Curriculum Vitae: David G. Williams

Last updated September 7, 2006

 

Department of Renewable Resources                 Tel: 307-766-2494

University of Wyoming                                         Fax: 307-766-6403

Laramie, WY 82071                                               Email: dgw@uwyo.edu

                    

 

Education

 

      BA - 1985              Botany, The University of Texas, Austin

      MS - 1988             Range Science, Texas A&M University, College Station

Thesis title: Extent and ecological significance of physiological integration among ramets within the bunchgrass Schizachyrium scoparium var. frequens. (Advisor Ð David D. Briske)

      PhD - 1992            Botany, Washington State University, Pullman

Dissertation title: Physiological ecology of the invasive grass Pennisetum setaceum on Hawaii. (Advisors Ð Richard N. Mack and R. Alan Black)

 

Areas of specialization

 

Stable isotope ecology, applied plant ecology, plant physiological ecology, plant water relations, carbon and water cycles in arid and semi-arid environments, ecology of plant invasions, global change ecology

 

Academic positions

 

      2002-present       Associate Professor, Departments of Renewable Resources and Botany,

                                          University of Wyoming

      2002-present       Adjunct Associate Professor, School of Renewable Resources,

                                          University of Arizona

      2002-present       Director, University of Wyoming Stable Isotope Facility,

                                          University of Wyoming

      2002-2003           Fulbright Research Fellow, Centre dÕEtudes Spatiales de la Biosphere,

                                          Toulouse, France

      2001-2002           Associate Professor, School of Renewable Natural Resources,

                                          University of Arizona

      1995-2001           Assistant Professor, School of Renewable Natural Resources,

                                          University of Arizona

1993-1995                 Postdoctoral Research Fellow, Department of Biology, University of Utah

      1988-1992           Teaching/Research Assistant, Departments of Botany and Biology,

                                          Washington State University

      1985-1988           Teaching/Research Assistant, Departments of Range Science and Biology,

                                          Texas A&M University

 

Honors and Awards

 

      Phi Kappa Phi, 1988

      Sigma Xi Graduate Research Award, 1990

      Biddulph Graduate Student Fellowship in Botany, Washington State University, 1991

      United States Department of Agriculture, National Research Initiative Competitive Grants Program, New Investigator Award, 1996

      United States Department of Agriculture, Group Honor Award for Excellence, 2001

      Fulbright Research Scholar Award for France, 2002-2003

 

Professional society memberships

 

      Ecological Society of America

      American Geophysical Union

      Society for Range Management

 

Grants and Contracts Awarded

 

Williams, D.G. Water use along a semi-arid riparian continuum. USDA-NRI, $97,242, 1996-1999.

Williams, D.G. Effect of grass invasion on soil carbon and nitrogen dynamics. University of Arizona Faculty Small Grant Program, $5,000, 1996-1997.

Williams, D.G. Alien grass invasion and ecosystem feedbacks in southern Arizona. Agricultural Experiment Station/Hatch. $38,640, 1996-1999.

Goodrich, D., D. Cooper, J.L. Dwyer, L. Hipps, T. Maddock, III, S. Moran., D.E. Myers, E. Njoku, J. Schieldge, D.I. Stannard, and D.G. Williams. Water resources management to sustain growth and riparian biodiversity: In-situ and remote measurements of riparian corridor evapotranspiration. NASA, $154,372, 1996-1998.

McPherson, G., M. McClaran, and D.G. Williams. An interactive computer instructional environment for interrelated courses. University of Arizona Teaching Center, $5,400, 1997-1998.

Leavitt, S., M.J. Ottman, A.D. Matthias, T.L. Thompson, D.G. Williams, and R.L. Roth. Elevated CO2 and limited water supply effects on carbon processes and sequestration in C4 grass. USDA-NRI, $505,700, 1997-2000.

Williams, D.G. Isotopic indicators of CO2 and H2O fluxes in semi-arid ecosystems. University of Arizona Research Development Funds competitive grant; $20,000, 1998-2000.

Leavitt, S. and D.G. Williams. Visiting scholar fund for the Institute for the Study of Planet Earth. University of Arizona, $1,312, 1998.

Goodrich, D. and D.G. Williams. Ephemeral channel deep recharge and evapotranspiration from near-channel vegetation. Cochise County, AZ, $70,163, 1998-2000.

