Kristen Bretz contributed a virtual talk in the "Non-perennial Streams: An Interface Between Hydrology, Ecology, Biogeochemistry, and Society" special session at the 2021 American Geophysical Union conference this week. Her talk shared new results from the final chapter of her dissertation, in which she is comparing water quality and metabolic consequences of stream fragmentation and reconnection in a pair of non-perennial mountain streams near Blacksburg, VA, USA:

Bretz, K.A., J.P. Gannon, & E.R. Hotchkiss. 2021. Metabolic patterns of non-perennial temperate forest streams. American Geophysical Union Conference. Virtual Talk.

Carla López Lloreda was part of a recent STEM outreach and education program, "Puerto Rico NEON Data Jam", where Carla and other professionals worked with 6 teachers and 50 students in Puerto Rico on projects using real-world scientific data from the National Ecological Observatory Network's (NEON) Guánica Dry Forest site to test research questions of interest to the students. Carla, her collaborators, and several of the students and instructors who were part of the project shared their experiences in this video: https://youtu.be/qDHKdHTyPOY

Katherine X. Pérez Rivera has been in the Czech Republic for over 3 months now as part of her Fulbright Research Grant. She is studying stream metabolism and collaborating with the Czech Geological Survey (CGS) on their over 30 year monitoring of small catchments in the Slavkov Forest, a place that is well-known for its mineral waters and contrasting lithology. She has been visiting field sites on a monthly basis to check on sensors and download data as well as assist with regular sampling. She will continue to work there until June 2022 and is excited about this collaboration with CGS and all the different experiences she is having as part of this educational and cultural exchange.

Check out the wonderful photos and annotations below from Katherine!

Erin recently returned from our final Coweeta field campaign of 2021! We're monitoring an experimentally warmed and a 2nd reference stream to test how increasing temperatures alter carbon fluxes, metabolism, and fate in headwater networks. This trip happened at the perfect time to appreciate the significance of annual leaffall inputs to Coweeta streams every autumn - the small streams were covered! This project is an NSF-funded collaboration with folks at University of Alabama, University of Georgia, Coastal Carolina University, and University of Connecticut.

Earlier this week, Erin Hotchkiss co-led a nature walk with Ignacio Moore (Professor, Biological Sciences) as part of our department's "Building Belonging in Biology" efforts led by Meg Emori (Instructor, Biological Sciences). We walked with undergraduate students from Derring Hall to Stroubles Creek and the Duck Pond while making observations and sharing knowledge about the environment around us. It was a great chance to connect/reconnect with students, facilitate in-person interactions among students and faculty beyond the classroom, and watch otters! A short video from our outing can be viewed here: https://vtx.vt.edu/videos/k/2021/11/1_vcigrvvo.html

Stephen Plont recently completed the second of two multi-week sampling campaigns throughout the Tom's Creek network in Blacksburg, VA. Plont is tracing the biogeochemical consequences of stream confluences as part of his dissertation research; data from October sampling will be compared with measurements from the same sites during summer 2021 to explore seasonal changes in water quality and ecosystem function. We're excited to see what we learn about metabolism and nutrient fluxes above/below confluences and throughout the fluvial network!

Kristen Bretz recently published the first chapter of her dissertation, "Integrating Ecosystem Patch Contributions to Stream Corridor Carbon Dioxide and Methane Fluxes" in the Journal of Geophysical Research - Biogeosciences! Kristen's paper was co-authored with three former undergraduate researchers in our lab, Alexis Jackson, Sumaiya Rahman, and Jonathon Monroe, as well as Erin Hotchkiss.

Summary: Carbon dioxide and methane emissions from freshwaters can be very different depending on where they are measured in a watershed. As distinct areas near a stream become connected by water moving through the watershed, stream greenhouse gas emissions may change in response to new carbon inputs from these connections. We found that CO₂ and CH₄ emissions were spatially variable within streams. CO₂ emissions were different between our two study summers while CH₄ emissions were more stable. We also found that the presence of vernal pool wetlands near a stream elevated total stream corridor carbon emissions.

Citation: Bretz, K.A., A.R. Jackson, S. Rahman, J.M. Monroe, & E.R. Hotchkiss. 2021. Integrating ecosystem patch contributions to stream corridor carbon dioxide and methane fluxes. Journal of Geophysical Research – Biogeosciences 126: e2021JG006313. https://doi.org/10.1029/2021JG006313.

