Rob Striegl is an Emeritus Research Hydrologist with the USGS Water Resources Mission Area.
Professional Studies/Experience
I am a Research Aquatic Biogeochemist / Hydrologist located in Boulder, Colorado. My research focuses on the role of inland waters in the global carbon cycle and on hydrologic, climatic, and disturbance controls on the biogeochemical cycling, sequestration, transport, and surface-atmosphere exchange of aquatic carbon. Investigations conducted by me and my research group address a broad range of field, laboratory and modeling studies, including the transport of inorganic and organic carbon by surface and subsurface waters; the production, consumption, and atmospheric exchange of carbon dioxide and methane by streams, rivers, lakes, reservoirs, and soils; the effects of climate warming, permafrost thaw, and other disturbances on the carbon cycle of subarctic and boreal regions; and extrapolation of inland waters carbon biogeochemical processes and rates of carbon exchange from site to regional, continental, and global scales. I lead USGS LandCarbon investigations of Ecosystem Carbon Sequestration and Greenhouse Gas Exchange by Inland Waters of the USA and am also the Principal Investigator of the NASA Arctic-Boreal Vulnerability Experiment (ABoVE) project "Aquatic Vulnerabilites of Inland Waters and the Aquatic Carbon Cycle to Changing Permafrost and Climate across Boreal North America".
Professional societies/affiliations/committees/editorial boards
- Carbon Cycle Scientific Steering Group,
- U.S. Carbon Cycle Science Program,
- U.S. Global Change Research Program
- Associate Editor, Journal of Geophysical Research - Biogeosciences, American Geophysical Union
Education and Certifications
Education
PhD: University of Wisconsin - Madison; Oceanography and Limnology
MSc: Univeristy of Illinois - Urbana; Biology / Aquatic Ecology
BSc: Western Illinois Univeristy - Macomb; Zoology
Science and Products
Assessment of Critical Landscape Conditions and Potential Change in the Coastal Plain of the Arctic National Wildlife Refuge to Support Habitat Management Decision Making
Shingobee Headwaters Aquatic Ecosystems Project (SHAEP)
Arctic Boreal Vulnerability Experiment (ABoVE)
Nome Creek Experimental Watershed
Transport of dissolved organic matter by river networks from mountains to the sea: a re-examination of the role of flow across temporal and spatial scales
Total mercury, bulk density, percent organic matter, and percent organic carbon measured in permafrost cores from the interior and northern slope of Alaska and previously published studies
Water quality and gas fluxes of Interior Alaska (2014-2018)
Water Level, Temperature, and Discharge of Headwater Streams in the Yukon River Basin, Alaska, 2016 and 2017
Water quality, quantity, and gas fluxes of the Upper Mississippi River basin (WY 2012-2016)
Dissolved organic carbon and nitrogen release from boreal Holocene permafrost and seasonally frozen soils of Alaska
Arctic-boreal lakes of interior Alaska dominated by contemporary carbon
Long-term trends in Arctic riverine chemistry signal multi-faceted northern change
Quantification of wetland vegetation communities features with airborne AVIRIS-NG, UAVSAR, and UAV LiDAR data in Peace-Athabasca Delta
High voltage: The molecular properties of redox-active dissolved organic matter in northern high-latitude lakes
Integrating terrestrial and aquatic ecosystems to constrain estimates of land-atmosphere carbon exchange
Dissolved carbon export by large river systems is influenced by source area heterogeneity
Anthropogenic landcover impacts fluvial dissolved organic matter composition in the Upper Mississippi River Basin
Hydrologic and landscape controls on dissolved organic matter composition across western North American Arctic lakes
Bioavailability of dissolved organic matter varies with anthropogenic landcover in the Upper Mississippi River Basin
The importance of lake emergent aquatic vegetation for estimating Arctic-boreal methane emissions
Heterogeneous patterns of aged organic carbon export driven by hydrologic flow paths, soil texture, fire, and thaw in discontinuous permafrost headwaters
Complex vulnerabilities of the water and aquatic carbon cycles to permafrost thaw
Science and Products
- Science
Assessment of Critical Landscape Conditions and Potential Change in the Coastal Plain of the Arctic National Wildlife Refuge to Support Habitat Management Decision Making
