Publications

Posters and Talks - Reports

Journal Articles

  • Bhatt, U.S., Walker, D.A., Raynolds, M.K., Comiso, J.C., Epstein, H.E., Jia, G.J., Gens, R., Pinzon, J.E., Tucker, C.J., Tweedie, C.E., Webber, P.J. 2010. Circumpolar Arctic tundra vegetation change is linked to sea-ice decline. Earth Interactions. 14:(8):1-20. PDF
  • Bigelow, N.H., Brubaker, L.B., Edwards, M.E., Harrison, S.E., Prentice, I.C., Anderson, P.M., Andreev, A.A., Bartlein, P.J., Christensen, T.R., Cramer, W., Kaplan, J.O., Lozhkin, A.V., Matveyeva, N.V., Murray, D.F., McGuire, A.D., Razzhivin, Y.Y., Ritchie, J.C., Smith, B., Walker, D.A., Gajewski, K., Wolf, V., Holmqvist, B.H., Igarashi, Y., Kremenetskii, K.V., Paus, A., Pisaric, M.F.J., Volkova, V.S. 2003. Climate change and Arctic ecosystems I: Vegetation changes north of 55° N between the last glacial maximum, mid-Holocene and present. Journal of Geophysical Research. 108(D19). PDF. doi:10.1029/2002JD002558.
  • Bockheim, J.G., D.A. Walker and Everett, L.R. 1997. Soil carbon distribution in nonacidic and acidic tundra of Arctic Alaska. R. Lal, J.M. Kimble, R.F. Follett, B.A. Stewart (eds.) Soil processes and the carbon cycle (pp. 143-155). CRC Press: Boca Raton, FL. PDF
  • Bockheim, J.G., Walker, D.A., Everett, L.R., Nelson, F.E. and Shiklomanov, N.I. 1998. Soils and cryoturbation in moist nonacidic and acidic tundra in the Kuparuk river basin, arctic Alaska, USA. Arctic and Alpine Research. 30:(2):166-174. PDF
  • Chapin, F.S.I., Sturm, M., Serreze, M.C., McFadden, J.P., Key, J.R., Lloyd, A.H., McGuire, A.D., Rupp, T.S., Lynch, A.H., Schimel, J.P., Beringer, J., Chapman, W.L., Epstein, H.E., Euskirchen, E.S., Hinzman, L.D., Jia, G., Ping, C.-L., Tape, K.D., Thompson, C.D.C., Walker, D.A., Welker, J.M. 2005. Role of land-surface changes in Arctic summer warming. Science. 310:(5748):657-660. PDF
  • Daanen, R., Misra, D., Epstein, H.E. 2007. Active-layer hydrology in nonsorted circle ecosystems of the arctic tundra. Vadose Zone Journal. 6(4):694-704.
  • Daniëls, F.J., Bültmann, H., Lünterbusch, C., Wilhelm, M. 2000. Vegetation zones and biodiversity of the North-American Arctic. Berichte der Reinhold-Tüxen-Gesellschaft. 12:131-151.
  • Elvebakk, A. 1997. Tundra diversity and ecological characteristics of Svalbard. Wielgolaski, F.E. (eds.) Polar and Alpine Tundra. Elsevier. Amsterdam. pp. 347-399.
  • Elvebakk, A., Elven, R., Razzhivin, V.Y. 1999. Delimitation, zonal and sectorial subdivision of the Arctic for the Panarctic Flora Project. Nordal, I., Razzhivin, V.Y. (eds.) The Species Concept in the High North - A Panarctic Flora Initiative. The Norwegian Academy of Science and Letters. Oslo. pp. 375-386. PDF
  • Epstein, H.E., Beringer, J., Copass, C., Gould, W., Lloyd, A., Chapin III, F.S., Ping, C.L., Michaelson, G., Rupp, S., Walker, D.A. 2004. The nature of spatial transitions in arctic ecosytems. Journal of Biogeography. 31:1917-1933. PDF. doi:10.1111/j.1365-2699.2004.01140.x.
  • Epstein, H.E., Raynolds, M.K., Walker, D.A., Bhatt, U.S., Tucker, C.J., Pinzon, J.E. 2012. Dynamics of aboveground phytomass of the circumpolar arctic tundra during the past three decades. Environmental Research Letters. 7(1):12. PDF. doi:10.1088/1748-9326/7/1/015506.
  • Epstein, H.E., Walker, D.A., Raynolds, M.K., Jia, G.J., Kelley, A.M. 2008. Phytomass patterns across a temperature gradient of the North American arctic tundra. Journal of Geophysical Research - Biogeosciences. 113:1-11. PDF
  • Epstein, H.E., Yu, Q., Kaplan, J.O., Lischke, H. 2007. Simulating future changes in arctic and subarctic vegetation. Computing in Science and Engineering. 9(4):12-23. PDF. doi:10.1109/MCSE.2007.84.
