Dr. Jack Morgan Research LeaderPlant Physiologist USDA - ARS Crops Research Laboratory 1701 Center Ave. Fort Collins, CO 80526 PHONE: Ft. Collins,CO:  970-492-7121 Contact here on M-W-T-F  Cheyenne, WY:   307-772-2433 ext. 103  on Tuesday's FAX:  (970)492-7160  Jack.Morgan@ars.usda.gov Degrees    Research   Publications

DEGREES:

 

B.S.	New Mexico State University	1975
M.S.	University of Georgia	1978
Ph.D.	University of Georgia	1981

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RESEARCH INTERESTS:

Research interests in photosynthesis, plant/soil water relations, and physiological plant ecology of native grasslands.  His major two areas of research are understanding the effects of global climate change on western rangelands, and evaluating the impacts of management practices on the health of rangelands, particularly in regards to C cycling.  Increases in atmospheric CO2 concentrations have important implications for rangelands as they are predicted to cause major changes in the global climate, and may already be affecting weather patterns and productivity of western rangelands.  Increase in CO2 will also impact rangelands through their direct effects of photosynthesis, growth, water relations, N metabolism and forage quality, and secondarily through effects on soil biology and mineral cycling.  Dr. Morgan has been engaged in CO2 enrichment research for several years with a cadre of scientists from other ARS research units and from Colorado State University, the University of Northern Colorado, and the University of Colorado.  The goal of these studies is to better understand how future CO2-enriched atmospheres will affect the ecology and sustainability of Great Plains grasslands, and to use that knowledge to develop management practices that will be appropriate for future environments.  The C cycling work has been geared to evaluating how different grazing practices affect plant ecology, biodiversity, and ultimately, the C exchange and budget of rangelands.  This work has been conducted in shortgrass steppe and northern mixed prairie, but plans are underway to take this work to sagebrush steppe regions in Wyoming.

 Dr. Morgan is also the Research Leader of the USDA-ARS Rangeland Resources Research Unit, headquartered at the High Plains Grasslands Research Station in Cheyenne, Wyoming, with labs and offices at the Crops Research Lab in Fort Collins, CO and the Central Plains Experimental Range near Nunn, CO.  This ARS research unit consists of an interdisciplinary group of scientists and support staff with expertise in plant and soil science, ecology, hydrology and range science, and is engaged in studies to understand various aspects of the ecology of western rangelands for purposes of providing ranchers, public land managers, state and federal governmental entities, other scientists and the public information on the functioning of these lands and tools for their wise management.   Dr. Morgan is also a co-PI on the National Science Foundation funded Shortgrass Steppe Long Term Ecological Research Project, headquartered at Colorado State University, and is an affiliate faculty member in the Department of Renewable Resources at the University of Wyoming and the Crops and Soils Department at Colorado State University.   

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Selected Publications:

2008

Burke, I.C., Lauenroth, W.K., Antolin, M.F., Derner, J.D., Milchunas, D.G., Morgan, J.A., Stapp, P. 2008. The future of the shortgrass steppe. In:  W.K. Lauenroth and I.C. Burke (eds.). Ecology of the shortgrass steppe: A long‐term perspective. Oxford University Press, Oxford, England. pp. 484‐510.

Lauenroth, W.K., Burke, I.C., Morgan, J.A. 2008. The shortgrass steppe: The region and research sites. In: W.K. Lauenroth and I.C. Burke (eds.). Ecology of the shortgrass steppe: A long‐term perspective. Oxford University Press, Oxford, England. pp. 3‐13.

Lauenroth, W.K., Milchunas, D.G., Sala, O.E., Burke, I.C., and Morgan, J.A. 2008. Net primary production in the shortgrass steppe: A long‐term perspective. Oxford University Press, Oxford, England. pp. 270‐305.