Areas along the Arctic coast are changing the fastest among all of Earth’s habitats due to climate change. The Arctic coast is a fragile ecosystem that provides habitat for migratory birds, endangered species, and species critical for local subsistence living. In this area, permafrost is thawing rapidly, changing how much and when water reaches rivers, ponds, lakes, wetlands and groundwater. In ad...Shingobee Headwaters Aquatic Ecosystems Project (SHAEP)
For 43 years, the Shingobee Headwaters Aquatic Ecosystems Project (SHAEP) brought together scientists from the USGS along with students and professors from universities in Minnesota, North Dakota, Wisconsin, and California to study the physical, chemical, and biological processes of lakes, wetlands, and streams at local and watershed scales. In early 2022, The University of Minnesota and Bemidji...Arctic Boreal Vulnerability Experiment (ABoVE)
ABoVE: Vulnerability of inland waters and the aquatic carbon cycle to changing permafrost and climate across boreal northwestern North America. Carbon released from thawing permafrost may fuel terrestrial and aquatic ecosystems or contribute to greenhouse gas emission, leading to a potential warming feedback and further thaw.Nome Creek Experimental Watershed
The Nome Creek Experimental Watershed (NCEW) has been the site of multiple studies focused on understanding hydrology, biogeochemistry, and ecosystem changes related to permafrost thaw and fire in the boreal forest.Transport of dissolved organic matter by river networks from mountains to the sea: a re-examination of the role of flow across temporal and spatial scales
The transport of dissolved organic matter (DOM) by rivers is an important component of the global carbon cycle, affects ecosystems and water quality, and reflects biogeochemical and hydrological processes in watersheds. Understanding the fundamental relationships between discharge and DOM concentration and composition reveals important information about watershed flow paths, soil flushing, connect - Data
Total mercury, bulk density, percent organic matter, and percent organic carbon measured in permafrost cores from the interior and northern slope of Alaska and previously published studies
This data release contains two datasets (see child items below). The first dataset, "MasterDB-csv-published-final.csv", includes 11,000 published measurements of sediment total mercury (STHg, nanograms per gram of soil, dry), bulk density (BD, grams per cm3 of soil, dry), percent of soil organic matter (%OM, loss on ignition, LOI), percent of soil organic carbon (%SOC, calculated using the RedfiWater quality and gas fluxes of Interior Alaska (2014-2018)
This product consists of multiple tabular datasets and associated metadata of water quality information related to rivers, streams, and lakes in the Yukon River watershed between 2014 and 2018. This data release is apart of the National Aeronautics and Space Administration (NASA) funded Arctic-Boreal Vulnerability Experiment (ABoVE) and is an assessment of water quality and greenhouse gas fluxes wWater Level, Temperature, and Discharge of Headwater Streams in the Yukon River Basin, Alaska, 2016 and 2017
This data set includes 15-minute interval data on stream temperature, stage, and discharge from low-order streams in the Yukon River Basin in interior Alaska, collected during the summer months. The depth of the water and temperature were determined using a combined pressure transducer and temperature sensor that was deployed through the summer months. Different sensors were used in each stream anWater quality, quantity, and gas fluxes of the Upper Mississippi River basin (WY 2012-2016)
This product consists of one tabular dataset and associated metadata of water quality information related to rivers, streams, and reservoirs in the Upper Mississippi River watershed between 2012 and 2016. This data release is a part of a national assessment of freshwater aquatic carbon fluxes. Data consist of organic and inorganic carbon related species, carbon dioxide and methane gas fluxes calcuDissolved organic carbon and nitrogen release from boreal Holocene permafrost and seasonally frozen soils of Alaska
Permafrost (perennially frozen) and active-layer (seasonally thawed) soils varying in soil carbon (C) and nitrogen (N) content and radiocarbon age were collected from three sites in interior Alaska to determine potential release of dissolved organic carbon (DOC), total dissolved N (TDN), dissolved organic nitrogen (DON), and dissolved inorganic nitrogen (DIN) upon thaw. Soil cores were cut into 15 - Multimedia