  • Evans, B.M., Walker, D.A., Benson, C.S., Nordstrand, E.A., Petersen, G.W. 1989. Spatial interrelationships between terrain, snow distribution and vegetation patterns at an arctic foothills site in Alaska. Holarctic Ecology. 12:270-278. PDF
  • Goetz, S.J., Epstein, H.E., Alcaraz, J.D., Beck, P.S.A., Bhatt, U.S., Bunn, A., Comiso, J.C., Jia, G.J., Kaplan, J.O., Lilschke, H., Lloyd, A., Walker, D.A., Yu, Q. 2011. Recent changes in Arctic vegetation: Satellite observations and simulation model predictions. G. Gutman and A. Reissell (eds.). Eurasian Arctic Land Cover and Land Use in a Changing Climate (pp. 9-36). Springer: New York, NY. PDF
  • Gould, W.A., Edlund, S., Zoltai, S., Raynolds, M.K., Walker, D.A., Maier, H.A. 2002. Canadian Arctic vegetation mapping. International Journal of Remote Sensing. 23(21):4597-4609. PDF. doi:10.1080/01431160110113962.
  • Gould, W.A., Raynolds, M.A., Walker, D.A. 2003. Vegetation, plant biomass, and net primary productivity patterns in the Canadian Arctic. Journal of Geophysical Research. 108(D2):1-14. PDF. doi:10.1029/2001JD000948.
  • Gould, W.A., Walker, D.A., Biesboer, D. 2003. Combining research and education: Bioclimatic Zonation along a Canadian Arctic Transect. Arctic. 56:(1):45-54. PDF
  • Hinzman, L.D., Bettez, N.D., Bolton, W.R., Chapin, F.S., III, Dyurgerov, M.B., Fastie, C.L., Griffith, B., Hollister, R.D., Hope, A., Huntington, H.P., Jensen, A., Jia, G.J., Jorgenson, T., Kane, D.L., Klein, D.R., Kofinas, G., Lynch, A.H., Lloyd, A.H., McGuire, A.D., Nelson, F., Oechel, W.C., Osterkamp, T.E., Racine, H.C., Romanovsky, V.E., Stone, R., Stow, D.A., Sturm, M., Tweedie, C.E., Vourlitis, G.L., Walker, M.D., Walker, D.A., Webber, P.J., Welker, J.M., Winker, K.S., Yoshikawa, K. 2005. Evidence and implications of recent climate change in northern Alaska and other Arctic regions. Climatic Change. 72:251-298. PDF. doi:10.1007/s10584-005-5352-2.
  • Jia, G.J., Epstein, H.E., Walker, D.A. 2009. Vegetation greening in the Canadian Arctic related to decadal warming. Journal of Environmental Monitoring. 11:2231-2238. . doi:10.1039/B911677J.
  • Jia, G.J., Epstein, H.E., Walker, D.A. 2004. Controls over intra-seasonal dynamics of AVHRR NDVI for the Arctic tundra in northern Alaska. International Journal of Remote Sensing. 25(9):1547-1564. PDF. doi:10.1080/0143116021000023925.
  • Jia, G.J., Epstein, H.E., Walker, D.A. 2002. Spatial characteristics of AVHRR-NDVI along latitudinal transects in northern Alaska. Journal of Vegetation Science. 13:(3):315-326. PDF
  • Kade, A., Romanovsky, V.E., Walker, D.A. 2006. The N-factor of nonsorted circles along a climate gradient in Arctic Alaska. Permafrost and Periglacial Processes. 17(4):279-289. PDF. doi:10.1002/ppp.563.
  • Kade, A., Walker, D.A., Raynolds, M.K. 2005. Plant communities and soils in cryoturbated tundra along a bioclimate gradient in the Low Arctic, Alaska. Phytocoenologia. 35:(4):761-820. PDF
  • Kaplan, J.O., Bigelow, N.H., Prentice, I.C., Harrison, S.P., Bartlein, P.J., Christensen, T.R., Cramer, W., Matveyeva, N.V., McGuire, A.D., Murray, D.F., Razzhivin, V.Y., Smith, B., Walker, D.A., Anderson, P.M., Andreev, A.A., Brubaker, L.B., Edwards, M.E., Lozhkin, L.V. 2003. Climate change and Arctic ecosystems II: Modeling, paleodata-model comparisons, and future projections. Journal of Geophysical Research. 108 (D19). PDF. doi:10.1029/2002JD002559.