Tony Svejcar, Raymond Angell, James A. Bradford, William Dugas, William Emmerich,Albert B. Frank, Tagir Gilmanov, Marshall Haferkamp, Douglas A. Johnson, Herman Mayeux, Pat Mielnick, Jack Morgan, Nicanor Z. Saliendra, Gerald E. Schuman,Phillip L. Sims, and Kereith Snyder. 2008. Carbon Fluxes on North American Rangelands. Rangeland Ecol Manage 61:465–474

Morgan, J.A., J.D. Derner, D.G. Milchunas, and E. Pendall.  Management implications of global change for Great Plains rangelands. Rangelands 30:18-22. 2008

Norton, U., Mosier, A.R., Morgan, J.A., Derner, J.D., Ingram, L.J. and P.D. Stahl. Moisture pulses, trace gas emissions and soil C and N in cheatgrass and native grass-dominated sagebrush-steppe in Wyoming, USA. Soil Biology & Biochemistry 40:1421-1431. 2008.

Ayers, E., D.H. Wall, B.L. Simmons, C.B. Field, D. Milchunas, J.A. Morgan and J. Roy. 2008. Belowground grassland herbivores are resistant to elevated atmospheric CO2 concentrations in grassland ecosystems. Soil Biology and Biochemistry 40:978-985.

Kandeler, E., A.R. Mosier, J.A. Morgan, D.G. Milchunas, J.Y. King, S. Rudolph, and D. Tscherko. 2008. Transient elevation of carbon dioxide modifies the microbial community composition in a semi-arid grassland. Soil Biology and Biochemistry 40:162-171.

2007

Körner, C., J.A. Morgan and R. Norby. 2007. CO2 fertilization: When, where, and how much? In: Canadell JG, Pataki DE, Pitelka LF (eds) Terrestrial Ecosystems in a Changing World. The IGBP Series. pp 9-22. Springer, Berlin.

Wylie, B.K., E.A. Fosnight, T.G. Gilmanov, A.B. Frank, J.A. Morgan, M.R. Haferkamp and T.P. Meyers. 2007. Adaptive Data-Driven Models for Estimating Carbon Fluxes in the Northern Great Plains. Remote Sensing of Environment 106:399-413.

Morgan, J.A., D.G. Milchunas, D.R. LeCain, M.S. West and A. Mosier. 2007. Carbon dioxide enrichment alters plant community structure and accelerates shrub growth in the shortgrass steppe. Proceedings of the Natl Academy of Sciences, 104(37):14724-14729.

2006

LeCain, D.L., J.A. Morgan, D.G. Milchunas, A.R. Mosier, J.A. Nelson and D.P. Smith. 2006. Root biomass of individual species, and root size characteristics after five years of CO2 enrichment on native shortgrass steppe. Plant and Soil 279:219-228.

2005

Milchunas, D.G., A.R. Mosier, J.A. Morgan, D.R. LeCain, J.Y. King and J.Y. Nelson. 2005. Root production and tissue quality in a shortgrass steppe exposed to elevated CO2: Using a new ingrowth method. Plant and Soil 268:111-122.

Pendall, E., J.Y. King, A.R. Mosier, J. Morgan and D. Milchunas. 2005. Stable isotope constraints on net ecosystem production under elevated CO2. In: L.B. Flanagan, J.R. Ehleringer and D.E. Pataki (eds) Stable Isotopes and Biosphere-Atmospheric Interactions: Processes and Biological Controls. pp 182-198. Elsevier Inc., San Diego, CA.

Milchunas, D.G., A.R. Mosier, J.A. Morgan, D.R. LeCain, J.Y King and J.A. Nelson. 2005. Elevated CO2 and defoliation effects on a shortgrass steppe: forage quality versus quantity for ruminants. Agriculture, Ecosystems and Environment 111:166-184.

Milchunas, D.G., J.A. Morgan, A.R. Mosier and D.R. LeCain. 2005. Root dynamics and demography in shortgrass steppe under elevated CO2, and comments on minirhizotron methodology. Global Change Biology 11:1837-1855.

Gilmanov, T.G., L.L. Tieszen, B.K. Wylie, L.B. Flanagan, A.B. Frank, M.R. Haferkamp, T.P. Meyers and J.A. Morgan. 2005. Integration of CO2 flux and remotely sensed data for primary production and ecosystem respiration analyses in the Northern Great Plains: Potential for quantitative spatial extrapolation. Global Ecology and Biogeography 14:271-292.

Derner, J.D., G.E. Schuman, M. Jawson, S.R. Shafer, J.A. Morgan, H.W. Polley, G.B. Runion, S.A. Prior, H.A. Torbert, H.H. Rogers, J. Bunce, L. Ziska, J.W. White, A.J. Franzluebbers, J.D. Reeder, R. Venterea and L.A. Harper. USDA-ARS Global Change Research on Rangelands and Pasturelands. Rangelands 27:36-42.

