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The University of Texas
Marine Science Institute
750 Channel View Drive
Port Aransas, TX 78373
Phone: 361-749-6711

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James W McClelland

Department of Marine Science

Land-Sea Coupling, Coastal Ecosystem Dynamics, Biogeochemistry


Phone: 361-749-6756

Office Location

Postal Address

Ph.D., Boston University (1998)
B.S., University of Washington (1991)

Research Interests

Land-Sea Coupling/Coastal Ecosystem Dynamics/Biogeochemistry

Effects of human activity on water, carbon, and nutrient fluxes from land to sea; responses of estuarine and coastal food webs to changes in land-derived resources; use of stable isotopes and other natural tracers to follow water and water-borne constituents across the land-sea interface.

Environmental changes as a consequence of human activity, including changes in land use, land cover, and global warming, provide the context for much of my work. These changes are having a profound influence on the transport of water and water-borne constituents from land to sea. In turn, changes in the fluxes of water, carbon, and nutrients to estuaries and the coastal ocean are altering fundamental ecosystem properties such as primary production and food web structure.

Changes in land-sea fluxes have broader implications as well, including alteration of the global carbon budget and potential impacts of freshwater inputs on global ocean circulation and climate. To identify and explore changes in land-sea coupling I use a wide variety of approaches including analysis of historic data sets, field studies of biogeochemical cycling and constituent transport, and modeling. In my field studies, I frequently take advantage stable isotopes and other natural markers to track the fate of water, organic matter, and nutrients from land through estuarine and marine systems.

Armstrong, C.T., D.L. Erdner, J.W. McClelland, M.P. Sanderson, D.M. Anderson, C.H. Gobler, and J.L. Smith.  2018.  Impact of nitrogen chemical form on the isotope signature and toxicity of a marine dinoflagellate.  Marine Ecology Progress Series 602:63-76, doi:10.3354/meps12619.

Burke, A., T.M. Present, G. Paris, E.C.M. Rae, B.H. Sandilands, J. Gallardet, B. Peucker-Ehrenbrink, W.W. Fischer, J.W. McClelland, R.G.M. Spencer, B.M. Voss, and J.F. Adkins.  2018.  Sulfur isotopes in rivers: Insights into global weathering budgets, pyrite oxidation, and the modern sulfur cycle.  Earth and Planetary Science Letters 496:168-177, doi:10.1016/j.epsl.2018.05.022.

Griffin, C.G., J.W. McClelland, K.E. Frey, G. Fiske, and R.M. Holmes.  2018.  Quantifying CDOM and DOC in major Arctic rivers during ice-free conditions using Landsat TM and ETM+ data.  Remote Sensing of Environment 209:395-409, doi:10.1016/j.rse.2018.02.060.

Harris, C.M., N.D. McTigue, J.W. McClelland, and K.H. Dunton.  2018.  Do high Arctic coastal foods webs rely on a terrestrial carbon subsidy? Food Webs, doi:10.1016/j.fooweb.2018.e00081.

Bishop, K.A., J.W. McClelland, and K.H. Dunton.  2017.  Freshwater contributions and nitrogen sources in a South Texas estuarine ecosystem: A time-integrated perspective from stable isotopic ratios in the eastern oyster (Crassostrea virginica).  Estuaries and Coasts, doi:10.1007/s12237-017-0227-0 (11 pages).

Harris, C.M., J.W. McClelland, T.L. Connelly, B.C. Crump, and K.H. Dunton.  2017.  Salinity and temperature regimes in eastern Alaskan Beaufort Sea lagoons in relation to source water contributions.  Estuaries and Coasts 40:50-62, doi:10.1007/s12237-016-0123-z.

Lehn, G.O., A.D. Jacobson, T.A. Douglas, J.W. McClelland, A.J. Barker, and M.S. Khosh.  2017.  Constraining seasonal active layer dynamics and chemical weathering reactions occurring in North Slope Alaskan watersheds with major ion and isotope (δ34SSO4, δ13CDIC, 87Sr/86Sr, δ44/40Ca, and δ44/42Ca) measurements.  Geochimica et Cosmochimica Acta 217:399-420, doi: 10.1016/j.gca.2017.07.042.