  • Kataoka, M. 2009. ESRI Map Book, Volume 24. ESRI Press. Redlands, CA. 24(24). 120 . PDF - ESRI Map Book, Volume 24: Vegetation in the Vicinity of the Toolik Field Station, Alaska; Alaska Geobotany Center
  • Kelley, A.M., Epstein, H.E. 2009. Effects of nitrogen fertilization on plant communities of nonsorted circles in moist nonacidic tundra, Northern Alaska. Arctic, Antarctic, and Alpine Research. 41(1):119-127. PDF. doi:10.1657/1523-0430-41.1.119.
  • Kelley, A.M., Epstein, H.E., Ping, C.-L., Walker, D.A. 2012. Soil nitrogen transformations associated with small patterned-ground features along a North American Arctic transect. Permafrost and Periglacial Processes. 23:196-206. PDF. doi:10.1002/ppp.1748.
  • Michaelson, G.J., Ping, C.L., Epstein, H., Kimble, J.M., Walker, D.A. 2008. Soils and frost boil ecosystems across the North American Arctic Transect. Journal of Geophysical Research - Biogeosciences. 113:G03S11, 10.1029/2007JG000672. PDF. doi:10.1029/2007JG000672.
  • Muller, S.V., Racoviteanu, A.E., Walker, D.A. 1999. Landsat MSS-derived land-cover map of northern Alaska: extrapolation methods and a comparison with photo-interpreted and AVHRR-derived maps. International Journal of Remote Sensing. 20:2921-2946. PDF. doi:10.1080/014311699211543.
  • Muller, S.V., Walker, D.A., Nelson, F.E., Auerbach, N., Bockheim, J., Guyer, S. and Sherba, D. 1998. Accuracy assessment of a land-cover map of the Kuparuk River basin, Alaska: considerations for remote regions. Photogrammetric Engineering & Remote Sensing. 64:(6):619-628. PDF
  • Nelson, F.E., Hinkel, K.M., Shiklomanov, N.I., Mueller, G.R., Miller, L.L., Walker, D.A. 1998. Active-layer thickness in north central Alaska: Systematic sampling, scale, and spatial autocorrelation. Journal of Geophysical Research. 103:(D22):28963-28973. PDF
  • Nelson, F.E., Shiklomanov, N.I., Mueller, G.R., Hinkel, K.M., Walker, D.A. and Bockheim, J.G. 1997. Estimating active-layer thickness over a large region: Kuparuk River Basin, Alaska, USA. Arctic, Antarctic, and Alpine Research. 29:(4):367-378. PDF
  • Ping, C.-L., Bockheim, J.G., Kimble, J.M., Michaelson, G.J., Walker, D.A. 1998. Characteristics of cryogenic soils along a latitudinal transect in Arctic Alaska. Journal of Geophysical Research. 103:(D22):28917-28928. PDF
  • Ping, C.-L., Michaelson, G.J., Kimble, J.M., Walker, D.A. 2005. Soil acidity and exchange properties of cryogenic soils in Arctic Alaska. Journal of Soil Science and Plant Nutrition. 51(5):649-653. PDF. doi:10.1111/j.1747-0765.2005.tb00083.x.
  • Raynolds, M.K., Comiso, J.C., Walker, D.A., Verbyla, D. 2008. Relationship between satellite-derived land surface temperatures, arctic vegetation types, and NDVI. Remote Sensing of Environment. 112(4):1884-1894. PDF. doi:10.1016/j.rse.2007.09.008.
  • Raynolds, M.K., Walker, D.A. 2009. Effects of deglaciation on circumpolar distribution of arctic vegetation. Canadian Journal of Remote Sensing. 35:(2):118-129. PDF
  • Raynolds, M.K., Walker, D.A., Epstein, H.E., Pinzon, J.E., Tucker, C.J. 2012. A new estimate of tundra-biome phytomass from trans-Arctic field data and AVHRR NDVI. Remote Sensing Letters. 3:403-411. PDF. doi:10.1080/01431161.2011.609188.
  • Raynolds, M.K., Walker, D.A., Maier, H.A. 2006. NDVI patterns and phytomass distribution in the circumpolar Arctic. Remote Sensing of Environment. 102:271-281. PDF. doi:10.1016/j.rse.2006.02.016.
  • Raynolds, M.K., Walker, D.A., Maier, H.A. 2005. Plant community-level mapping of arctic Alaska based on the Circumpolar Arctic Vegetation Map. Phytocoenologia. 35(4):821-848. PDF. doi:10.1127/0340-269X/2005/0035-0821.