2004

Nelson, J.A., J.A. Morgan, D.R. LeCain, A.R. Mosier, D.G. Milchunas, and B.A. Parton. 2004. Elevated CO2 increases soil moisture and enhances plant water relations in a long-term field study in semi-arid shortgrass steppe of Colorado. Plant and Soil 259:169-179.

Morgan, J.A., A.R. Mosier, D.G. Milchunas, D.R. LeCain, J.A. Nelson and W.J. Parton.  2004.  CO2 enhances productivity, alters species composition, and reduces forage digestibility of shortgrass steppe vegetation.  Ecological Applications 14:208-219.

Reeder, J.D., G.E. Schuman, J.A. Morgan, and D.R. LeCain.  2004.  Response of organic and inorganic carbon and nitrogen stocks to long-term  grazing of the shortgrass steppe.  Environmental Management 10.1007/s00267-003-9106-5.

Pendall , A.R. Mosier, and J.A. Morgan.  2004.   Rhizodeposition stimulated by elevated CO2 in a semi‑arid grassland.  New Phytologist 162:447-458

Reeder, J.D., G.E. Schuman, J.A. Morgan and D.R. LeCain. 2004. Response of organic and inorganic carbon and nitrogen stocks to long-term grazing of the shortgrass steppe.  Environmental Management 33:485-495.

King, J.Y., A.R. Mosier, J.A. Morgan, D.R. LeCain, D.G. Milchunas and W.J. Parton. 2004. Plant nitrogen dynamics in shortgrass steppe under elevated atmospheric CO2. Ecosystems 7:147-160.

Milchunas, D.G., J.Y. King, A.R. Mosier, J.C. Moore, J.A. Morgan, M.H. Quirk and J.R. Slusser. 2004. UV radiation effects on plant growth and forage quality in a shortgrass steppe ecosystem. Photochemistry and Photobiology 79:404-410.

Pendall E., A.R. Mosier and J.A. Morgan. 2004. Rhizodeposition stimulated by elevated CO2 in a semi arid grassland. New Phytologist 162:447-458.

Morgan, J.A., D.E. Pataki, C. Korner, H. Clark, S.J. DelGrosso, J.M. Grunzewig, A.K. Knapp, A.R. Mosier, P.C.D. Newton, P.A. Niklaus, J.B. Nippert, R.S. Nowak, W.J. Parton, H.W. Polley and M.R. Shaw. 2004. Water relations in grassland and desert ecosystems to elevated atmospheric CO2. Oecologia 140:11-25.

Liebig, M.A., J.A. Morgan, J.D. Reeder, B.H. Ellert, H.T. Gollany and G.E. Schuman. 2004. Greenhouse Gas Contributions and Mitigation Potential of Agricultural Practices in Northwestern USA and Western Canada. ASA Meetings (abstract).

2003

Ferretti, D.F., E. Pendall, J.A. Morgan, J.A. Nelson, D.R. LeCain and A.R. Mosier.  2003.  Partitioning evapotranspiration fluxes from a Colorado grassland using stabel isotopes: seasonal variations and implication for elevated atmospheric CO[1] 2.  Plant and Soil 254:291-303. 

Pendall, E., S. Del Grosso, J.Y. King, D.R. LeCain, D.G. Milchunas, J.A. Morgan, A.R. Mosier, D.S. Ojima, W.A. Parton, P.P. Tans, and J.W.C. White.  2003.  Elevated atmospheric CO2 effects and soil water feedbacks on soil respiration components in a Colorado grassland.  Global Biogeochemical Cycles 17:1-13.

LeCain, D.R., J.A. Morgan, A.R. Mosier and J.A. Nelson.  2003.  Soil and plant water relations, not photosynthetic pathway, primarily influence photosynthetic responses in a semi-arid ecosystem under elevated CO2.  Annals of Botany 92:41-52.           

Mosier, A.R., E. Pendall, and J.A. Morgan.  2003.  Soil-atmosphere exchange of CH4, CO2, NOx, and N2O in the Colorado Shortgrass steppe following five years of elevated CO2 and N fertilization.  Atmospheric Chemistry and Physics Discussions 3:2691-2706.