Members of our research group contributed to several talks and posters at the 2021 Society for Freshwater Science (SFS) annual conference. We enjoyed opportunities to engage with other freshwater scientists across the globe on the virtual platform this year. We’re also looking forward to a hopefully in-person Joint Aquatic Sciences Meeting in 2022!

Presentations as lead authors or co-authors:

Lab members in bold; *=graduate student; **=undergraduate student

Bretz. K.A.*, N. Murphy**, & E.R. Hotchkiss. Stream fragmentation disrupts carbon emissions and transport. View talk.

Plont, S.*, J. Riney**, & E.R. Hotchkiss. Integrating perspectives on dissolved organic carbon removal and metabolism. View talk.

C. López Lloreda*, A. Herreid, & W.H. McDowell. The future of stream greenhouse gas dynamics in a stormier and drier tropical landscape.

Hotchkiss, E.R., C. Braswell**, K.A. Bretz*, A. Gray, C. López Lloreda*, L. Morris**, N. Murphy**, B. Onozuka**, K. Pérez Rivera*, & S. Plont*. A global assessment of organic carbon metabolism and spiraling in running waters. You can learn more about this collaboration (and contribute to our database!) at www.hotchkisslab.com/metab/MetabDB.

Hall, R.O., M.A. Baker, E.R. Hotchkiss, & S. Plont*. Modelling delayed respiration of labile DOC in a stream.

Tomczyk, N., A. Kaz, E.R. Hotchkiss, V. Gulis, J. Benstead, & A. Rosemond. Temperature effects on nutrient uptake in heterotrophic streams.

Cross, W., K. Anderson, A. Benke, T. Brey, E.R. Hotchkiss, A.D. Huryn, J. Jones, L. McGill, C. Patrick, P. Saffarinia, E. Scholl, M. Troia, J.B. Wallace, & M. Whiles. Investigating energetic scaling predictions for stream invertebrate communities.

James, A., E.R. Hotchkiss, D. McLaughlin, G. Pond, S. Schoenholtz, T. Timpano, C. Zipper, & S. Entrekin. Insect biomass and emergence sustained despite mayfly declines in mini-induced salinized Appalachian headwaters.

Other contributions to #2021SFS:

• Carla co-convened a special session, "Greenhouse gases in tropical streams, rivers, lakes and wetlands" (with primary convener N Marzolf and co-conveners D Riveros-Iregui, C Duvert, & M Ardón), and was a graduate student mentor in the Instars-Emerge program.

• Kristen hosted a virtual coffee break, “Show Me Your Pets!”, and co-organized the Student Resources Development Committee’s annual Student-Mentor Mixer.

• Stephen helped put together two pre-meeting workshops with the Student Resources Development Committee’s Undergraduate Affairs subcommittee to prepare undergraduate attendees for the virtual SFS meeting. Stephen also co-moderated the live discussion for presentations in “Hydroecology” with D Wynne.

• Erin co-convened two special sessions: (1) "Beyond lentic or lotic: Integrating the science of inland waters" (with primary convener M Fork and co-conveners J Gardner, S Jones, & C Solomon) & (2) "Exploring freshwater ecosystems under a changing climate via storm-driven nutrient, carbon, and sediment transport and biogeochemical cycling" (with primary conveners A Hounshell & SL Speir and co-conveners M Bieroza, J Hosen, & JL Tank). Erin also co-moderated the live discussion for presentations in “Lentic Ecology” and “Beyond lentic or lotic…” with R Brown.

Stephen Plont received an Outstanding Student Presentation Award for his virtual talk at the American Geophysical Union's (AGU) annual meeting in December 2020. His talk was titled "Mixing Downstream of Stream Confluences Alters Carbon and Nutrient Cycling in Freshwater Networks", and was given as part of a special AGU Hydrology session on "Frontiers in Water Quality Science". Co-authors on the talk were Jacob Riney (undergraduate, VT 2020), Caitlin Miller (undergraduate, VT 2019), and Erin Hotchkiss. Congratulations, Stephen!

You can view a copy of Stephen's slides here. The video of his presentation is embedded below for your viewing pleasure!