- Publications
Filter Total Items: 141
Arctic-boreal lakes of interior Alaska dominated by contemporary carbon
Northern high-latitude lakes are critical sites for carbon processing and serve as potential conduits for the emission of permafrost-derived carbon and greenhouse gases. However, the fate and emission pathways of permafrost carbon in these systems remain uncertain. Here, we used the natural abundance of radiocarbon to identify and trace the predominant sources of methane, carbon dioxide, dissolvedAuthorsFenix Garcia-Tigreros, Clayton D. Elder, Martin R. Kurek, Benjamin L. Miller, Xiaomei Xu, Kimberly Wickland, Cluadia I. Czimczik, Mark M. Dornblaser, Robert G. Striegl, Ethan D. Kyzivat, Laurence C. Smith, Robert G.M. Spencer, Charles E. Miller, David ButmanLong-term trends in Arctic riverine chemistry signal multi-faceted northern change
Rivers integrate processes occurring throughout their watersheds and are therefore sentinels of change across broad spatial scales. River chemistry also regulates ecosystem function across Earth’s land–ocean continuum, exerting control from the micro- (for example, local food web) to the macro- (for example, global carbon cycle) scale. In the rapidly warming Arctic, a wide range of processes—fromAuthorsSuzanne E. Tank, James W. McClelland, Robert G. M. Spencer, Alexander I. Shiklomanov, Anya Suslova, Florentina Moatar, Rainer Amon, Lee W. Cooper, Greg Elias, Vyacheslav Gordeev, Christopher Guay, Tatiana Gurtovaya, Lyudmila Kosmenko, Edda A. Mutter, Bruce Peterson, Bernhard Peucker-Ehrenbrink, Peter Raymond, Paul Schuster, Lindsay Scott, Robin Staples, Robert G. Striegl, Mikhail Tretiakov, Alexander V. Zhulidov, Nikita Zimov, Sergey Zimov, Robert M. HolmesQuantification of wetland vegetation communities features with airborne AVIRIS-NG, UAVSAR, and UAV LiDAR data in Peace-Athabasca Delta
Arctic-boreal wetlands, important ecosystems for biodiversity and ecological services, are experiencing hydrological changes including permafrost thaw, earlier snowmelt, and increased wildfire susceptibility. These changes are affecting wetland productivity, species diversity, and biogeochemical cycles. However, given the diverse forms and structures of wetland vegetation communities, traditionalAuthorsChao Wang, Tamlin M. Pavelsky, Ethan D. Kyzivat, Fenix Garcia-Tigreros, Erika Podest, Fangfang Yao, Xiao Yang, Shuai Zhang, Conghe Song, Theodore Langhorst, Wayana Dolan, Martin R. Kurek, Merritt E. Harlan, Laurence C. Smith, David Butman, Robert G.M. Spencer, Colin J. Gleason, Kimberly Wickland, Robert G. Striegl, Daniel L. PetersHigh voltage: The molecular properties of redox-active dissolved organic matter in northern high-latitude lakes
Redox-active functional groups in dissolved organic matter (DOM) are crucial for microbial electron transfer and methane emissions. However, the extent of aquatic DOM redox properties across northern high-latitude lakes and their relationships with DOM composition have not been thoroughly described. We quantified electron donating capacity (EDC) and electron accepting capacity (EAC) in lake DOM frAuthorsMartin R. Kurek, Fenix Garcia-Tigreros, Natalie A. Nichols, Gregory K. Druschel, Kimberly Wickland, Mark M. Dornblaser, Robert G. Striegl, Sydney F. Niles, Amy M. McKenna, Pieter J.K Aukes, Ethan D. Kyzivat, Chao Wang, Laurence C. Smith, Sherry L. Schiff, David Butman, Robert G.M. SpencerIntegrating terrestrial and aquatic ecosystems to constrain estimates of land-atmosphere carbon exchange
In this Perspective, we put forward an integrative framework to improve estimates of land-atmosphere carbon exchange based on the accumulation of carbon in the landscape as constrained by its lateral export through rivers. The framework uses the watershed as the fundamental spatial unit and integrates all terrestrial and aquatic ecosystems as well as their hydrologic carbon exchanges. ApplicationAuthorsJoan Casas-Ruiz, Pascal Bodmer, Kelly Ann Bona, David Butman, Mathilde Couturier, Erik J.S. Emilson, Kerri Finlay, Helene Genet, Daniel B. Hayes, Jan Karlsson, David Paré, Changhui Peng, Robert G. Striegl, Jackie Webb, Xinyuan Wei, Sue Ziegler, Paul Del GiorgioDissolved carbon export by large river systems is influenced by source area heterogeneity