King, J., D. Milchunas, A. Mosier, Moore, J. Morgan, Slusser. 2003. Initial Impacts of Altered UVB Radiation on Plant Growth and Decomposition in Shortgrass Steppe. International Society for Optical Engineering Annual Meeting.

2002

Morgan, J.A. 2002. Looking beneath the Surface. Science 298: 1903-1904.

Lecain, D.R., J.A. Morgan, G.S. Schuman and J.D. Reeder, and R.H. Hart. 2002. Carbon exchange rates and species composition of grazed pastures and exclosures in the shortgrass steppe of Colorado. Agriculture, Ecosystems and Environment 93:421-435.

Gill, R.A., Kelly, R.H., W.J. Parton, K.A. Day, R.B. Jackson, J.A. Morgan, J.M.O. Scurlock, L.L. Tieszen, J. van de Castle, D.S. Ojima, and X.S. Zhang. 2002. Using simple environmental variables to estimate belowground productivity in grasslands. Global Ecology and Biogeography 11(1):79-86.

Mosier, A.R., J.A. Morgan, J.Y. King, D. LeCain and D.G. Milchunas. 2002. Soil-atmosphere exchange of CH4, CO2, NOx, and N2O in the Colorado Shortgrass Steppe under Elevated CO2. Plant and Soil 240:201-211.

Derner, J.D., D.T. Booth, J.A. Morgan, G.E. Schuman and J.D. Reeder.  2002. High Plains Grasslands Research Station - Changing to meet the challenges of a new century. Cow Country 130:4-5

2001

Morgan, J.A., A.R. Mosier, D.R. LeCain, W.J. Parton and D.G. Milchunas. 2001. Elevated CO2 enhances productivity and the C/N ratio of grasses in the Colorado shortgrass steppe. Proceedings of the XIX International Grassland Congress. pp 981-982. Brazilian Society of Animal Husbandry, Sao Pedro, Sao Paulo, Brazil.

Morgan, J.A., P.C.D. Newton, J. Nösberger and C.E. Owensby. 2001. The influence of rising atmospheric CO2 on grassland ecosystems. Proceedings of the XIX International Grassland Congress. pp 973-980. Brazilian Society of Animal Husbandry, Sao Pedro, Sao Paulo, Brazil..

Reeder, J.D., G.E. Schuman, J.A. Morgan, D.R. LeCain and R.H. Hart. 2001. Impact of grazing management strategies on carbon sequestration in a semi-arid rangeland, USA. Proceedings of the XIX International Grassland Congress. pp 211-213. Brazilian Society of Animal Husbandry, Sao Pedro, Sao Paulo, Brazil. XIX International Grassland Congress.

Morgan, J.A., R.H. Skinner, and J.D. Hanson. 2001. Nitrogen and CO2 affect regrowth and biomass partitioning differently in forages of three functional groups. Crop Science 41:78-86.

Morgan, J.A., D.R. LeCain, A.R. Mosier, and D.G. Milchunas.  2001.  Elevated CO2 enhances water relations and productivity and affects gas exchange in C3 and C4 grasses of the Colorado Shortgrass Steppe.  Global Change Biology 7:451-466.

Schuman, G.E., D.R. LeCain, J.D. Reeder, and J.A. Morgan. 2001. Carbon dynamics and sequestration of a mixed-grass prairie as influenced by grazing. pp. 67-75. In: R. Lal (ed.)Soil Carbon Sequestration and the Greenhouse Effect. Soil Sci. Soc. Am., Special Publ. No. 57. Soil Science Society of America, Madison, WI

2000

LeCain, D.R., J.A. Morgan, G.E. Schuman, J.D. Reeder, and R.H. Hart. 2000. Carbon exchange rates in grazed and ungrazed pastures of Wyoming. J. Range Management. 53: 199-206.

Parton, W.J., J.A. Morgan, R.H. Kelly and D. Ojima. 2000. Modeling soil C responses to environmental change in grassland systems. pp 371-398. In R.F. Follet, J.M. Kimble and R. Lal (eds) The Potential of U.S. Grazing Lands to Sequester Carbon and Mitigate the Greenhouse Effect, Lewis Publishers, New York.

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