Current Projects
Thermal Susceptibility of Antarctic Soils to Heatwaves
We are leveraging long-term and high-frequency data to analyze and simulate the response of Antarctic soils to brief, but intense periods of abnormal warming. Our work will help guide future sampling and study design efforts related to the unique ecology and biogeochemistry of soils in the McMurdo Dry Valleys.
Consequences of Coastal Dam Removal for Water Quality and Forests
Sea-level rise threatens infrastructure that itself was designed to influence the way water bodies are connected. In collaboration with the Bristol County Water Authority, Save the Bay, and the Narragansett Bay Estuary Program, we are investigating how the rapid transition from a relatively still, freshwater to brackish free-flowing system, including tidal reconnection, following managed infrastructure retreat alters nutrient cycling and algal blooms. We are also studying the impacts of water table declines and tidal reconnection on riparian forests composed of species with differing water stress regulation strategies.
Lithologic Controls on Forest Resilience
My postdoctoral research focused on investigating how subsurface variability controls tree water use and resilience to drought. This work is part of the Bedrock Critical Zone Collaborative Network, an interdisciplinary project focused on understanding linkages between subsurface weathering, surface processes, and ecosystems across a network of sites in the United States.
Stream Corridor-Driven C-Q Relationships
Long-term C-Q relationships provide information about integrated hydro-biogeochemical processes occurring throughout catchments. Due to the challenges of parsing the influence of catchment and stream corridor biogeochemical processes on C-Q relationships, the latter are often ignored or assumed to be negligible. We have analyzed 25 years of data for 10 MDV streams to assess how stream corridor processes alone control C-Q relationship form and variability among a suite of solutes spanning biologically inert weathering products to primary nutrients.
Satellite-Based Analysis of Periphyton in Ephemeral Streams
Many periphyton communities exist in ephemeral and intermittent stream corridors where they can survive in desiccated states between periods of flow. Such mats are important drivers of water quality through nutrient cycling, but they are subject to scouring and burial as streamflow changes. This project examines how we can leverage the unique spectral reflectance signatures of different periphyton communities to map and analyze how algal mats respond to changing flow conditions at various temporal and spatial scales.
Recovering Lost Streamflow Data
Proglacial streams in the McMurdo Dry Valleys flow for only a few weeks per year with periods of intermittency punctuated by large diel flood events. Due to the cold and remote nature of these sites, gages often experience issues resulting in data gaps. The entire 2020-2021 flow season was not captured due to the COVID-19 pandemic. I am currently building and evaluating models to estimate daily streamflow discharge based on high-frequency meteorological, glacier surface, and active-layer datasets that often remain available even when gages fail.
Publications
In Review
Dorley, J., Singley, J.G., Covino, T.P., Singha, K., Gooseff, M.N., Van Horn, D., & González-Pinzón, R. Differences in stream respiration in an undisturbed vs. agricultural stream. Biogeosciences.
Published
(13) Kohler, T.J., Singley, J.G., Wlostowski, A.N., & McKnight, D.M. (2023). Nitrogen fixation facilitates stream microbial mat biomass across the McMurdo Dry Valleys, Antarctica. Biogeochemistry. DOI: 10.1007/s10533-023-01069-0
(12) Dorley, J., Singley, J.G., Covino, T.P., Singha, K., Gooseff, M.N., Van Horn, D., & González-Pinzón, R. (2023). Physical and stoichiometric controls on stream respiration in a headwater stream. Biogeosciences, 20, 3353-3366. DOI: 10.5194/bg-20-3353-2023
(11) Singley, J.G., Briggs, M., Hoagland, B., Lauer, R., Meeks, J., Regberg, A.B., Rey, D. M., Swift Bird, K., & Ward, A.S. (2023). Integrated field, model, and theoretical advances inform a predictive understanding of transport and transformation in the critical zone. Journal of Hydrology. DOI: 10.1016/j.jhydrol.2023.129653