Williams, D.G., K. Hultine, D.G. Goodrich. Isotope biohydrology of an ephemeral drainage. USGS/Water Resources Research Center competitive grant, $13,724, 1999-2000.

Webb, R.H., D. Meko, and D.G. Williams. Surface water/groundwater dependence of riparian trees: A synthetic dendrohydrology and ecophysiology study. USGS-Groundwater Project, $150,000, 1999-2002.

Williams, D.G., D.L. Dettman, S.W. Leavitt, T.A. Markow, C.M. del Rio. An isotope ratio mass spectrometer for the biological sciences at the University of Arizona. NSF, $189,000, 2000-2001. 

Weltzin, J., and D.G. Williams. Climate change, grass invasions, and woody plant dynamics in semi-arid savannas. USDA-NRI, $300,000, 2000-2003.

Williams, D.G. Interactions between mesquite and Lehmann lovegrass: geomorphic controls on plant and soil water balance. Agricultural Experiment Station/Hatch, $18,000, 2000-2003.

Williams, D.G. Integrated measurement and modeling of hydro-ecological resources in Morocco. $4,885, University of Arizona Faculty Small Grant Program, 2001-2002.

Goodrich, D., R. Scott, D.G. Williams, N. Grimm, M. Conklin, and J. Stromberg. San Pedro Riparian National Conservation Area Water Needs Study. $823,894, BLM-Upper San Pedro Partnership, 2001-2005.

Williams, D.G., D. Goodrich, R. Scott, and G. Lin. Relationship between hydrologic condition and plant transpiration and carbon exchange. $109,190 (year 1). 2001-2003. NSF-SAHRA Science and Technology Center.

Williams, D.G. Integrated measurement and modeling of hydro-ecological resources in semi-arid regions. $22,000. Fulbright Scholar Program, France. 2002-2003.

Williams, D.G. and S.E. Williams. Collaborative Isotopic Studies in Steppe Ecosystems of Inner Mongolia and Wyoming. $1,500. University of Wyoming, College of Agriculture Global Perspectives Grant. 2004.

Williams, D.G. Net carbon exchange and evapotranspiration in sagebrush steppe: response to extreme summer rainfall events. $8,000. Wyoming NASA Space Grant Consortium. 2004.

Williams, D.G. Collaborative Isotopic Studies in Steppe Ecosystems of Inner Mongolia and Wyoming. $1,035. University of Wyoming International Program Travel Grant. 2004.

Williams, D.G., M. Ben-David, R.O. Hall, C. Martinez del Rio and E. Pendall. Isotope ratio mass spectrometers for biological and environmental research and training at the University of Wyoming. $409,042 total, $270,042 external. NSF (DBI-0400752). 2004-2005.

Williams, D.G. Collaborative Research: Sensitivity of ecosystem processes to precipitation across a grassland to shrubland vegetation transition in the southwestern US. $224,000. NSF (DEB-0414680). 2004-2007.

Williams, D.G. Collaborative Research: Vulnerability of semi-arid grasslands to encroachment by woody plants: the role of grass invasions, seasonal precipitation, and soil type. $109,496. NSF (DEB-0417228). 2004-2007.

Williams, D.G. Travel Grant for BASIN

Williams, D.G. and E. Pendall. How will grassland ecosystems respond to rising CO2 and climate change? $130,000. USDA-ARS subcontract cooperative agreement. 2004-2009.

Sharma, S. and D.G. Williams. Volcanic degassing in Yellowstone National Park: An un-tapped research opportunity for studying effects of elevated CO2 on coniferous forest. $7,500. University of Wyoming Faculty Grant-in-Aid. 2006-2007.

 

 

Publications (*students and postdocs mentored by Williams)

 

Book chapters

 

Ehleringer, J.R., R.D. Evans, and D. Williams. 1998. Assessing sensitivity to change in desert ecosystems - a stable isotope approach. Pages 223-237.  In H. Griffiths (ed.), Stable Isotopes Integration of Biological, Ecological, and Geochemical Processes.  BIOS Scientific Publ., Oxford.

Williams, D.G., G.R. McPherson, and J.F. Weltzin. 1999. Stress in Wildland plants: Implications for ecosystem structure and function. Pages 907-929.  In M. Pessarakli (ed.). Handbook of plant and crop stress: second edition. Marcel Dekkar, Inc., New York.