  • Raynolds, M.K., Walker, D.A., Munger, C.A., Vonlanthen, C.M., Kade, A.N. 2008. A map analysis of patterned-ground along a North American Arctic Transect. Journal of Geophysical Research - Biogeosciences. 113:1-18. PDF. doi:10.1029/2007JG000512.
  • Reeburgh, W.S., King, J.Y., Regli, S.K., Kling, G.W., Auerbach, N.A., Walker, D.A. 1998. A CH4 emission estimate for the Kuparuk River basin, Alaska. Journal of Geophysical Research. 103(D22):29,005-29,013. PDF. doi:10.1029/98JD00993.
  • Riedel, S.M., Epstein, H.E., Walker, D.A. 2005. Biotic controls over spectral reflectance of arctic tundra vegetation. International Journal of Remote Sensing. 26(11):2391-2405. PDF. doi:10.1080/01431160512331337754.
  • Riedel, S.M., Epstein, H.E., Walker, D.A., Richardson, D.L., Calef, M.P., Edwards, E., Moody, A. 2005. Spatial and temporal heterogeneity of vegetation properties among four tundra plant communities at Ivotuk, Alaska, USA. Arctic, Antarctic, and Alpine Research. 37(1):25-33. PDF. doi:10.1657/1523-0430(2005)037[0025:SATHOV]2.0.CO;2.
  • Sappington, N. 2005. ESRI Map Book, Volume 20. ESRI Press. Redlands, CA. 20 (20). 120 . PDF - ESRI Map Book, Volume 20: Circumpolar Arctic Vegetation
  • Shippert, M.M., D.A. Walker, N.A. Auerbach, B.E. Lewis 1994. Regional biomass and leaf-area estimates derived from satellite imagery as inputs to spatial trace-gas models for arctic tundra. Annual Ecological Society of America (ESA) Meeting: science and public policy. 75:(2):211.
  • Shippert, M.M., Walker, D.A., Auerbach, N.A., Lewis, B.E. 1995. Biomass and leaf-area index maps derived from SPOT images for Toolik Lake and Imnavait Creek areas, Alaska. Polar Record. 31(177):147-154. PDF. doi:10.1017/S0032247400013644.
  • Stow, D., Hope, A., Boynton, W., Phinn, S., Walker, D., Auerbach, N. 1998. Satellite-derived vegetation index and cover type maps for estimating carbon dioxide flux for Arctic tundra regions. Geomorphology. 21:313-327. PDF. doi:10.1016/S0169-555X(97)00071-8.
  • Stow, D.A., Hope, A., D., M., Verbyla, D., Gamon, J., Huemmrich, F., Houston, S., Racine, C., Sturm, M., Tape, K., Hinzman, L., Yoshikawa, K., Tweedie, C., Noyle, B., Silapaswan, C., Douglas, D., Griffith, B., Jia, G., Epstein, H., Walker, D., Daeschner, S., Petersen, A., Zhou, L., Myneni, R. 2004. Remote sensing of vegetation and land-cover change in arctic tundra ecosystems. Remote Sensing of Environment. 89:281-308. PDF. doi:10.1016/j.rse.2003.10.018.
  • Vonlanthen, C.M., Walker, D.A., Raynolds, M.K., Kade, A., Kuss, H.P., Daniëls, F.J.A., Matveyeva, N.V. 2008. Patterned-ground plant communities along a bioclimate gradient in the High Arctic, Canada. Phytocoenologia. 38:23-63. PDF. doi:10.1127/0340-269X/2008/0038-0023.
  • Walker, D.A. 2007. The Circumpolar Arctic Vegetation Map, the Alaska Arctic Tundra Vegetation Map, and the Arctic Geobotanical Atlas. Proceedings of the Fourth International CAFF Flora Group Workshop. 15:60-62. PDF
  • Walker, D.A. 2000. Hierarchical subdivision of arctic tundra based on vegetation response to climate, parent material, and topography. Global Change Biology. 6(S1):19-34. PDF. doi:10.1046/j.1365-2486.2000.06010.x.
  • Walker, D.A. 1999. An integrated vegetation mapping approach for northern Alaska (1:4 M scale). International Journal of Remote Sensing. 20(15-16):2895-2920. PDF. doi:10.1080/014311699211534.
  • Walker, D.A. 1995. Toward a new circumpolar arctic vegetation map: St. Petersburg workshop. Arctic and Alpine Research. 31:169-178.
  • Walker, D.A. 1994. Information: Toward a new arctic vegetation map: St. Petersburg workshop. Arctic and Alpine Research. 27:103-104. PDF
  • Walker, D.A. 1980. Haul road mapping. P.J. Webber (eds.) Vegetation mapping and response to disturbances in northern Alaska. U.S. Army Cold Regions Research and Engineering Laboratory. Hanover, NH. pp. 72.
