a pond sediment removal project (2024-present)
Andie Flota
Water: Resources, Policy, and Management | Virginia Tech
Undergraduate Research:
Local Waterways Research Team: Changes in downstream water quality & ecosystem health after a pond sediment removal project (2024-present)
Jialin Huo
Biological Sciences | Virginia Tech
Undergraduate Research:
Local Waterways Research Team: Changes in downstream water quality & ecosystem health after a pond sediment removal project (2024-present)
Katherine Campo
Water: Resources, Policy, and Management | Virginia Tech
Undergraduate Research:
Local Waterways Research Team: Changes in downstream water quality & ecosystem health after a pond sediment removal project (2024-present)
Emma Lucier
Biological Sciences | Virginia Tech
Undergraduate Research:
Local Waterways Research Team: Changes in downstream water quality & ecosystem health after a pond sediment removal project (2024-present)
ALUMNI
Graduate Students
Stephen Plont
Ph.D., Biological Sciences | Interfaces of Global Change Fellow | National Science Foundation Graduate Research Fellow | Virginia Tech | 2023
Dissertation: Moving beyond the stream reach: Assessing how confluences alter ecosystem function and water quality in freshwater networks
Currently: Postdoctoral Fellow, Department of Biological Sciences, University of Alabama
Kristen Bretz
Ph.D., Biological Sciences | Interfaces of Global Change Fellow | Virginia Tech | 2023
Dissertation: Headwater stream network connectivity: Biogeochemical consequences and carbon fate
@ka_bretz | ResearchGate | website | kabretz[at]vt.edu
Currently: Instructor, Department of Biological Sciences, Virginia Tech
Mohammed Hamdan
Ph.D., Ecology | Umeå University, Sweden | 2021
Dissertation: Effects of temperature and terrestrial carbon on primary production in lake ecosystems
Co-supervised by Jan Karlsson, Pär Byström, & Erin Hotchkiss
Currently: Instructor & Researcher, University of Baghdad, Iraq
Brynn O'Donnell
M.Sc., Biological Sciences | Virginia Tech | 2019
Thesis: The flow regime of function: Influence of flow changes on biogeochemical processes in streams
Currently: Social Impact Program Manager, Filecoin Foundation
Marie Gérardin
M.Sc., Biology | Université du Québec à Montréal, Canada | 2019
Thesis: Sources et facteurs menant à la sursaturation en CO2 et CH4 des rivieres boreales
Primary supervisor: Paul del Giorgio; Additional mentors: Erin Hotchkiss & Joan P Casas Ruiz
Currently: Water and Sanitation Service Management Assistant (Assistante de Gestion Service Eau et Assainissement), Saint-Dié-des-Vosges, France
Emelie Landström
M.Sc., Ecology | Umeå University, Sweden | 2015
Thesis: Resource use by macro-invertebrates within boreal stream food webs
Primary supervisor: Jan Karlsson; Additional mentors: Erin Hotchkiss & Ryan Sponseller
Currently: Environmental Officer, Examination of Environmental Hazardous Activities (Miljöhandläggare prövning miljöfarlig verksamhet), Västerbotten County Administrative Board, Sweden
Postdoctoral Fellows
Sarah Ellen Johnston (she/her)
National Science Foundation (NSF) Earth Sciences Postdoctoral Fellow | 2021-2022
Research topic: Organic carbon transformations from a mountain to grassland transitional river network in Southern Alberta, Canada
Mentors: Matthew Bogard (University of Lethbridge) & Erin Hotchkiss (Virginia Tech)
Position after this postdoc: Assistant Professor, Department of Chemistry and Biochemistry, University of Alaska Fairbanks
Kelly Hondula
Postdoctoral Fellow | National Ecological Observatory Network (NEON) | 2021-2022