Williams, D.G. and K.A. Snyder. 2003. Responses of woody plants to heterogeneity of soil water in arid and semiarid environments. Pages 28-46. In J. Weltzin and G. McPherson (eds), Changing precipitation regimes and terrestrial ecosystems. University of Arizona Press, Tucson.

Goodrich, D.C., D.G. Williams, C.L. Unkrich, J.F. Hogan, R.L. Scott, K.R. Hultine, D. Pool, A.L. Coes, and S. Miller. 2004. Comparison of methods to estimate ephemeral channel recharge, Walnut Gulch, San Pedro River Basin, Arizona, In Groundwater Recharge in a Desert Environment: The Southwestern United States, edited by J.F. Hogan, F.M. Phillips, and B.R. Scanlon, Water Science and Applications Series, vol. 9, American Geophysical Union, Washington, D.C., pp. 77-99.

*Yepez E.A. and D.G. Williams. Precipitation pulses and ecosystem carbon and water exchange in arid and semiarid environments. In Biophysical plant ecology: perspectives and trends, ed. E. de la Barrera. UC Press, Berkeley CA. (submitted).

Williams, D.G. and R. Scott. Vegetation-hydrology interactions: Dynamics of riparian plant water use along the San Pedro River, Arizona. In Stromberg, J. and B. Tellman (eds) Riparian area conservation and ecology in a semi-arid region: the San Pedro River example. (in press).

Williams, D.G., R.D. Evans and J.R. Ehleringer. Applications of stable isotope measurements for early-warning detection of ecological change. In T.E. Dawson and R. Siegwolf (eds), Isotopes as tracers of ecological change. Elsevier Academic Press. (in review).

Hemming, D., N. Loader, A. Marca , I. Robertson, D. Williams, L. Wingate, D. Yakir. The future of large-scale isotope networks. In T.E. Dawson and R. Siegwolf (eds), Isotopes as tracers of ecological change. Elsevier Academic Press. (in review).

 

Refereed journal articles

 

Williams, D.G. and D.D. Briske. 1991. Size and ecological significance of the physiological individual in the bunchgrass Schizachyrium scoparium. Oikos 62:41-47.

Williams, D.G. and R.A. Black. 1993. Phenotypic variation in contrasting temperature environments: Growth and photosynthesis in Pennisetum setaceum from different altitudes on Hawaii. Functional Ecology 7:623-633.

Williams, D.G. and R.A. Black. 1994. Response to drought for a native and introduced Hawaiian grass. Oecologia 97:512-519.

Williams, D.G., Mack, R.N. and R.A. Black. 1995. Ecophysiology and growth of introduced Pennisetum setaceum on Hawaii: The role of phenotypic plasticity. Ecology 76:1569-1580.

Williams, D.G. and R.A. Black. 1996. Resource limitations to growth and gas exchange for introduced Pennisetum setaceum on Hawaii. Canadian Journal of Botany 74:268-265.

Williams, D.G. and J.R. Ehleringer. 1996. Carbon isotope discrimination in three semi-arid woodland species along a monsoon gradient. Oecologia 106:455-460.

Linton, M.J., J.S. Sperry, and D.G. Williams. 1998. Xylem cavitation in roots and branches of Juniperus osteosperma and Pinus edulis. Functional Ecology 12:906-911.

Williams, D.G. and J. R. Ehleringer. 2000. Carbon isotope discrimination and water relations of oak hybrid populations in southwestern Utah. Western North American Naturalist 60:121-129.

Cooper, D.I., W.E. Eichinger, L. Hipps, J. Kao, J. Reisner, S. Smith, *S.M. Schaeffer, and D.G. Williams. 2000. Spatial and temporal properties of water vapor and flux over a riparian canopy. Agricultural and Forest Meteorology 105:161-183.

Goodrich, D.C., A. Chehbouni, B. Goff, B. MacNish, T. Maddock, S. Moran, W.J. Shuttleworth, D.G. Williams et al. 2000. Preface paper to the Semi-Arid Land-Surface-Atmosphere (SALSA) program special issue. Agricultural and Forest Meteorology 105:3-19.