  • Walker, D.A. and Walker, M.D. 1996. Terrain and vegetation of the Imnavait Creek Watershed. J.F. Reynolds, J.D. Tenhunen (eds.) Landscape Function: Implications for Ecosystem Disturbance, a Case Study in Arctic Tundra (pp. 73-108). Springer-Verlag: New York, NY. PDF
  • Walker, D.A., Auerbach, N.A., Bockheim, J.G., Chapin, F.S., III, Eugster, W., King, J.Y., McFadden, J.P., Michaelson, G.J., Nelson, F.E., Oechel, W.C., Ping, C.L., Reeburg, W.S., Regli, S., Shiklomanov, N.I., Vourlitis, G.L. 1998. Energy and trace-gas fluxes across a soil pH boundary in the Arctic. Nature. 394:469-472. PDF. doi:10.1038/28839.
  • Walker, D.A., Auerbach, N.A., Shippert, M.M. 1995. NDVI, biomass, and landscape evolution of glaciated terrain in northern Alaska. Polar Record. 31(177):169-178. PDF. doi:10.1017/S003224740001367X.
  • Walker, D.A., Bay, C., Daniels, F.J.A., Einarsson, E., Elvebakk, A., Johansen, B.E., Kapitsa, A., Kholod, S.S., Murray, D.F., Talbot, S.S., Yurtsev, B.A., Zoltai, S.C. 1995. Toward a new arctic vegetation map: a review of existing maps. Journal of Vegetation Science. 6(3):427-436. PDF. doi:10.2307/3236242.
  • Walker, D.A., Bhatt, U.S., Callaghan, T.V., Comiso, J.C., Epstein, H.E., Forbes, B.C., Gill, M., Gould, W.A., Henry, G.H.R., Jia, G.J., Kokelj, S.V., Lantz, T.C., Oberbauer, S.F., Pinzon, J.E., Raynolds, M.K., Shaver, G.R., Tucker, C.J., Tweedie, C.E., Webber, P.J. 2011. [The Arctic] Land: Vegetation [in "State of the Climate in 2010"]. Bulletin of the American Meteorological Society. 92:S150-S152. . doi:10.1175/1520-0477-92.6.S1.
  • Walker, D.A., Bhatt, U.S., Callaghan, T.V., Comiso, J.C., Epstein, H.E., Forbes, B.C., Gill, M., Gould, W.A., Henry, G.H.R., Jia, G.J., Kokelj, S.V., Lantz, T.C., Oberbauer, S.F., Pinzon, J.E., Raynolds, M.K., Shaver, G.R., Tucker, C.J., Tweedie, C.E., Webber, P.J. 2011. Vegetation. J. Richter-Menge, M.O. Jeffries and J.E. Overland (eds.) Arctic Report Card 2011. NOAA Arctic Research Program. PDF
  • Walker, D.A., Bhatt, U.S., Comiso, J.C., Epstein, H.E., Gould, W.A., Henry, G.H.R., Jia, G.J., Kokelj, S.V., Lantz, T.C., Mercado-Diaz, J.A., Pinzon, J.E., Raynolds, M.K., Shaver, G.R., Tucker, C.J., Tweedie, C.E., Webber, P.J. 2010. [The Arctic] Land: Vegetation [in "State of the Climate in 2009"]. Bulletin of the American Meteorological Society. 91(7):S115-S116. PDF. doi:10.1175/BAMS-91-7-StateoftheClimate.
  • Walker, D.A., Bhatt, U.S., Epstein, H.E., Bieniek, P.A., Comiso, J.C., Frost, G.V., Pinzon, J., Raynolds, M.K., Tucker, C.J. 2012. [The Arctic] Changing Arctic tundra vegetation biomass and greenness [in "State of the Climate in 2011"]. Bulletin of the American Meteorological Society. 93(7):S138-139. PDF. doi:10.1175/2012BAMSStateoftheClimate.1.
  • Walker, D.A., Bhatt, U.S., Raynolds, M.K., Comiso, J.C., Epstein, H.E., Jia, G.J. 2009. [The Arctic] Land: Vegetation [in "State of the Climate in 2008"]. Bulletin of the American Meteorological Society. 90(8):S104-S105. PDF. doi:10.1175/BAMS-90-8-StateoftheClimate.
