Megan Young specializes in isotope biogeochemistry research as a member of Carol Kendall’s Isotope Tracers Project at the USGS in Menlo Park, California. She also manages the Menlo Park Tritium Laboratory, providing tritium analysis for groundwater age dating within the USGS.
Megan received her Bachelor of Science in Geology from the University of Puget Sound, Washington, and her Ph.D. in Geological and Environmental Sciences from Stanford University in 2006, working with Dr. Adina Paytan. Her research has focused on using a wide range of natural tracers, including stable isotopes, geochemical constituents, and radioactive isotopes to trace natural and anthropogenic nutrient sources through surface and groundwater systems, and on the development and application of new isotope tracing techniques. Megan is currently working on large scale multi-isotope tracer studies in rivers, estuaries, and ground water in the San Francisco Bay Delta and Central Valley, California. One focus of her current research is on expanding the use of the oxygen isotopic composition of phosphate into freshwater systems as a tracer of phosphate sources and cycling, and she has co-authored several articles and book chapters on this topic.
Professional Experience
October 2010 to present: Research Hydrologist/Isotope Biogeochemist. Isotope Tracers Project, USGS Water Resources Mission Area, Menlo Park, CA
June 2006 to October 2010: Postdoctoral Researcher/Physical Scientist. Isotope Tracers Project, USGS Water Resources Discipline, Menlo Park, CA
September 2008 to January 2009: Postdoctoral Research Associate. Department of Land, Air and Water Resources, University of California, Davis, CA
Summer 2006: Instructor-Introduction to Oceanography (C82), U.C. Berkeley, Berkeley, CA
January 2006 to May 2006: Postdoctoral Researcher (short-term). Chemical Oceanography Lab, Stanford University, Stanford, CA
September 1999- January 2006: Graduate Student & Teaching Assistant (PhD program). Chemical Oceanography Lab, Stanford University, Stanford, CA
April 1998- July 1999: Geologist (for environmental consulting firm). Environmental Partners, Bellevue, WA
Fall 1997: Field Assistant, crab predation project in Bahia Kino, Sonora, Mexico
Education and Certifications
Ph.D., 2006. Stanford University, School of Earth Sciences, Department of Geological and Environmental Sciences (Stanford, CA)
B.S., 1997. University of Puget Sound, Geology Department (Tacoma, WA)
Honors and Awards
USGS Star Awards (annual), 2008-2012
NRP Lecture Series Speaker, 2010
Lieberman Fellowship, Stanford University, May 2003- June 2004
Stanford Graduate Fellowship: 3-year fellowship, Sept 1999- June 2003
McGee Foundation, Graduate Research Grants, 2000, 2001
Shell Fund Research Grants (conference travel), 2000, 2001, 2002, 2003
Phi Beta Kappa, Delta of Washington chapter, May 1997
Murdock Summer Science Research Grant for Senior Thesis, April 1996
Science and Products
Characterization of water residence time, nutrients, phytoplankton and related water quality constituents in the Cache Slough Complex of the California Sacramento-San Joaquin Delta in 2017 and 2018
Chemical and Stable Isotope Data for Discrete Water Samples Collected in the Northern Sacramento-San Joaquin Delta, 2011-2012
Over a third of groundwater in USA public-supply aquifers is Anthropocene-age and susceptible to surface contamination
Stable isotopes provide insight into sources and cycling of N compounds in the Sacramento-San Joaquin Delta, California, USA
Ocean connectivity drives trophic support for consumers in an intermittently closed coastal lagoon
Lateral carbon exports from drained peatlands: An understudied carbon pathway in the Sacramento-San Joaquin Delta, California
Tritium deposition in precipitation in the United States, 1953–2012
Use of flow cytometry and stable isotope analysis to determine phytoplankton uptake of wastewater derived ammonium in a nutrient-rich river
Methane fluxes from tropical coastal lagoons surrounded bymangroves, Yucatán, Mexico
Bayesian nitrate source apportionment to individual groundwater wells in the Central Valley by use of elemental and isotopic tracers
Methane and sulfate dynamics in sediments from mangrove-dominated tropical coastal lagoons, Yucatan, Mexico
Use of stable isotopes of nitrogen and water to identify sources of nitrogen in three urban creeks of Durham, North Carolina, 2011-12