Goodrich, D.C., R. Scott, J. Qi, B. Goff, C.L. Unkrich, M.S. Moran, D.G. Williams, *S. Schaeffer, *K. Snyder, R. MacNish, T. Maddock, D. Pool, A. Chehbouni, D.I. Cooper, W.E. Eichinger, W.J. Shuttleworth, Y. Kerr, R. Marsett, and W. Ni. 2000. Seasonal estimates of riparian evapotranspiration using remote and in-situ measurements.  Agricultural and Forest Meteorology 105:281-309.

*Schaeffer, S.M., D.G. Williams, and D.C. Goodrich. 2000. Transpiration in cottonwood/willow forest patches estimated from sap flux. Agricultural and Forest Meteorology 105:257-270.

*Snyder, K. and D.G. Williams. 2000. Water sources used by riparian trees varies among stream types on the San Pedro river, Arizona. Agricultural and Forest Meteorology 105:227-240.

Williams, D.G. and J. R. Ehleringer. 2000. Intra- and interspecific variation for summer precipitation use in pinyon-juniper woodlands. Ecological Monographs 70:517-537.

Williams, D.G. and Z. Baruch. 2000. African grass invasion in the Americas: ecosystem consequences and the role of ecophysiology. Biological Invasions. 2:123-140.

Wall, G.W., T.J. Brooks, N.R. Adam, A. Cousins, B.A. Kimball, P.J. Pinter, Jr, R.L. LaMorte, J. Triggs, M.J. Ottman, S.W. Leavitt, A.D. Matthias, D.G. Williams, and A.N. Webber. 2001. Elevated atmospheric CO2 improved sorghum plant water status by ameliorating the adverse effects of drought. New Phytologist 152:231-248.

Weltzin, J.F., *K.A. Snyder, and D.G. Williams. 2001. Changes in precipitation seasonality and oak (Quercus) recruitment: linking physiology and demography. Western North American Naturalist 61:463-472.

Williams, D.G., *V. Gempko, *A. Fravolini, S.W. Leavitt, G.W. Wall, B.A. Kimball, P.J. Pinter Jr., R. LaMorte, and M. Ottman. 2001. Carbon isotope discrimination by Sorghum bicolor under CO2 enrichment and drought. New Phytologist 150:285-293.

*Fravolini, A., D.G. Williams, and T.L. Thompson. 2002. Carbon isotope discrimination and bundle sheath leakiness in three C4 subtypes grown under variable nitrogen, water and atmospheric CO2 supply. Journal of Experimental Botany 53:2261-2269.

Brooks, J.R., N. Buchmann, S. Phillips, B. Ehleringer, R. Evans, L.A. Martinelli, W.T. Pockman, D. Sandquist, J.P. Sparks, L. Sperry, D.G. Williams, and J.R. Ehleringer. 2002. Heavy and light beer: a carbon isotope approach to detecting C4 carbon in beers of different origins, styles and prices. Journal of Agricultural & Food Chemistry 50:6413-6418.

Scott, R.L., C. Watts, J. Garatuza, E. Edwards, D.C. Goodrich, D.G. Williams, and W.J. Shuttleworth. 2003. The understory and overstory partitioning of energy and water fluxes in a semi-arid woodland ecosystem. Agricultural and Forest Meteorology 114:127-139.

*Hultine, K.L., *W.L. Cable, S.S.O. Burgess, and D.G. Williams. 2003. Hydraulic redistribution by deep roots of a Chihuahuan desert phreatophyte. Tree Physiology 23:353-360.

*Hultine, K., D.G. Williams, S.S.O. Burgess, and T.O. Keefer. 2003. Hydraulic redistribution and diurnal storage capacitance in desert phreatophytes. Oecologia 135:167-175.

*Snyder, K.A., and D.G. Williams. 2003. Experimental defoliation differentially alters water uptake by deep and shallow roots of Prosopis velutina (velvet mesquite). Functional Ecology 17:363-374.

*Yepez, E.A., D.G. Williams, R. Scott, and G. Lin. 2003. Partitioning overstory and understory evapotranspiration in a semi-arid savanna ecosystem from the isotopic composition of water vapor. Agricultural and Forest Meteorology 119:53-68.

Weltzin, J.F., M.E. Loik, S. Schwinning, D.G. Williams, P. Fay, B. Haddad, J. Harte, T.E. Huxman, A.K. Knapp, G. Lin, W.T. Pockman, M.R. Shaw, E. Small, M.D. Smith, S.D. Smith, D.T. Tissue, and J.C. Zak. 2003. Assessing the response of terrestrial ecosystems to potential changes in precipitation. BioScience 53:941-952.