Jones, A.E., B.R. Hodges, J.W. McClelland, A.K. Hardison, and K.B. Moffett.  2017.  Residence time-based classification of surface water systems.  Water Resources Research 53, doi:10.1002/2016WR019928 (18 pages).

Khosh, M.S., J.W. McClelland, A.D. Jacobson, T.A. Douglas, A.J. Barker, and G.O. Lehn.  2017.  Seasonality of dissolved nitrogen from spring melt to fall freeze-up in Alaskan Arctic tundra and mountain streams.  Journal of Geophysical Research – Biogeosciences, 122, doi:10.1002/2016JG003377 (20 pages).

Abbot, B.W. et al. (106 authors).  2016.  Biomass offsets little or none of permafrost carbon release from soils, streams, and wildfire: an expert assessment.  Environmental Research Letters 11, 034014, doi:10.1088/1748-9326/11/3/034014 (13 pages).

Mann, P.J., R.G.M. Spencer, P.J. Hernes, J. Six, G.R. Aiken, S.E. Tank, J.W. McClelland, K.D. Butler, R.Y. Dyda, and R.M. Holmes.  2016.  Pan-Arctic trends in terrestrial dissolved organic matter from optical measurements.  Frontiers in Earth Science 4, Article 25, doi:10.3389/feart.2016.00025 (18 pages). 

McClelland, J.W., R.M. Holmes, B.J. Peterson, P.A. Raymond, R.G. Striegl, A.V. Zhulidov, S.A. Zimov, N. Zimov, S.E. Tank, R.G.M. Spencer, R. Staples, T.Y. Gurtovaya, C.G. Griffin.  2016.  Particulate organic carbon and nitrogen export from major Arctic rivers.  Global Biogeochemical Cycles 30, doi:10.1002/2015GB005351 (15 pages).

Mohan, J.A., S.D. Smith, T.L. Connelly, E.T. Attwood, J.W. McClelland, S.Z. Herzka, and B.D. Walther.  2016. Tissue-specific isotope turnover and discrimination factors are affected by diet quality and lipid content in an omnivorous consumer.  Journal of Experimental Marine Biology and Ecology 479:35-45, doi:10.1016/j.jembe.2016.03.002.

Mohan, S.D., T.L. Connelly, C.M. Harris, K.D. Dunton, and J.W. McClelland.  2016.  Seasonal trophic linkages in Arctic marine invertebrates assessed via fatty acids and compound-specific stable isotopes.  Ecosphere 7, e01429, doi:10.1002/ecs2.1429 (21 pages).

Mohan, S.D., J.A. Mohan, T.L. Connelly, B.D. Walther, and J.W. McClelland.  2016.  Fatty-acid biomarkers and tissue-specific turnover: validation from a controlled feeding study in juvenile Atlantic croaker Micropogonias undulatusJournal of Fish Biology, doi:10.1111/jfb.13099 (20 pages).

Tank, S.E., R.G. Striegl, J.W. McClelland, and S.V. Kokelj.  2016.  Multi-decadal increases in dissolved organic carbon and alkalinity flux from the Mackenzie drainage basin to the Arctic Ocean.  Environmental Research Letters 11, 0540154, doi:10.1088/1748-9326/11/5/054015 (10 pages).

Connelly, T.L., J.W. McClelland, B.C. Crump, C.T.E. Kellogg, and K.H. Dunton.  2015.  Seasonal changes in the quantity and composition of suspended particulate organic matter in lagoons of the Alaskan Beaufort Sea. Marine Ecology Progress Series 527:31-45.

Elhassan, A., H. Xie, A.A. Al-othman, J. McClelland, H.O. Sharif.  2015.  Water quality modelling in the San Antonio River Basin driven by radar rainfall data.  Geomatics, Natural Hazards, and Risk, doi:10.1080/19475705.2015.1009500 (18 pages).

Fuiman, L.A., T.L. Connelly, S.K. Lowerre-Barbieri, and J.W. McClelland.  2015.  Egg boons: central components of marine fatty acid foods webs. Ecology 96(2):362-372.