Applications of stable isotopes for regional to national-scale water quality and environmental monitoring programs
Characterizing the oxygen isotopic composition of phosphate sources to aquatic ecosystems
Science and Products
- Data
Characterization of water residence time, nutrients, phytoplankton and related water quality constituents in the Cache Slough Complex of the California Sacramento-San Joaquin Delta in 2017 and 2018
Data was collected in the Cache Slough Complex located in the northern San Francisco Estuary to characterize water quality parameters at high spatial resolution. Data collection was conducted on three separate occasions: October 2017, May 2018, and October 2018. Data set includes nitrate, ammonium, ortho-phosphate, dissolved organic carbon, temperature, conductivity, dissolved oxygen, turbidity, cChemical and Stable Isotope Data for Discrete Water Samples Collected in the Northern Sacramento-San Joaquin Delta, 2011-2012
This data set consists of chemical and stable isotope data obtained through the analysis of discrete water samples collected from 14 fixed sampling locations in the northern Sacramento-San Joaquin Delta at roughly monthly intervals between April 2011 and November 2012. - Publications
Filter Total Items: 15
Over a third of groundwater in USA public-supply aquifers is Anthropocene-age and susceptible to surface contamination
The distribution of groundwater age is useful for evaluating the susceptibility and sustainability of groundwater resources. Here, we compute the aquifer-scale cumulative distribution function to characterize the age distribution for 21 Principal Aquifers that account for ~80% of public-supply pumping in the United States. The aquifer-scale cumulative distribution function for each Principal AquifAuthorsBryant Jurgens, Kirsten Faulkner, Peter B. McMahon, Andrew Hunt, Gerolamo C. Casile, Megan B. Young, Kenneth BelitzStable isotopes provide insight into sources and cycling of N compounds in the Sacramento-San Joaquin Delta, California, USA
River deltas and their diverse array of aquatic environments are increasingly impacted by anthropogenic inputs of nitrogen (N). These inputs can alter the N biogeochemistry of these systems and promote undesirable phenomena including harmful algae blooms and invasive aquatic macrophytes. To examine N sources and biogeochemical processes in the Sacramento-San Joaquin Delta, a river delta located inAuthorsJoseph K. Fackrell, Tamara E. C. Kraus, Megan B. Young, Carol Kendall, Sara PeekOcean connectivity drives trophic support for consumers in an intermittently closed coastal lagoon
Estuarine food webs are complex, as marine, freshwater, and terrestrial inputs combine and contribute variable amounts of organic material. Seasonal fluctuations in precipitation amplify the dynamism inherent to estuarine food webs, particularly in lagoonal estuaries, which can be seasonally closed and disconnected from the ocean in low-runoff periods (bar-built lagoons). Despite their abundance aAuthorsMatthew Young, Frederick Feyrer, Darren Fong, Rachel C. Johnson, Tamara E. C. Kraus, Veronica Larwood, Elizabeth Stumpner, Megan B. YoungLateral carbon exports from drained peatlands: An understudied carbon pathway in the Sacramento-San Joaquin Delta, California
Degradation of peatlands via drainage is increasing globally and destabilizing peat carbon (C) stores. The effects of drainage on the timing and magnitude of lateral C losses from degraded peatlands remains understudied. We measured spatial and temporal variability in lateral C exports from three drained peat islands in the Sacramento‐San Joaquin Delta in California across the 2017 and 2018 waterAuthorsChristina M. Richardson, Joseph K. Fackrell, Tamara E. C. Kraus, Megan B. Young, Adina PaytanTritium deposition in precipitation in the United States, 1953–2012
Tritium is a radioactive isotope of hydrogen (half-life is equal to 12.32 years). Since it is part of the water molecule, tritium can be used to track and date groundwater and surface water when the history of tritium in precipitation and recharge is known. To facilitate that effort, tritium concentrations in precipitation were reconstructed from measurements and correlations for 10 precipitationAuthorsRobert L. Michel, Bryant C. Jurgens, Megan B. YoungUse of flow cytometry and stable isotope analysis to determine phytoplankton uptake of wastewater derived ammonium in a nutrient-rich river