*Potts, D.L. and D.G. Williams. 2004. Response of tree ring Holocellulose d13C to moisture availability in Populus fremontii at perennial and intermittent stream reaches. Western North American Naturalist 64:27-37.

Huxman T.E., M.D. Smith, P.A. Fay, A.K. Knapp, M.R. Shaw, M.E. Loik, S.D. Smith, D.T. Tissue, J.C. Zak, J.F. Weltzin, W.T. Pockman, O.E. Sala, B. Haddad, J. Harte, G.W. Koch, S. Schwinning, E.E. Small, and D.G. Williams. 2004. Precipitation and production: convergence across biomes to a common rain-use efficiency. Nature 429:651-654.

Guerenstein, P.G., *E.A. Yepez, J. van Haren, D.G. Williams, J.G. Hildebrand. 2004. Floral CO2 emission may indicate food abundance to nectar-feeding moths. Naturwissenschaften 91:329-333.

*Hultine, K.R., R.L. Scott, *W.L. Cable, and D.G. Williams. 2004. Hydraulic redistribution by a dominant, warm-desert phreatophyte: seasonal patterns and response to precipitation pulses. Functional Ecology 18:530-538.

Williams, D.G., *W. Cable, *K. Hultine, J.C.B. Hoedjes, *E. Yepez, V. Simonneaux, S. Er-Raki, G. Boulet, H.A.R. de Bruin, A. Chehbouni, O.K. Hartogensis and F. Timouk. 2004. Components of evapotranspiration determined by stable isotope, sap flow and eddy covariance techniques. Agricultural and Forest Meteorology 125:241-258.

Huxman, T.E., J.M. Cable, D.D. Ignace, J.A. Eilts, *N.B. English, J. Weltzin, and D.G. Williams. 2004. Response of net ecosystem gas exchange to a simulated precipitation pulse in a semi-arid grassland: the role of native and non-native grasses and soil texture. Oecologia 141:295-305.

*Salo, L.F., G.R. McPherson, and D.G. Williams. 2005. Sonoran Desert winter annuals affected by density of red brome and soil nitrogen. The American Midland Naturalist 153:95-109.

*English, N.B, J.F. Weltzin, *A. Fravolini, L. Thomas, D.G. Williams. 2005. The influence of soil texture and vegetation on soil moisture under rainout shelters in a semi-desert grassland. Journal of Arid Environments 63:324-343.

Williams, D.G., J. Coltrain, M. Lott, *N. English, and J.R. Ehleringer. 2005. Oxygen isotopes in cellulose identify source water for archeological maize in the American Southwest. Journal of Archaeological Science 32:931-939.

*Fravolini, A., *K. Hultine, E. Brugnoli, *R. Gazal, *N. English and D.G. Williams. 2005. Precipitation pulse use by an invasive woody legume: the role of soil texture and pulse size. Oecologia 144:618-627.

Pendall, E., D.G. Williams and S.W. Leavitt. 2005. Seasonal and diurnal variations in pinon pine leaf water isotopic enrichment across a summer moisture gradient. Oecologia 145:605-618.

Ferrio, J.P., V. Resco, D.G. Williams, L. Serrano, J. Voltas. 2005. Stable isotopes in arid and semi-arid forest systems.  Investigaci—n Agraria. Sistemas y Recursos Forestales Monogr‡fico, 1-12.

Potts, D.L., T.E. Huxman, B.J. Enquist, J. Weltzin and D.G. Williams. 2005. Resilience and resistance of ecosystem functional response to a precipitation pulse in a semi-arid grassland. Journal of Ecology 94:23-30.

*Yepez, E.A., T.E. Huxman, D.D. Ignace, *N.B. English, J.F. Weltzin, A.E. Castellanos and D.G. Williams. 2005. Dynamics of transpiration and evaporation following a moisture pulse in semiarid grassland: a chamber-based isotope method for partitioning flux components. Agricultural and Forest Meteorology 132:359-376.

*Hultine K.R., *D.F. Koepke, W.T. Pockman , *A. Fravolini, J.S. Sperry and D.G. Williams. 2006. Influence of soil texture on hydraulic properties and water relations of a dominant warm-desert Phreatophyte. Tree Physiology 26:313-323.