Rivers and streams export inorganic and organic carbon derived from contributing landscapes and so downstream carbon fluxes are important quantitative indicators of change in ecosystem function and for the full accounting of terrestrial carbon budgets. Carbon concentration-discharge (C-Q) relationships in rivers provide important information about carbon source and behavior in watersheds and are uAuthorsEdward G. Stets, Robert G. Striegl, Kimberly Wickland, Mark Dornblaser, Sydney FoksAnthropogenic landcover impacts fluvial dissolved organic matter composition in the Upper Mississippi River Basin
Landcover changes have altered the natural carbon cycle; however, most landcover studies focus on either forest conversion to agriculture or urban, rarely both. We present differences in dissolved organic carbon (DOC) concentrations and dissolved organic matter (DOM) molecular composition within Upper Mississippi River Basin low order streams and rivers draining one of three dominant landcovers (fAuthorsDerrick R. Vaughn, Anne M. Kellerman, Kimberly Wickland, Robert G. Striegl, David C. Podgorski, Jon R. Hawkings, Jaap Nienhuis, Mark Dornblaser, Edward G. Stets, Robert G. M. SpencerHydrologic and landscape controls on dissolved organic matter composition across western North American Arctic lakes
Northern high-latitude lakes are hotspots for cycling dissolved organic carbon (DOC) inputs from allochthonous sources to the atmosphere. However, the spatial distribution of lake dissolved organic matter (DOM) is largely unknown across Arctic-boreal regions with respect to the surrounding landscape. We expand on regional studies of northern high-latitude DOM composition by integrating DOC concentAuthorsMartin R. Kurek, Fenix Garcia-Tigreros, Kimberly Wickland, Karen E. Frey, Mark Dornblaser, Robert G. Striegl, Sydney F. Niles, Amy M. McKenna, Pieter J.K Aukes, Ethan D. Kyzivat, Chao Wang, Tamlin M. Pavelsky, Laurence C. Smith, Sherry L. Schiff, David Butman, Robert G.M. SpencerBioavailability of dissolved organic matter varies with anthropogenic landcover in the Upper Mississippi River Basin
Anthropogenic conversion of forests and wetlands to agricultural and urban landcovers impacts dissolved organic matter (DOM) within streams draining these catchments. Research on how landcover conversion impacts DOM molecular level composition and bioavailability, however, is lacking. In the Upper Mississippi River Basin (UMRB), water from low-order streams and rivers draining one of three dominanAuthorsDerrick R. Vaughn, Anne M. Kellerman, Kimberly Wickland, Robert G. Striegl, David C. Podgorski, Jon R. Hawkings, Jaap H. Nienhuis, Mark M. Dornblaser, Edward G. Stets, Robert G.M. SpencerThe importance of lake emergent aquatic vegetation for estimating Arctic-boreal methane emissions
Areas of lakes that support emergent aquatic vegetation emit disproportionately more methane than open water but are under-represented in upscaled estimates of lake greenhouse gas emissions. These shallow areas are typically less than ∼1.5 m deep and can be detected with synthetic aperture radar (SAR). To assess the importance of lake emergent vegetation (LEV) zones to landscape-scale methane emisAuthorsEthan D. Kyzivat, Laurence C. Smith, Fenix Garcia-Tigreros, Chang Huang, Chao Wang, Theodore Langhorst, Jessica V. Fayne, Merritt E. Harlan, Yuta Ishitsuka, Dongmei Feng, Wayana Dolan, Lincoln H. Pitcher, Kimberly Wickland, Mark Dornblaser, Robert G. Striegl, Tamlin M. Pavelsky, David E. Butman, Colin J. GleasonHeterogeneous patterns of aged organic carbon export driven by hydrologic flow paths, soil texture, fire, and thaw in discontinuous permafrost headwaters
Climate change is thawing and potentially mobilizing vast quantities of organic carbon (OC) previously stored for millennia in permafrost soils of northern circumpolar landscapes. Climate-driven increases in fire and thermokarst may play a key role in OC mobilization by thawing permafrost and promoting transport of OC. Yet, the extent of OC mobilization and mechanisms controlling terrestrial-aquatAuthorsJoshua C. Koch, Matthew Bogard, David Butman, Kerri Finlay, Brian A. Ebel, Jason James, Sarah Ellen Johnston, Torre Jorgenson, Neal Pastick, Rob Spencer, Rob Striegl, Michelle A. Walvoord, Kimberly WicklandComplex vulnerabilities of the water and aquatic carbon cycles to permafrost thaw
The spatial distribution and depth of permafrost are changing in response to warming and landscape disturbance across northern Arctic and boreal regions. This alters the infiltration, flow, surface and subsurface distribution, and hydrologic connectivity of inland waters. Such changes in the water cycle consequently alter the source, transport, and biogeochemical cycling of aquatic carbon (C), itsAuthorsMichelle A. Walvoord, Robert G. Striegl