Research topic: Using remote sensing data to characterize aquatic ecosystems at broad scales
Mentors: Robert Hensley (NEON), Mirela Tulbure (North Carolina State University), & Erin Hotchkiss (Virginia Tech)
Position after this postdoc: Postdoctoral Research Scholar, Arizona State University
Undergraduate and Postgraduate Researchers, Virginia Tech
Emily Mulcahy
Biological Sciences, Wetland Science, & Green Engineering | Virginia Tech
Undergraduate Research:
Linking oxygen and carbon biogeochemistry with primary production in headwater wetlands (2023-2024)
2024 Global Change Center Grant Awardee
VT 2024
Evie Dana
Biological Sciences | Virginia Tech
Undergraduate Research:
Linking stream resources with food webs across biomes: Characterizing primary producer and macro-invertebrate communities (2023-2024)
Allyson Kaelin
Biological Sciences | Virginia Tech
Undergraduate Research:
Linking stream resources with food webs across biomes: Integrating water chemistry with resource availability in streams (2023-2024)
VT 2024
Tiffany Meadows
Biological Sciences | Virginia Tech
Undergraduate Research:
Linking stream resources with food webs across biomes: Aquatic & terrestrial organic matter quality (2023-2024)
Isabella Korobow
Biological Sciences | Virginia Tech
Undergraduate Research:
Linking stream resources with food webs across biomes: Macro-invertebrate functions & food web structure (2023-2024)
Peyton Rowe
Environmental Science | Virginia Tech
Undergraduate Research:
Linking stream resources with food webs across biomes: Macro-invertebrate richness & food web roles (2023-2024)
Caroline Brickner
Biological Sciences | Virginia Tech
Undergraduate Research:
Linking stream resources with food webs across biomes: Dissolved organic matter dynamics (2023-2024)
VT 2024
Sarah Masters
Environmental Science | Virginia Tech
Undergraduate Research:
Linking stream resources with food webs across biomes: Stream chlorophyll dynamics (2023-2024)
Jared Rasmussen
Fish Conservation | Virginia Tech
Undergraduate Research:
Linking stream resources with food webs across biomes: Fish communities & food web structure (2023-2024)
Cleo Orlando
Microbiology & Chemistry | Virginia Tech
Undergraduate Research:
Exploring nutrient cycling and microbial activity in retention ponds and surrounding waterways (2023)
2023 Fralin Summer Undergraduate Research Fellowship (SURF) Awardee
VT 2024
Gavriel Cambridge
Biological Systems Engineering | Virginia Tech
Undergraduate Research:
Changing hydrologic connections and carbon emissions across beaver-influenced stream corridors & headwater wetlands (2021-2023)
2022 Virginia Water Resources Research Center Student Research Grant Awardee
VT 2024
Carmen Curry
Environmental Science & Ecological Restoration | Virginia Tech
Undergraduate Research:
Drying-rewetting dynamics in a non-perennial forested stream (2023)
VT 2024
Sarah Mitchener
Biological Sciences | Virginia Tech
Undergraduate Research:
Stream ecology and water quality patterns in different eco-regions of the United States (2021-2022)
VT 2023
Natalie Murphy
Biochemistry | Virginia Tech
Undergraduate Research:
Spatial patterns of intermittency and microbial metabolism in mining-impacted and reference streams (2019-2022)
2021 Global Change Center Grant Awardee
VT 2022
Felicity deToll
Environmental Sciences | Virginia Tech
Undergraduate Research:
Connecting carbon cycling with nutrient loads in wetlands (2021)
2021 Fralin Summer Undergraduate Research Fellowship (SURF) Awardee
VT 2022
Morgan Wood
Environmental Informatics | Virginia Tech
Undergraduate Research:
Microbial metabolism in fluvial networks (2021)
VT 2021
Kelly Crum
