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Staff information


Jim Moran

Environ Transform & Interact
Joint Appointment
Pacific Northwest National Laboratory
PO Box 999
Richland, WA 99352


Since arriving at PNNL Dr. Moran has been studying microbial interactions in phototrophic and non-phototrophic microbial mats in hypersaline, hyperthermophilic, and acid systems and more recently the microbial and geochemical control of nutrient cycling in rhizosphere systems. These studies have utilized a series of light stable isotope (primarily C, H, and N) methods both with and without labeled substrate tracers. In addition to these efforts, Dr. Moran has also used a suite of stable isotope approaches to support a number of chemical and biological fingerprinting efforts, basic animal ecology research, and in instrument development activities. Specific instrument development efforts have led to design and construction of the laser ablation isotope ratio mass spectrometry system capable of making spatially prescribed stable isotope measurements over solid surfaces. Dr. Moran is also leading current efforts to develop extremely high sensitivity isotope measurements using capillary absorption spectroscopy having order of magnitude decreases in sample size requirements over traditional mass spectrometry approaches.

Dr. Moran also serves as the lead for the Isotope and Chemical Analysis team within the Environmental Transformations and Interactions group.

Research Interests

  • Microbial interactions
  • Rhizosphere processes
  • Microbial ecology
  • Stable isotope geochemistry
  • Biogeochemistry

Education and Credentials

  • Post-doctoral: McMaster University, Hamilton, Ontario, 2007-2008
  • Ph.D.: The Pennsylvania State University, State College, PA, Geosciences, 2007
  • B.A.: Lawrence University, Appleton, WI, Chemistry and Geology; Biology minor, 2000

Affiliations and Professional Service

  • American Chemical Society
  • American Geophysical Union
  • European Geosciences Union
  • Geochemical Society
  • Soil Science Society of America

PNNL Publications


  • Cleary D.M., T.J. Linley, J. Kriesel, A. Fahrland, J.F. Kelly, and J.J. Moran. 2023. "Laser Ablation-Capillary Absorption Spectroscopy: A novel approach for high throughput and increased spatial resolution measurements of d13C in plant-soil systems." Soil Biology and Biochemistry 187, no. 2023:Art. No. 109208. PNNL-SA-191463. doi:10.1016/j.soilbio.2023.109208
  • Kew W.R., R.M. Boiteau, J. Eiler, L. Pasa-Tolic, and J.J. Moran. 2023. "Natural Abundance Isotope Ratio Measurements of Organic Molecules using 21 T FTICR MS." Analytical Chemistry 95, no. 47:17203-17211. PNNL-SA-184505. doi:10.1021/acs.analchem.3c01816
  • Moran J.J., H.C. Bernstein, J.M. Mobberley, A.M. Thompson, Y. Kim, K.L. Dana, and A.B. Cory, et al. 2023. "Daylight-driven carbon exchange through a vertically structured microbial community." Frontiers in Microbiology 14. PNNL-SA-138227. doi:10.3389/fmicb.2023.1139213
  • Nims M.K., T.J. Linley, and J.J. Moran. 2023. "Temperature-dependent oxygen isotope fractionation in otoliths of juvenile Chinook salmon (Oncorhynchus tshawytscha)." Applied Geochemistry 155. PNNL-SA-175823. doi:10.1016/j.apgeochem.2023.105723
  • Zegeye E., V.S. Lin, J. Nunez, N.A. Sconzo, S.O. Purvine, A.T. Wright, and J.J. Moran. 2023. "Enzymatically hydrolyzed fluorescence-based chemical probe enables in situ mapping of chitinase activity in the rhizosphere." Soil Biology and Biochemistry 184. PNNL-SA-182442. doi:10.1016/j.soilbio.2023.109122