(10) Singley, J.G., Gooseff, M.N., Salvatore, M.R., McKnight, D.M., & Hinckley, E.S. (2023). Differentiating physical and biological storage of nitrogen along an intermittent Antarctic stream corridor. Freshwater Science, 42(3). DOI: 10.1086/725676
(9) Singley, J.G., Singha, K., Gooseff, M.N., Ward, A.S., González-Pinzón, R., Covino, T.P., Dorley, J., & Hinckley, E.S. (2022). Identification of hyporheic extent and functional zonation during seasonal streamflow recession by unsupervised clustering of time-lapse electrical resistivity models. Hydrological Processes, 36(10), e14713. DOI: 10.1002/hyp.14713
(8) Zdasiuk, B.J., Chen, C.Y., McCormick, S.D., Nislow, K.H., Singley, J.G., & Kelly, J.T. (2022). Evaluating acid-aluminum stress in streams of the Northeastern U.S. at watershed, fish community and physiological scales. Ecological Indicators, 144. DOI: 10.1016/j.ecolind.2022.109480
(7) Hensley, R.T., Singley, J.G., & Gooseff, M.N. (2022). Pulses within Pulses: Concentration-discharge relationships across temporal scales in a snowmelt-dominated Rocky Mountain catchment. Hydrological Processes, 36(9), e14700. DOI: 10.1002/hyp.14700
(6) González-Pinzón, R., J. Dorley, J.G. Singley, K. Singha, M.N. Gooseff, and T.P. Covino (2022). TIPT: The Tracer Injection Planning Tool. Environmental Modeling and Software, 156. DOI: 10.1016/j.envsoft.2022.105504
(5) Fortner, S.K., Manduca, C., Ali, H.N., Saup, C.M., Nyarko, S.C., Othus-Gault, S., Perera, V., Tong, V.C.H., Gold, A., Furman, T., Arthurs, L., Mulvey, B., St. John, K., Singley, J.G., Johnson, E.T., Witter, M., Batchelor, R., Carter, D., Damas, M.C., Lemay, L., Layou, K., Low, R., Wang, H., Olson-Sawyer, K., Pallant, A., Ryker, K., Lukes, L., LaDue, N., & van der Hoeven Kraft, K. (2022). Geoscience Education Perspectives on Integrated, Coordinated, Open, Networked (ICON) Science. Earth and Space Science, 9, e2022EA002298. DOI: 10.1029/2022EA002298
*member of the diversity, equity, inclusion, and justice writing team
(4) Singley, J.G., Gooseff, M.N., McKnight, D.M., & Hinckley, E.S. (2021). The role of hyporheic connectivity in determining nitrogen availability: Insights from an intermittent Antarctic stream, Journal of Geophysical Research: Biogeosciences, 126, e2021JG006309. DOI: 10.1029/2021JG006309
(3) Heindel, R.C., Darling, J.P., Singley, J.G., Bergstrom, A.J., McKnight, D.M., Welch, K.A., Lukkari, B., & Gooseff, M.N. (2021). Diatoms trace organic matter retention and processing in hyporheic sediments in the McMurdo Dry Valleys, Antarctica. Journal of Geophysical Research: Biogeosciences, 126, e2020JG006097. DOI: 10.1029/2020JG006097
(2) Bergstrom, A.J., Gooseff, M.N., Singley, J.G., Cohen, M.J., & Welch, K.A. (2020). Nutrient uptake in the supraglacial stream network of an Antarctic glacier. Journal of Geophysical Research: Biogeosciences, 125, e2020JG005679. DOI: 10.1029/2020JG005679
(1) Singley, J.G., Wlostowski, A.N., Bergstrom, A.J., Sokol, E.R., Torrens, C.L., Jaros, C., Wilson, C.E., Hendrickson, P.J., & Gooseff, M.N. (2017). Characterizing hyporheic exchange processes using high‐frequency electrical conductivity‐discharge relationships on sub-hourly to interannual timescales. Water Resources Research, 53(5), 4124-4141. DOI: 10.1002/2016WR019739
FAIR Data Products
Singley, J.G., M.N. Gooseff, and E.S. Hinckley (2021). Ammonium desorption of hyporheic sediments from Von Guerard Stream, McMurdo Dry Valleys, Antarctica (January 2019). Environmental Data Initiative. DOI: 10.6073/pasta/89e07484a91d8b503ae19d772555fbb4
Singley, J.G., M.N. Gooseff, D.M. McKnight, and E.S. Hinckley (2021). Surface and hyporheic porewater chemistry and sediment nitrification potentials in Von Guerard Stream, McMurdo Dry Valleys, Antarctica (2018-2020). Environmental Data Initiative. DOI: 10.6073/pasta/d6e4301bf93fba0fef6fd5c33a092aaf
Heindel, R.C., J.G. Singley, A.J. Bergstrom, J.P. Darling, K.A. Welch, D.M. McKnight, and M.N. Gooseff. 2020. McMurdo Dry Valleys LTER: Hyporheic sediment characteristics from transects across Von Guerard Stream, Taylor Valley, Antarctica, January 2019. Environmental Data Initiative. DOI: 10.6073/pasta/9e8dfbcaa6bba367d162eb6dede2937b
Darling, J.P, R.C. Heindel, J.G. Singley, A.J. Bergstrom, and D.M. McKnight. 2020. McMurdo Dry Valleys LTER: Hyporheic diatom community assemblages from transects across Von Guerard Stream, Taylor Valley, Antarctica, January 2019. Environmental Data Initiative. DOI: 10.6073/pasta/f79bdbca0e3e97ef5f1b4007d2f008eb