McClelland, J.W., S.E. Tank, R.G.M. Spencer, and A.I. Shiklomanov.  2015.  Coordination and sustainability of river observing activities in the Arctic. Arctic 68, Suppl. 1, doi:10.14430/arctic4448 (10 pages).

Stubbins, A., R.G.M. Spencer, P.J. Mann, R.M. Holmes, J.W. McClelland, J. Niggemann, and T. Dittmar.  2015. Utilizing colored dissolved organic matter to derive dissolved black carbon export by arctic river.  Frontiers in Earth Science 3, Article 63, doi:10.3389/feart.2015.00063 (11 pages).

Tavakoly, A.A., D.R. Maidment, J.W. McClelland, T. Whiteaker, Z.-L. Yang, C. Griffin, C.H. David, and L. Meyer. 2015.  A GIS framework for regional modeling of riverine nitrogen transport: Case study, San Antonio and Guadalupe Basins. Journal of the American Water Resources Association, doi:10.1111/1752-1688.12355 (15 pages).

Whitefield, J., P. Winsor, J. McClelland, and D. Menemenlis.  2015.  A new river discharge and river temperature climatology data set for the pan-Arctic region. Ocean Modelling 88:1-15.

Barker, A.J., T.A. Douglas, A.D. Jacobson, J.W. McClelland, A.G. Ilgen, M.S. Khosh, G.O. Lehn, and T.P. Trainor. 2014.  Late season mobilization of trace metals in two small Alaskan arctic watersheds as a proxy for landscape scale permafrost active layer dynamics. Chemical Geology 381:180-193.

McClelland, J.W., A. Townsend-Small, R.M. Holmes, F. Pan, M. Stieglitz, M. Khosh, and B.J. Peterson.  2014.  River export of nutrients and organic matter from the North Slope of Alaska to the Beaufort Sea, Water Resources Research 50, doi:10.1002/2013WR014722 (16 pages).

Turner, E.L., D.A. Bruesewitz, R.F. Mooney, P.A. Montagna, J.W. McClelland, A. Sadovksi, and E.J. Buskey.  2014. Comparing performance of five nutrient phytoplankton zooplankton (NPZ) models in coastal lagoons.  Ecological Modelling 277:13-26.

Kicklighter, D.W., D.J. Hayes, J.W. McClelland, B.J. Peterson, A.D. McGuire, and J.M. Melillo.  2013.  Insights and issues with simulating terrestrial DOC loading of Arctic river networks.  Ecological Applications 23:1817-1836.

Amon, R.M.W., A.J. Rinehart, S. Duan, P. Louchouarn, A. Prokushkin, G. Guggenberger, D. Bauch, C. Stedmon, P.A. Raymond, R.M. Holmes, J.W. McClelland, B.J. Peterson, S. A. Walker, and A.V. Zhulidov.  2012.  Dissolved organic matter sources in large Arctic rivers.  Geochimica et Cosmochimica Acta 94:217-237.

Holmes, R.M., J.W. McClelland, B.J. Peterson, S.E. Tank, E. Bulygina, T.I. Eglinton, V.V. Gordeev, T.Y. Gurtovaya, P.A. Raymond, D.J. Repeta, R. Staples, R. Striegl, A.V. Zhulidov, and S.A. Zimov.  2012.  Seasonal and annual fluxes of nutrients and organic matter from large rivers to the Arctic Ocean and surrounding seas.  Estuaries and Coasts 35:369–382, doi:10.1007/s12237-011-9386-6.

McClelland, J.W., R.M. Holmes, K.H. Dunton, and R.W. Macdonald.  2012.  The Arctic Ocean Estuary.  Estuaries and Coasts 35:353-368, doi:10.1007/s12237-010-9357-3.

Mooney, R.F., and J.W. McClelland.  2012.  Watershed export events and ecosystem responses in the Mission-Aransas National Estuarine Research Reserve, south Texas.  Estuaries and Coasts 35:1468-1485, DOI 10.1007/s12237-012-9537-4.

Tank, S. E., P. A. Raymond, R. G. Striegl, J. W. McClelland, R. M. Holmes, G. J. Fiske, and B. J. Peterson.  2012.  A land-to-ocean perspective on the magnitude, source and implication of DIC flux from major Arctic rivers to the Arctic Ocean.  Global Biogeochem. Cycles 26, GB4018, doi:10.1029/2011GB004192 (15 pages).