  • Moran J.J., and C.R. McGrath. 2021. "Comparison of methods for mapping rhizosphere processes in the context of their surrounding root and soil environments." BioTechniques 71, no. 6:604-614. PNNL-SA-160671. doi:10.2144/btn-2021-0021
  • Schweitzer H., N. Aalto, W. Busch, D. Chan, M. Chiesa, E. Elvevoll, and R. Gerlach, et al. 2021. "Innovating carbon-capture biotechnologies through ecosystem-inspired solutions." One Earth 4, no. 1:49-59. PNNL-SA-154220. doi:10.1016/j.oneear.2020.12.006
  • White R.A., J.J. Rosnow, P.D. Piehowski, C.J. Brislawn, and J.J. Moran. 2021. "In situ non-destructive temporal measurements of the rhizosphere microbiome ‘hot-spots,’ using metaproteomics." Agronomy 11, no. 11:Art. No. 2248. PNNL-SA-166644. doi:10.3390/agronomy11112248


  • Anderton C.R., J.M. Mobberley, J.K. Cole, J. Nunez, R.F. Starke, A.A. Boaro, and Y. Yesiltepe, et al. 2020. "Nitrogen source governs community carbon metabolism in a model hypersaline benthic phototrophic biofilm." mSystems 5, no. 3:Article No. e00260-20. PNNL-SA-145330. doi:10.1128/mSystems.00260-20
  • Boiteau R.M., R.K. Kukkadapu, J.B. Cliff, C.R. Smallwood, L. Kovarik, M.G. Wirth, and M.H. Engelhard, et al. 2020. "Calcareous organic matter coatings sequester siderophores in alkaline soils." Science of the Total Environment 724. PNNL-SA-147851. doi:10.1016/j.scitotenv.2020.138250
  • Callister S.J., J.J. Moran, L. McCue, and L. Pasa-Tolic. 2020. Microbial Ecology of the Plant Rhizosphere (PlantMicrobe). PNNL-30791. Richland, WA: Pacific Northwest National Laboratory. Microbial Ecology of the Plant Rhizosphere (PlantMicrobe)
  • Larimer C.J., E.H. Denis, J.D. Suter, and J.J. Moran. 2020. "Optical coherence tomography imaging of plant root growth in soil." Applied Optics 59, no. 8:2474-2481. PNNL-SA-149582. doi:10.1364/AO.384674
  • Lin V.S., J.J. Rosnow, M.Y. McGrady, D.N. Smercina, J. Nunez, R.S. Renslow, and J.J. Moran. 2020. "Non-destructive spatial analysis of phosphatase activity and total protein distribution in the rhizosphere using a root blotting method." Soil Biology and Biochemistry 146. PNNL-SA-149591. doi:10.1016/j.soilbio.2020.107820
  • Steinke L.A., G.W. Slysz, M.S. Lipton, C. Klatt, J.J. Moran, M.F. Romine, and J. Wood, et al. 2020. "Short-term stable isotope probing of proteins reveals taxa incorporating inorganic carbon in a hot spring microbial mat." Applied and Environmental Microbiology 86, no. 7:Article No. e01829-19. PNNL-SA-148749. doi:10.1128/AEM.01829-19
  • Velickovic D., V.S. Lin, A. Rivas-Ubach, C.R. Anderton, and J.J. Moran. 2020. "An approach for broad molecular imaging of the root-soil interface via indirect matrix-assisted laser desorption/ionization mass spectrometry." Soil Biology and Biochemistry 146. PNNL-SA-150080. doi:10.1016/j.soilbio.2020.107804


  • Brislawn C.J., E.B. Graham, K.L. Dana, P.D. Ilhardt, S.J. Fansler, W.B. Chrisler, and J.B. Cliff, et al. 2019. "Forfeiting the priority effect: turnover defines biofilm community succession." The ISME Journal 13, no. 7:1865-1877. PNNL-SA-133067. doi:10.1038/s41396-019-0396-x
  • Denis E.H., P.D. Ilhardt, A.E. Tucker, N.L. Huggett, J.J. Rosnow, and J.J. Moran. 2019. "Spatially tracking carbon through the root-rhizosphere-soil system using laser ablation-IRMS." Journal of Plant Nutrition and Soil Science 182, no. 3:401-410. PNNL-SA-135618. doi:10.1002/jpln.201800301
  • Ilhardt P.D., J. Nunez, E.H. Denis, J.J. Rosnow, E.J. Krogstad, R.S. Renslow, and J.J. Moran. 2019. "High-resolution elemental mapping of the root-rhizosphere-soil continuum using laser-induced breakdown spectroscopy (LIBS)." Soil Biology and Biochemistry 131. PNNL-SA-137289. doi:10.1016/j.soilbio.2018.12.029
  • Waldo N.B., B. Hunt, E. Fadely, J.J. Moran, and R.B. Neumann. 2019. "Plant Root Exudates Increase Methane Emissions through Direct and Indirect Pathways." Biogeochemistry 145, no. 1-2:213-234. PNNL-SA-147383. doi:10.1007/s10533-019-00600-6