Water: Resources, Policy, and Management | Virginia Tech
Undergraduate Research:
Biological controls on water quality in intermittent and warming headwater streams (2021)
VT 2021
Lauren Morris
Biological Sciences & Green Engineering | Virginia Tech
Undergraduate Research:
Ecological applications of high-frequency data and ecosystem metabolism estimates (2020-2021)
VT 2022
Bryce Onozuka
Biological Sciences & Economics | Virginia Tech
Undergraduate Research:
Global patterns of photosynthesis and respiration in running waters (2020-2021)
VT 2021
Cameron Braswell
Biological Sciences | Virginia Tech
Undergraduate Research:
Carbon metabolism in streams and rivers: Confluence- to global-scale assessments (2019-2021)
VT 2021
Alexis "AJ" Jackson
Biological Sciences | Virginia Tech
Undergraduate Research:
Carbon emissions from riparian wetlands (2019-2020)
2019 NSF REU Fellow; 2020 Global Change Center Grant Awardee; 2020 SFS Instars Fellow; 2020 Virginia Tech Undergraduate Research Excellence Awardee; & 2021 NSF GRFP Awardee
VT 2020
Jonathon "Jack" Monroe
Biological Sciences, Microbiology, & Chemistry | Virginia Tech
Undergraduate Research:
Microbial metabolic fingerprints in intermittent headwater streams (2019-2020)
2019 Global Change Center Grant Awardee & 2019-2020 Robert Jones Undergraduate Research Excellence Awardee
VT 2020
Jake Riney
Computer Science & Biological Sciences | Virginia Tech
Undergraduate Research:
Ecosystem metabolism at stream confluences (2019-2020)
VT 2020
Shawn Becker
Science Teacher | Gate City High School
NSF RET Fellow:
Rapid assessment of ecosystem respiration in streams and rivers (2019)
Jacob Beckner
Fish Conservation | Virginia Tech
Undergraduate Ecology Research & Teaching:
Freshwater ecology, species invasions, and meta-ecosystem food webs (2019)
VT 2020
Sumaiya Rahman
Biological Sciences | Virginia Tech
Undergraduate Research:
Influence of storm magnitude on dissolved oxygen in streams (2018); Greenhouse gas emissions from terrestrial-aquatic interfaces and temporary waterways (2018-2019)
2018 NSF REU Fellow
VT 2019
Caitlin (Miller) Hemphill
Wildlife Conservation, Biological Sciences, & Wetland Science | Virginia Tech
Undergraduate Research:
Stream confluence dissolved organic matter dynamics (2018-2019)
VT 2019
Melissa Castillo
Pre-Health Sciences | Salt Lake Community College
Undergraduate Research:
Organic matter sources and carbon metabolism in streams (2018)
2018 MAOP Research Fellow
Schuyler van Montfrans
Teacher | Decatur High School
NSF RET Fellow:
Temporal variability in carbon and nutrient demands in a dynamic urban stream (2018)
Quentin Pitts
Biological Sciences | Virginia Tech
Undergraduate Research:
How does stream salinization alter dissolved organic matter dynamics? (2018)
VT 2018
Visiting Researchers, Virginia Tech
Victoria Julieta García
Visiting Postdoctoral Research Fellow (2018)
Centro Austral de Investigaciones Científicas, Argentina
Undergraduate Biological Sciences Field Study, Virginia Tech
2023: Hiya Barai & Emily Mulcahy
2020: Lauren Morris & Bryce Onozuka
2019: Cameron Braswell & Natalie Murphy
2018: Emily Byrd, Jack Monroe, Hank Liu, & Caitlin Miller
2017: Sumaiya Rahman, Quentin Pitts, & Jonathan Cordle
Undergraduate and Postgraduate Researchers, University of Wyoming
Paige Hellbaum (2012-2013), Jessica Neuwerth (2012-2013), Amy Saville Rhoad (2011-2013), Noah Berg-Mattson (2011-2012), Clark Johnson (2011-2012), Sarah Gregory (2010-2011), Trista Niekum Coble (2009-2011), Sahale Casebolt (2009), Brenna Hansen (2008-2009), Tamara Lehnertz Bretting (2007-2008), Elias Anoszko (2007), & Joshua Theurer (2007)