  • Walker, D.A., Bhatt, U.S., Raynolds, M.K., Comiso, J.C., Epstein, H.E., Jia, G.J., Pinzon, J.E., Tucker, C.J. 2009. Vegetation. J. Richter-Menge, M.O. Jeffries and J.E. Overland (eds.) Arctic Report Card 2008. NOAA Arctic Research Program. PDF
  • Walker, D.A., Binnian, E., Evans, B.M., Lederer, N.D., Nordstrand, E., Webber, P.J. 1989. Terrain, vegetation and landscape evolution of the R4D research site, Brooks Range Foothills, Alaska. Holarctic Ecology. 12:(3):238-261. PDF
  • Walker, D.A., Bockheim, J.G., Chapin, F.S., III, Eugster, W., Nelson, F.E., Ping, C.L. 2001. Calcium-rich tundra, wildlife, and ''the Mammoth Steppe''. Quaternary Science Reviews. 20:149-163. PDF. doi:10.1016/S0277-3791(00)00126-8.
  • Walker, D.A., Elvebakk, A., Talbot, S.S., Daniels, F.J.A. 2005. The Second International Workshop on Circumpolar Vegetation Classification and Mapping: a tribute to Boris A. Yurtsev. Phytocoenologia. 35(4):715-725. PDF. doi:10.1127/0340-269X/2005/0035-0715.
  • Walker, D.A., Epstein, H.E., Gould, W.A., Kelley, A.M., Kade, A.N., Knudson, J.A., Krantz, W.B., Michaleson, G., Peterson, R.A., Ping, C.L., Raynolds, M.K., Romanovsky, V.E., Shur, Y.L. 2004. Frost-boil ecosystems: complex interactions between landforms, soils, vegetation, and climate. Permafrost and Periglacial Processes. 15(2):171-188. PDF. doi:10.1002/ppp.487.
  • Walker, D.A., Epstein, H.E., Jia, J.G., Balser, A.W., Copass, C., Edwards, E.J., Gould, W.A., Hollingsworth, J., Knudson, J., Maier, H.A., Moody, A., Raynolds, M.K. 2003. Phytomass, LAI, and NDVI in northern Alaska: Relationships to summer warmth, soil pH, plant functional types, and extrapolation to the circumpolar Arctic. Journal of Geophysical Research - Atmospheres. 108(d2):8169. PDF. doi:10.1029/2001JD000986.
  • Walker, D.A., Epstein, H.E., Raynolds, M.K., Kuss, P., Kopecky, M.A., Frost, G.V., Daniëls, F.J.A., Leibman, M.O., Moskalenko, N.G., Matyshak, G.V., Khitun, O.V., Khomutov, A.V., Forbes, B.C., Bhatt, U.S., Kade, A.N., Vonlanthen, C.M., Tichy, L. 2012. Environment, vegetation and greenness (NDVI) along the North America and Eurasia Arctic transects. Environmental Research Letters. 7(1). PDF. doi:10.1088/1748-9326/7/1/015504.
  • Walker, D.A., Epstein, H.E., Romanovsky, V.E., Ping, C.L., Michaelson, G.J., Daanen, R.P., Shur, Y., Peterson, R.A., Krantz, W.B., Raynolds, M.K., Gould, W.A., Gonzalez, G., Nicolsky, D.J., Vonlanthen, C.M., Kade, A.N., Kuss, P., Kelley, A.M., Munger, C.A., Tarnocai, C.T., Matveyeva, N.V., Daniëls, F.J.A. 2008. Arctic patterned-ground ecosystems: A synthesis of field studies and models along a North American Arctic Transect. Journal of Geophysical Research - Biogeosciences. 113:G03S01. PDF. doi:10.1029/2007JG000504.
  • Walker, D.A., Everett, K.R., Acevedo, W., Gaydos, L., Brown, J., Webber, P.J. 1982. Landsat assisted environmental mapping in the Arctic National Wildlife Refuge, Alaska. U.S. Fish and Wildlife Service (eds.) Draft environmental impact statement and draft regulations for the proposed oil and gas exploration within the coastal plain of the Arctic National Wildlife Refuge, Alaska. Department of the Interior. Washington, D.C. pp. 829-890 with 3 maps.
  • Walker, D.A., Everett, K.R., Webber, P.J. 1983. Chapter 2: Geobotany. D.M. Troy (eds.) Prudhoe Bay Unit-Eileen West End Environmental Studies Program, Summer 1982. LGL Research Associates, Inc. Fairbanks, AK. pp. 77.
  • Walker, D.A., Gould, W.A., Maier, H.A., Raynolds, M.K. 2002. The Circumpolar Arctic Vegetation Map: AVHRR-derived base maps, environmental controls, and integrated mapping procedures. International Journal of Remote Sensing. 23(21):4551-4570. PDF. doi:10.1080/01431160110113854.