Scott, R.L., T.E. Huxman, D.G. Williams, D.C. Goodrich. 2006. Ecohydrological impacts of woody plant encroachment: seasonal patterns of water and carbon dioxide exchange within a semiarid riparian environment. Global Change Biology 12:311Ð324.

*Gazal, R., R.L. Scott, D.C. Goodrich and D.G. Williams. 2006. Controls on transpiration in a desert riparian cottonwood forest. Agricultural and Forest Meteorology 137:56Ð67.

Potts, D.L., T.E. Huxman, J.M. Cable, N.B. English, D.D. Ignace, J.A. Eilts, M.J. Mason, J.F. Weltzin and D.G. Williams. 2006. Antecedent moisture and seasonal precipitation influence response of canopy-scale carbon and water exchange to rainfall pulses in semi-arid grassland. New Phytologist doi:10.1111/j.1469-8137.2006.01732.x.

Williams, D.G., T.E. Huxman, R.L. Scott, D. Goodrich and G. Lin. 2006. Sensitivity of riparian ecosystems in arid and semiarid environments to moisture pulses. Hydrological Processes (in press).

Potts, D.L., R.L. Scott, D.G. Williams, D.C. Goodrich and T.E. Huxman. The sensitivity of ecosystem carbon exchange to seasonal precipitation and woody plant encroachment. Oecologia (in press).

 

Other articles

 

Hipps, L. E., D. Cooper, W. Eichinger, D. Williams, et al. 1998. A summary of processes which are connected to evaporation of riparian and heterogeneous upland vegetation in arid regions. Pages 13-17, In Wood, E.F., Chehbouni, A.G., Goodrich, D.C., Seo, D.J., Zimmerman, J.R., eds., Proceedings from the special symposium on hydrology: Boston, Mass., American Meteorological Society, Boston, Massachusetts.

Maddock III, T., R.D. MacNish, D.C. Goodrich, D.G. Williams, W.J. Shuttleworth, et al. 1998. The overview of atmospheric and surface water coupling to regional groundwater models in semi-arid basins. Pages 38-42, In Wood, E.F., A.G. Chehbouni, D.C. Goodrich, D.J. Seo, and J.R. Zimmerman, technical coordinators. Proceedings from the Special Symposium on Hydrology. American Meteorological Society, Boston, Massachusetts.

Moran, S., D. Williams, D. Goodrich, A. Chehbouni et al. 1998. Overview of remote sensing of semi-arid ecosystem function in the upper San Pedro river basin. Pages 49-54, In Wood, E.F., A.G. Chehbouni, D.C. Goodrich, D.J. Seo, and J.R. Zimmerman, technical coordinators. Proceedings from the Special Symposium on Hydrology. American Meteorological Society, Boston, Massachusetts.

Qi, J., M.S. Moran, D.C. Goodrich, R. Marsett, R. Scott, A. Chehbouni, S. Schaeffer, J. Schieldge, D. Williams, T. Keefer, D. Cooper, L. Hipps, W. Eichinger, and W. Ni. 1998. Estimation of evapotranspiration over the San Pedro riparian area with remote and in situ measurements. Pages 55-60, In Wood, E.F., A.G. Chehbouni, D.C. Goodrich, D.J. Seo, and J.R. Zimmerman, technical coordinators. Proceedings from the Special Symposium on Hydrology. American Meteorological Society, Boston, Massachusetts.

*Schaeffer, S., and D.G. Williams. 1998. Transpiration of desert riparian forest canopies estimated from sap flux. Pages 180-184, In Wood, E.F., A.G. Chehbouni, D.C. Goodrich, D.J. Seo, and J.R. Zimmerman, technical coordinators. Proceedings from the Special Symposium on Hydrology. American Meteorological Society, Boston, Massachusetts.

*Snyder, K.A., D.G. Williams, and V.L. Gempko. 1998. Water source determination for cottonwood, willow and mesquite in riparian forest stands. Pages 185-188, In Wood, E.F., A.G. Chehbouni, D.C. Goodrich, D.J. Seo, and J.R. Zimmerman, technical coordinators. Proceedings from the Special Symposium on Hydrology. American Meteorological Society, Boston, Massachusetts.