Anthropogenic alteration of the form and concentration of nitrogen (N) in aquatic ecosystems is widespread. Understanding availability and uptake of different N sources at the base of aquatic food webs is critical to establishment of effective nutrient management programs. Stable isotopes of N (14N, 15N) are often used to trace the sources of N fueling aquatic primary production, but effective useAuthorsCalla M. Schmidt, Tamara E. C. Kraus, Megan B. Young, Carol KendallMethane fluxes from tropical coastal lagoons surrounded bymangroves, Yucatán, Mexico
Methane concentrations in the water column and emissions to the atmosphere were determined for three tropical coastal lagoons surrounded by mangrove forests on the Yucatán Peninsula, Mexico. Surface water dissolved methane was sampled at different seasons over a period of 2 years in areas representing a wide range of salinities and anthropogenic impacts. The highest surface water methane concentraAuthorsPei-Chuan Chuang, Megan B. Young, Andrew W. Dale, Laurence G. Miller, Jorge A Herrera-Silveira, Adina PaytanBayesian nitrate source apportionment to individual groundwater wells in the Central Valley by use of elemental and isotopic tracers
Groundwater quality is a concern in alluvial aquifers that underlie agricultural areas, such as in the San Joaquin Valley of California. Shallow domestic wells (less than 150 m deep) in agricultural areas are often contaminated by nitrate. Agricultural and rural nitrate sources include dairy manure, synthetic fertilizers, and septic waste. Knowledge of the relative proportion that each of these soAuthorsKatherine M Ransom, Mark N. Grote, Amanda Deinhart, Gary Eppich, Carol Kendall, Matthew E. Sanborn, A. Kate Sounders, Joshua Wimpenny, Qing-zhu Yin, Megan B. Young, Thomas HarterMethane and sulfate dynamics in sediments from mangrove-dominated tropical coastal lagoons, Yucatan, Mexico
Porewater profiles in sediment cores from mangrove-dominated coastal lagoons (Celestún and Chelem) on the Yucatán Peninsula, Mexico, reveal the widespread coexistence of dissolved methane and sulfate. This observation is interesting since dissolved methane in porewaters is typically oxidized anaerobically by sulfate. To explain the observations we used a numerical transport-reaction model that wasAuthorsP. C. Chuang, Megan B. Young, Andrew W. Dale, Laurence G. Miller, Jorge A. Herrera-Silveira, Adina PaytanUse of stable isotopes of nitrogen and water to identify sources of nitrogen in three urban creeks of Durham, North Carolina, 2011-12
A preliminary assessment of nitrate sources was conducted in three creeks that feed nutrient impaired Falls and Jordan Lakes in the vicinity of Durham County, North Carolina, from July 2011 to June 2012. Cabin Branch, Ellerbe Creek, and Third Fork Creek were sampled monthly to determine if sources of nitrate in surface water could be identified on the basis of their stable isotopic compositions. LAuthorsKristen Bukowski McSwain, Megan B. Young, Mary L. GiorginoApplications of stable isotopes for regional to national-scale water quality and environmental monitoring programs
Isotopes are a potentially powerful component of monitoring and assessment programs aimed at quantifying and mitigating alterations to environments from human activities. In particular, isotopic techniques have proved useful for tracing sources and sinks of various pollutants in large river basins, wetlands, and airsheds. Many of these studies have been conducted at the regional to national scaleAuthorsCarol Kendall, Megan B. Young, Steven R. SilvaCharacterizing the oxygen isotopic composition of phosphate sources to aquatic ecosystems
The oxygen isotopic composition of dissolved inorganic phosphate (δ18Op) in many aquatic ecosystems is not in isotopic equilibrium with ambient water and, therefore, may reflect the source δ18Op. Identification of phosphate sources to water bodies is critical for designing best management practices for phosphate load reduction to control eutrophication. In order for δ18O p to be a useful tool forAuthorsM.B. Young, K. McLaughlin, C. Kendall, W. Stringfellow, M. Rollog, K. Elsbury, E. Donald, A. Paytan