  • Moran J.J., C.G. Fraga, and M.K. Nims. 2018. "Stable-Carbon Isotope Ratios for Sourcing the Nerve-Agent Precursor Methylphosphonic Dichloride and Its Products." Talanta 186. PNNL-SA-130651. doi:10.1016/j.talanta.2018.04.021


  • Bernstein H.C., C.J. Brislawn, K.L. Dana, T.M. Flores-Wentz, A.B. Cory, S.J. Fansler, and J.K. Fredrickson, et al. 2017. "Primary and heterotrophic productivity relate to multikingdom diversity in a hypersaline mat." FEMS Microbiology Ecology 93, no. 10:Article No. fix121. PNNL-SA-127139. doi:10.1093/femsec/fix121
  • Bernstein H.C., C.J. Brislawn, R.S. Renslow, K.L. Dana, B.R. Morton, S.R. Lindemann, and H. Song, et al. 2017. "Trade-offs between microbiome diversity and productivity in a stratified microbial mat." The ISME Journal 11, no. 2:405-414. PNNL-SA-120993. doi:10.1038/ismej.2016.133
  • Douglas P., D. Stolper, J. Eiler, A. Sessions, M. Lawson, Y. Shaui, and A. Bishop, et al. 2017. "Methane Clumped Isotopes: Progress and Potential for a New Isotopic Tracer." Organic Geochemistry 113. PNNL-SA-124415. doi:10.1016/j.orggeochem.2017.07.016
  • Jennings R., J.J. Moran, Z.J. Jay, J. Beam, L.M. Whitmore, M. Kozubal, and H.W. Kreuzer, et al. 2017. "Integration of metagenomic and stable carbon isotope evidence reveals the extent and mechanisms of carbon dioxide fixation in high-temperature microbial communities." Frontiers in Microbiology 8. PNNL-SA-119791. doi:10.3389/fmicb.2017.00088
  • Kriesel J.M., C.N. Makarem, M.C. Phillips, J.J. Moran, M. Coleman, L. Christensen, and J.F. Kelly. 2017. "Versatile, ultra-low sample volume gas analyzer using a rapid, broad-tuning ECQCL and a hollow fiber gas cell." In Next-Generation Spectroscopic Technologies X, April 9, 2017, Anaheim, California. Proceedings of the SPIE, edited by MA Druy, et al, 10210, Article No. 1021003. Bellingham, Washington:SPIE. PNNL-SA-125504. doi:10.1117/12.2262612
  • Mace E.K., C.E. Aalseth, T.R. Alexander, H.O. Back, A.R. Day, E.W. Hoppe, and M.E. Keillor, et al. 2017. "Simultaneous Measurement of Tritium and Radiocarbon by Ultra-Low-Background Proportional Counting." Applied Radiation and Isotopes 126. PNNL-SA-120393. doi:10.1016/j.apradiso.2016.12.033
  • Mobberley J.M., S.R. Lindemann, H.C. Bernstein, J.J. Moran, R.S. Renslow, J.T. Babauta, and D. Hu, et al. 2017. "Organismal and spatial partitioning of energy and macronutrient transformations within a hypersaline mat." FEMS Microbiology Ecology 93, no. 4:Article No. fix028. PNNL-SA-124562. doi:10.1093/femsec/fix028
  • Moran J.J., L. Whitmore, Z. Jay, R. Jennings, J. Beam, H.W. Kreuzer, and W.P. Inskeep. 2017. "Dual stable isotopes of CH4 from Yellowstone hot-springs suggest hydrothermal processes involving magmatic CO2." Journal of Volcanology and Geothermal Research 341. PNNL-SA-121866. doi:10.1016/j.jvolgeores.2017.05.011
  • Moran J.J., T.R. Alexander, C.E. Aalseth, H.O. Back, E.K. Mace, C.T. Overman, and A. Seifert, et al. 2017. "Improvements to sample processing and measurement to enable more widespread environmental application of tritium." Applied Radiation and Isotopes 126. PNNL-SA-120318. doi:10.1016/j.apradiso.2017.01.033
  • Szecsody J.E., M.J. Truex, B.D. Lee, C.E. Strickland, J.J. Moran, M. Snyder, and C.T. Resch, et al. 2017. Geochemical, Microbial, and Physical Characterization of 200-DV-1 Operable Unit Cores from Boreholes C9552, C9487, and C9488, Hanford Site Central Plateau. PNNL-26266. Richland, WA: Pacific Northwest National Laboratory.
  • Truex M.J., J.E. Szecsody, N. Qafoku, C.E. Strickland, J.J. Moran, B.D. Lee, and M. Snyder, et al. 2017. Contaminant Attenuation and Transport Characterization of 200-DV-1 Operable Unit Sediment Samples. PNNL-26208. Richland, WA: Pacific Northwest National Laboratory. Contaminant Attenuation and Transport Characterization of 200-DV-1 Operable Unit Sediment Samples">doi:10.2172/1368134.Contaminant Attenuation and Transport Characterization of 200-DV-1 Operable Unit Sediment Samples