Williams, D.G., J.-P. Brunel, S.M. Schaeffer, and K.A. Snyder. 1998. Biotic controls over the functioning of desert riparian ecosystems. Pages 43-48, In Wood, E.F., A.G. Chehbouni, D.C. Goodrich, D.J. Seo, and J.R. Zimmerman, technical coordinators. Proceedings from the Special Symposium on Hydrology. American Meteorological Society, Boston, Massachusetts.

Williams, D.G. 1999. The roots of grass success. BioScience 49:667-670. Book review of Population biology of grasses by G.P. Cheplick (ed.).

Matthias, A.D., S.W. Leavitt, T.L. Thompson, B.A. Kimball, P.J. Pinter Jr, G.W. Wall, R.S. Rauschkolb, M.J. Ottman, R.L. Roth, T.J. Brooks, N.R. Adam, R.L. LaMorte, G. Weschsung, F. Weschung, F.J. Adamsen, D.G. Williams, F.S. Nakayama, D.J. Hunsacker, J. Watson, S.A. White, J.T. Welzmiller. 2001. Free-air CO2 enrichment effects on wheat and sorghum at Maricopa, Arizona, USA. In Carbon dioxide and vegetation: advanced international approaches for absorption of CO2 and responses to CO2 -The 13th Global Environment Tsukuba-, CGER-I046-2001, CGER/NIES.

*Fravolini, A., K.R. Hultine, D.F. Koepke, and D.G. Williams. 2003. The role of soil texture on mesquite water relations and response to summer precipitation. In: Santa Rita Experimental Range: One Hundred Years (1903 to 2003) of accomplishments and contributions; conference proceedings; 2003 October 30 - November 1, Tucson, AZ. Proc. RMRS-P-00. Ogden, UT: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station.

*English, N.B., D.G. Williams, and J.F. Weltzin. 2003. Dynamics of soil temperature and moisture following experimental irrigation on the Santa Rita Experimental Range. In: Santa Rita Experimental Range: One Hundred Years (1903 to 2003) of accomplishments and contributions; conference proceedings; 2003 October 30 - November 1, Tucson, AZ. Proc. RMRS-P-00. Ogden, UT: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station.

Weltzin, J.F. and D.G. Williams. 2003. Isotopes for Ecosystems. Editorial on ÒTracing changes in ecosystem function under elevated CO2Ó by Pataki et al. BioScience 53:795.

Goodrich, D.C., D.G. Williams, C.L. Unkrich, R.L. Scott, *K.R. Hultine, D. Pool, A. Coes, and J. Hogan. 2003. Ephemeral channel recharge and evapotranspiration from near-channel vegetation. Proceedings of Research in the Watersheds Conference. 50th anniversary of Walnut Gulch, USDA-ARS.

Williams, D.G. 2005. Isotopes reveal sources and sinks of trace gases. Book review of Stable isotopes and biosphere-atmosphere interactions by Larry Flanagan, Jim Ehleringer and Diane Pataki (eds). Ecology 86:3131-3132.

Williams, D.G. 2005. Book review of Ecohydrology of water-controlled ecosystems: soil moisture and plant dynamics by Ignacio Rodr’guez-Iturbe and Amilcare Porporato. Eos, Transactions of the American Geophysical Union 86:344.

Scott, R.L., D. Williams, D. Goodrich, W. Cable, L. Levick, R. McGuire, R. Gazal, E. Yepez, P. Ellsworth and T. Huxman. 2006. Determining the riparian groundwater use within the San Pedro Riparian National Conservation Area and the Sierra Vista Sub-Basin, Arizona. In Hydrologic Requirements of and Consumptive Ground-Water Use by Riparian Vegetation along the San Pedro River, Arizona. Compiled by J.M. Leenhouts, J.C. Stromberg, and R.L. Scott. U.S. Geological Survey Scientific Investigations Report.

 

Significant reports

 

Scott, R.L., D.C. Goodrich, L. Levick, R. McGuire, W. Cable, D.G. Williams, R. Gazal, E. Yepez, P Ellsworth and T. Huxman. 2004. San Pedro Riparian National Conservation Area (SPRNCA) water needs study:A research effort funded by the Upper San Pedro Partnership. 79 pp.

Williams, D.G., D. Evans and J. Ehleringer. 2005. On developing a plan for an isotope network within NEON: Report from two BASIN workshops. 30 pp.

 

Presentations

 

Invited seminar and symposium presentations

 

Williams, D.G. 1992. Plasticity of growth and photosynthesis in populations of Fountaingrass (Pennisetum setaceum) from different elevations on Hawaii. Department of Botany, University of Hawaii at Manoa.