  • Walker, D.A., Jia, G.J., Epstein, H.E., Raynolds, M.K., Chapin , F.S., III, Copass, C.D., Hinzman, L.D., Knudson, J.A., Maier, H.A., Michaelson, G.J., Nelson, F., Ping, C.L., Romanovsky, V.E., Shiklomanov, N. 2003. Vegetation-soil-thaw-depth relationships along a low-arctic bioclimate gradient, Alaska: synthesis of information from the ATLAS studies. Permafrost and Periglacial Processes. 14(2):103-123. PDF. doi:10.1002/ppp.452.
  • Walker, D.A., Kuss, H.P., Epstein, H.E., Kade, A.N., Vonlanthen, C., Raynolds, M.K., Daniëls, F.J.A. 2011. Vegetation of zonal patterned-ground ecosystems along the North American Arctic Transect. Applied Vegetation Science. 14:440-463. PDF
  • Walker, D.A., Lederer, N.D., Walker, M.D., Binnian, E., Everett, K.R., Nordstrand, E., Webber, P.J. 1989. Impacts of petroleum development in the Arctic: Response. Science. 245:764-765. PDF
  • Walker, D.A., Leibman, M.O., Epstein, H.E., Forbes, B.C., Bhatt, U.S., Raynolds, M.K., Comiso, J., Gubarkov, A.A., Khomutov, A.V., Jia, G.J., Kaarlejärvi, E., Kaplan, J.O., Kumpula, T., Kuss, H.P., Matyshak, G., Moskalenko, N.G., Orechov, P., Romanovsky, V.E., Ukraientseva, N.K., Yu, Q. 2009. Spatial and temporal patterns of greenness on the Yamal Peninsula, Russia: interactions of ecological and social factors affecting the Arctic normalized difference vegetation index. Environmental Research Letters. 4:16. PDF. doi:10.1088/1748-9326/4/4/045004.
  • Walker, D.A., Raynolds, M.K., Daniëls, F.J.A., Einarsson, E., Elvebakk, A., Gould, W.A., Katenin, A.E., Kholod, S.S., Markon, C.J., Melnikov, E.S., N.G., M., Talbot, S.S., Yurtsev, B.A., CAVM Team 2005. The Circumpolar Arctic Vegetation Map. Journal of Vegetation Science. 16(3):267-282. PDF. doi:10.1658/1100-9233(2005)016[0267:TCAVM]2.0.CO;2.
  • Walker, D.A., Raynolds, M.K., Gould, W.A. 2008. Fred Daniëls, Subzone A, and the North American Arctic Transect. Abhandlungen aus dem Westfälischen Museum für Naturkunde. 70:(3/4):387-400. PDF
  • Walker, D.A., Raynolds, M.K., Maier, H.A., Barbour, E.M., Neufeld, G.P. 2010. Circumpolar geobotanical mapping: a web-based plant-to-planet approach for vegetation-change analysis in the Arctic. Viten. 1:125-128. PDF
  • Walker, D.A., Talbot, S.S. 1997. Toward a new circumpolar arctic vegetation map. Arctic Research of the United States. 11:80-81.
  • Walker, D.A., Walker, M.D., Gould, W.A., Mercado, J., Auerbach, N.A., Maier, H.A., Neufeld, G.P. 2010. Maps for monitoring changes to vegetation structure and composition: The Toolik and Imnavait Creek grid plots. Viten. 1:121-123. PDF
  • Walker, D.A., Webber, P.J., Binnian, E.F., Everett, K.R., Lederer, N.D., Nordstrand, E.A., Walker, M.D. 1987. Cumulative Impacts of Oil Fields on Northern Alaskan Landscapes. Science. 238:(4828):757-761. PDF
  • Walker, D.A., Webber, P.J., Walker, M.D., Lederer, N.D., Meehan, R.H., Nordstrand, E.A. 1986. Use of geobotanical maps and automated mapping techniques to examine cumulative impacts in the Prudhoe Bay Oilfield, Alaska. Environmental Conservation. 13(2):149-160. PDF. doi:10.1017/S0376892900036754.