  • Bonicalzi R., C.E. Aalseth, A.R. Day, E.W. Hoppe, E.K. Mace, J.J. Moran, and C.T. Overman, et al. 2016. "Optimization of Simultaneous Tritium-Radiocarbon Internal Gas Proportional Counting." Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment 813. PNNL-SA-111865. doi:10.1016/j.nima.2015.12.062
  • Mace E.K., C.E. Aalseth, A.R. Day, E.W. Hoppe, M.E. Keillor, J.J. Moran, and M.E. Panisko, et al. 2016. "First results of a simultaneous measurement of tritium and 14C in an ultra-low-background proportional counter for environmental sources of methane." Journal of Environmental Radioactivity 155-156. PNNL-SA-111748. doi:10.1016/j.jenvrad.2016.02.001
  • Mirjankar N.S., C.G. Fraga, A.J. Carman, and J.J. Moran. 2016. "Source Attribution of Cyanides using Anionic Impurity Profiling, Stable Isotope Ratios, Trace Elemental Analysis and Chemometrics." Analytical Chemistry 88, no. 3:1827-1834. PNNL-SA-113038. doi:10.1021/acs.analchem.5b04126
  • Moran J.J., L.M. Whitmore, N.G. Isern, M.F. Romine, K.M. Riha, W.P. Inskeep, and H.W. Kreuzer. 2016. "Formaldehyde as a carbon and electron shuttle between autotroph and heterotroph populations in acidic hydrothermal vents of Norris Geyser Basin, Yellowstone National Park." Extremophiles 20, no. 3:291-299. PNNL-SA-115653. doi:10.1007/s00792-016-0821-2
  • Moran J.J., M.L. Alexander, and A. Laskin. 2016. "Soil Carbon: Compositional and Isotopic Analysis." In Encyclopedia of Soil Science, 3rd Edition, edited by R Lal. Boca Raton, Florida:CRC Press. PNNL-SA-110016.
  • Yang H., H. Gandhi, A.J. Cornish, J.J. Moran, H.W. Kreuzer, N. Ostrom, and E.L. Hegg. 2016. "Isotopic fractionation associated with [NiFe]- and [FeFe]-hydrogenases." Rapid Communications in Mass Spectrometry 30, no. 2:285-292. PNNL-SA-107635. doi:10.1002/rcm.7432
  • Zachara J.M., J.J. Moran, C.T. Resch, S.R. Lindemann, A.R. Felmy, M.E. Bowden, and A.B. Cory, et al. 2016. "Geo- and Biogeochemical Processes in a Heliothermal Hypersaline Lake." Geochimica et Cosmochimica Acta 181. PNNL-SA-108309. doi:10.1016/j.gca.2016.02.001