Tank, S.E., M. Manizza, R.M. Holmes, J.W. McClelland, and B.J. Peterson.  2012.  The processing and impact of riverine nutrients and organic matter in the near- and offshore Arctic Ocean.  Estuaries and Coasts 35:401–415, doi:10.1007/s12237-011-9417-3.

Tank, S. E., K. E. Frey, R. G. Striegl, P. A. Raymond, R. M. Holmes, J. W. McClelland, and B. J. Peterson.  2012. Landscape-level controls on dissolved carbon flux from diverse catchments of the circumboreal.  Global Biogeochem. Cycles 26, GB0E02, doi:10.1029/2012GB004299 (15 pages).

Yi, Y., J.J. Gibson, L.W. Cooper, J.-F. Hélie, S.J. Birks, J.W. McClelland, R.M. Holmes, and B.J. Peterson.  2012. Isotopic signals (18O, 2H, 3H) of six major rivers draining the pan-Arctic watershed, Global Biogeochem. Cycles 26, GB1027, doi:10.1029/2011GB004159 (9 pages).

Manizza, M., M.J. Follows, S. Dutkiewicz, D. Menemenlis, J.W. McClelland, C.N. Hill, B.J. Peterson, and R.M. Key. 2011.  A model of the Arctic Ocean carbon cycle, J. Geophys. Res. 116, C12020, doi:10.1029/2011JC006998 (19 pages).

McGuire, A.D., D.J. Hayes, D.W. Kicklighter, M. Manizza, Q. Zhuang, M. Chen, M.J. Follows, K.R. Gurney, J.W. McClelland, J.M. Melillo, B.J. Peterson, and R.G. Prinn.  2010.  An analysis of the carbon balance of the Arctic basin from 1997 to 2006.  Tellus, doi:10.1111/j.1600-0889.2010.00497.x (20 pages).

Townsend-Small, A., J.W. McClelland, R.M. Holmes and B.J. Peterson.  2010.  Seasonal and hydrologic drivers of dissolved organic matter and nutrients in the upper Kuparuk River, Alaskan Arctic.  Biogeochemistry, doi:10.1007/s10533-010-9451-4 (16 pages). 

Crump, B.C., B.J. Peterson, P.A. Raymond, R.M.W. Amon, A. Rinehart, J.W. McClelland, and R.M. Holmes.  2009. Circumpolar synchrony in big river bacterioplankton.  Proceedings of the National Academy of Sciences 106:21208-21212.

Manizza, M., M.J. Follows, S. Dutkiewicz, J.W. McClelland, D. Menemenlis, C.N. Hill, A. Townsend-Small, and B.J. Peterson.  2009.  Modeling transport and fate of riverine dissolved organic carbon in the Arctic Ocean.  Global Biogeochem. Cycles 23, GB4006, doi:10.1029/2008GB003396 (10 pages).

Frey, K.E. and J.W. McClelland.  2009.  Impacts of permafrost degradation on arctic river biogeochemistry.  Hydrological Processes, 23:169-182.

Cooper, L.W., J.W. McClelland, R.M. Holmes, P.A. Raymond, J.J. Gibson, C.K. Guay, and B.J. Peterson.  2008. Flow-weighted values of runoff tracers (d18O, DOC, Ba, alkalinity) from the six largest Arctic rivers.  Geophys. Res. Lett. 35, L18606, doi:10.1029/2008GL035007 (5 pages).

Fox, S.E., E. Stieve, I. Valiela, J. Hauxwell, and J. McClelland.  2008.  Macrophyte abundance in Waquoit Bay: Effects of Land-derived nitrogen loads on seasonal and multi-year biomass patterns.  Estuaries and Coasts 31:532-541.

  • 2010 UT-Austin College of Natural Sciences Teaching Excellence Award 
  • 1998-1999 NSF-NATO Postdoctoral Fellowship in Science and Engineering
  • 1996-1997 Outstanding Teaching Fellow Award, Boston University
  • 1994-1996 Waquoit Bay Fellowship, Boston University
  • 1994 Arthur G. Humes Alumni Award, Boston University