Williams, D.G. 1994. Use of summer precipitation in pinyon-juniper woodlands along a summer precipitation gradient. School of Forestry, Northern Arizona University, Flagstaff.

Williams, D.G. 1996. Water use by desert plants: monsoons, drought, and response to change.  Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ.

Williams, D.G. and J.R. Ehleringer. 1996. Use of monsoon precipitation by semi-arid woodland species along a monsoon gradient. American Association for the Advancement of Science, Southwestern Region Annual Meeting, Flagstaff, Arizona.

Ehleringer, J.R., R.D. Evans and D.G. Williams. 1996. Sensitivity to change in aridland ecosystems. Symposium: Stable isotopes and the integration of biological, ecological and geochemical processes. Newcastle, UK.

Williams, D.G. 1996. Water use by desert plants: monsoons, drought, and response to change.  Department of Biology, University of Arkansas, Fayetteville, AR.

Williams, D.G. 1997. Plant functional attributes in southwestern savannas: Can we generalize? Symposium: Natural and anthropogenic influences on savanna ecosystems of the arid southwest. Ecological Society of America Annual Meeting, Albuquerque, New Mexico.

Williams, D.G. 1997. Water use by desert plants: monsoons, drought, and response to change. Universidad de Sonora, Hermasillo, Mexico.

Williams, D.G. 1997. Water use by desert plants: monsoons, drought, and response to change.  Department of Biology, Boise State University, Boise, ID.

Williams, D.G., D.R. Sandquist, and Z. Baruch. 1998. Ecophysiological processes related to invasion and ecosystem dominance by African C4 grasses. Symposium: Biotic invasions: a global perspective. VII International Congress of Ecology, Florence, Italy.

Williams, D.G. 1998. Sources of water used by desert riparian trees: The root causes. Department of Plant Sciences, University of Arizona, Tucson, AZ.

Williams, D.G. 1999. Regulation of the hydrologic cycle by plants: The root causes.  Department of Plant Biology, Arizona State University, Tempe, AZ.

Williams, D.G. 2000. Root system dynamics and resource patchiness in semi-arid ecosystems. Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN.

Williams, D.G. 2002. Precipitation pulse use by plants in arid and semiarid environments: an isotopic perspective. Department of Renewable Resources, University of Wyoming, Laramie, WY.

Hultine, K.R., W.L. Cable, D.G. Williams, P.Z. Ellsworth, and R.L. Scott. 2002. Transpiration by mesquite on a desert river floodplain. The American Geophysical Union Chapman Conference on Eco-Hydrology of Semiarid Landscapes: Interactions and Processes, Taos, NM.

Williams, D.G. 2002. Precipitation pulse use by plants in arid and semiarid environments. Centre dÕEtudes Spatiales de la Biosphere, Centre National de la Recherche Scientifique, Toulouse, France.

Williams, D.G. 2003. Resource pulses in arid and semiarid environments: responses from leaf to catchment scales. Natural Resources Ecology Laboratory, Colorado State University, Ft. Collins, CO.

Williams, D.G. 2004. Plant ecology meets hydrology - examples from the arid Southwest. Department of Integrative Biology, The University of Texas, Austin, TX.

Williams, D.G. and E.A. Yepez. 2004. Tracing sources of evapotranspiration using stable isotopes: challenges and new opportunities. Invited symposium presentation; Eco-hydrology. Ecological Society of America annual meeting, August 3, 2004, Portland, OR.

Williams, D.G. 2004. Eco-hydrology and hydro-ecology: a synthetic view of vegetation-water interactions in arid regions. School of Biological Sciences, Washington State University, Pullman, WA.

Williams, D.G., R.L. Scott, T.E. Huxman and D.C. Goodrich. 2005. Multi-scale eco-hydrology of riparian ecosystems in the desert Southwest. Invited symposium presentation; Ecohydrology: emerging issues. Society for Range Management annual meeting, February 7, 2005, Fort Worth, TX.

Williams, D.G. 2005. The use of stable isotopes to investigate dynamics of dryland communities and ecosystems. Invited symposium presentation; The biology of dryland plants. Botanical Society of America annual meeting, August 17, 2005, Austin, TX.

Williams, D.G. 2005. Ph