  • Jennings R., L.M. Whitmore, J.J. Moran, H.W. Kreuzer, and W.P. Inskeep. 2014. "Carbon dioxide fixation by Metallosphaera yellowstonensis and acidothermophilic iron-oxidizing microbial communities from Yellowstone National Park." Applied and Environmental Microbiology 80, no. 9:2665-2671. PNNL-SA-98802. doi:10.1128/AEM.03416-13
  • Kreuzer H.W., E.A. Hill, J.J. Moran, R.A. Bartholomew, Y. Hui, and E.L. Hegg. 2014. "Contributions of the [NiFe]- and [FeFe]-hydrogenase to H2 production in Shewanella oneidensis MR-1 as revealed by isotope ratio analysis of evolved H2." FEMS Microbiology Letters 352, no. 1:18-24. PNNL-SA-98025. doi:10.1111/1574-6968.12361
  • Moran J.J., C.G. Doll, H.C. Bernstein, R.S. Renslow, A.B. Cory, J.R. Hutchison, and S.R. Lindemann, et al. 2014. "Spatially tracking 13C labeled substrate (bicarbonate) accumulation in microbial communities using laser ablation isotope ratio mass spectrometry." Environmental Microbiology Reports 6, no. 6:786-791. PNNL-SA-97766. doi:10.1111/1758-2229.12211


  • Lindemann S.R., J.J. Moran, J.C. Stegen, R.S. Renslow, J.R. Hutchison, J.K. Cole, and A. Dohnalkova, et al. 2013. "The Epsomitic Phototrophic Microbial Mat of Hot Lake, Washington: Community Structural Responses to Seasonal Cycling." Frontiers in Microbiology 4. PNNL-SA-96936. doi:10.3389/fmicb.2013.00323
  • Moran J.J., C.J. Ehrhardt, J.H. Wahl, H.W. Kreuzer, and K.L. Wahl. 2013. "Integration of stable isotope and trace contaminant concentration for enhanced forensic acetone discrimination." Talanta 116. PNNL-SA-93211. doi:10.1016/j.talanta.2013.07.015


  • Kelly J.F., R.L. Sams, T.A. Blake, M.K. Newburn, J.J. Moran, M.L. Alexander, and H.W. Kreuzer. 2012. "A Capillary Absorption Spectrometer for Stable Carbon Isotope Ratio (13C/12C) Analysis in Very Small Samples." Review of Scientific Instruments 83, no. 2:Article No. 023101. PNNL-SA-81307. doi:10.1063/1.3680593
  • Kreuzer H.W., J. Horita, J.J. Moran, B. Tomkins, D.B. Janszen, and A.J. Carman. 2012. "Stable Carbon and Nitrogen Isotope Ratios of Sodium and Potassium Cyanide as a Forensic Signature." Journal of Forensic Sciences 57, no. 1:75-79. PNNL-SA-72316. doi:10.1111/j.1556-4029.2011.01946.x
  • Moran J.J., H.W. Kreuzer, A.J. Carman, J.H. Wahl, and D.C. Duckworth. 2012. "Multiple stable isotope characterization as a forensic tool to distinguish acid scavenger samples." Journal of Forensic Sciences 57, no. 1:60-63. PNNL-SA-74537. doi:10.1111/j.1556-4029.2011.01959.x


  • Harvey S.D., K.H. Jarman, J.J. Moran, C.M. Sorensen, and B.W. Wright. 2011. "Characterization of Diesel Fuel by Chemical Separation Combined with Capillary Gas Chromatography (GC) Isotope Ratio Mass Spectrometry (IRMS)." Talanta 99. PNNL-SA-83088. doi:10.1016/j.talanta.2012.05.049
  • Moran J.J., M.K. Newburn, M.L. Alexander, R.L. Sams, J.F. Kelly, and H.W. Kreuzer. 2011. "Laser ablation isotope ratio mass spectrometry for enhanced sensitivity and spatial resolution in stable isotope analysis." Rapid Communications in Mass Spectrometry 25, no. 9:1282-1290. PNNL-SA-77914. doi:10.1002/rcm.4985


  • Colburn H.A., D.S. Wunschel, H.W. Kreuzer-Martin, J.J. Moran, K.C. Antolick, and A.M. Melville. 2010. "Analysis of Carbohydrate and Fatty Acid Marker Abundance in Ricin Toxin Preparations for Forensic Information." Analytical Chemistry 82, no. 14:6040-6047. PNNL-SA-70231.

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