  • Webber, P.J., Walker, D.A. 1975. Vegetation and landscape analysis at Prudhoe Bay, Alaska: a vegetation map of the Tundra Biome study area. J. Brown (eds.) Ecological investigations of the Tundra Biome in the Prudhoe Bay region, Alaska. University of Alaska Fairbanks. Fairbanks, AK. pp. 81-91. PDF
  • Webber, P.J., Walker, D.A., Rowley, F. 1975. Gradient analysis of plant growth forms. J. Brown (eds.) Ecological and limnological reconnaissances from Prudhoe Bay into the Brooks Range, Alaska. pp. 31-35. PDF
  • van Bogaert, R., Walker, D.A., Jia, G.J., Grau, O., Hallinger, M., De Dapper, M., Jonasson, C. and Callaghan, T.V. 2007. Recent changes in vegetation. J. Richter-Menge, M.O. Jeffries and J.E. Overland (eds.) Arctic Report Card 2007. NOAA Arctic Research Program. PDF

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Talks and Posters

  • Auerbach, N.A., Walker, D.A. 1996. An electronic hierarchic geobotanical atlas for arctic system science. Purchase proceedings, presented at Second Circumpolar Arctic Vegetation Mapping Workshop and The CAVM-North American Workshop. Arendal, Norway, and Anchorage, AK, 19-24 May 1996/14-16 January 1997. Occasional Paper No. 52:26-27. PDF
  • Barbour, E.M., Walker, D.A., Maier, H.A., Balser, A.W., Grimes, J.P., Heinrichs, T.A., Nolan, M., Prokein, P., Pylant, C.L., Raynolds, M.K., Rogan, L.M., Sharpton, V.L., Stahlke, D.L., Vockeroth, S.G. 2006. Arctic Geobotanical Atlas. Arctic Science Conference, Arctic AAAS Division Meeting. Fairbanks, AK October 2-4. PDF
  • Gould, W.A., Raynolds, M.K., Walker, D.A., Edlund, S.A. 2001. Canadian Arctic vegetation and ecosystem properties. Fourth International Circumpolar Arctic Vegetation Mapping Workshop. Moscow, Russia April 10-13. PDF
  • Maier, H.A., Walker, D.A., Barbour, E.M., Balser, A.W., Grimes, J.P., Heinrichs, T.A., Nolan, M., Prokein, P., Pylant, C.L., Raynolds, M.K., Rogan, L.M., Sharpton, V.L., Stahlke, D.L., Vockeroth, S.G. 2006. Arctic Geobotanical Atlas. 26th Annual ESRI International User Conference. San Diego, CA August 7-12. PDF
  • Munger, C.A., Walker, D.A., Maier, H.A., Hamilton, T.D. 2008. Spatial analysis of glacial geology, surficial geomorphology, and vegetation in the Toolik Lake region: Relevance to past and future land-cover changes. Ninth International Conference on Permafrost. Fairbanks, AK June 29 - July 3. 2:1255-1260. PDF
  • Raynolds, M.K., Ananjeva, G.V., Drozdov, D.S., Daniëls, F.J.A., Einarsson, E., Elvebakk, A., Gould, W.A., Katenin, A.E., Kholod, S.S., Korostelev, Y.V., Maier, H.A., Markon, C.J., Moskalenko, N., Talbot, S.S., Walker, D.A. 2002. Second Draft of the Circumpolar Arctic Vegetation Map. ARCSS All-Hands Workshop. Seattle, WA February 20.
  • Raynolds, M.K., Walker, D.A., Gould, W.A., Markon, C.J. 2001. Synthesis of Alaska and Canada. Fourth International Circumpolar Arctic Vegetation Mapping Workshop. Moscow, Russia April 10-13. PDF
  • Walker, D.A. 2007. A Hierarchic Geobotanical Atlas. 41st Alaska Surveying and Mapping Conference. Fairbanks, AK 19-23 March. PDF
  • Walker, D.A. 2001. Circumpolar Arctic Vegetation Map: Plan for Synthesis. unknown. unknown . PDF
  • Walker, D.A. 2001. Welcome, history, progress, and future of the CAVM. Fourth International Circumpolar Arctic Vegetation Mapping Workshop. Moscow, Russia April 10-13. PDF
  • Walker, D.A. 1994. Information: Toward a new arctic vegetation map: St. Petersburg workshop. Arctic and Alpine Research. 27:103-104. PDF
  • Walker, D.A., Barbour, E.M., Maier, H.A. 2008. A Web-based Arctic Geobotanical Atlas and a New Hierarchy of Maps of the Toolik Lake Region, Alaska. Ninth International Conference on Permafrost. Fairbanks, AK, June 29 - July 3. 2:1893-1898. PDF
  • Walker, D.A., Burian, J.C., Epstein, H.E., Gould, W.A., Jia, G.J., Maier, H.A., Raynolds, M.K. 2001. Controls on Arctic NDVI Patterns: a Zonal Analysis. B22C-0176, presented at AGU Fall Meeting. San Francisco, CA, December 10-14. 82:B22C-0176.
  • Walker, D.A., Epstein, H.E., Kuss, P., Michaelson, G., Ping, C.L., Raynolds, M.K., Romanovsky, V.E., Tarnocai, C.T. 2004. Interactions of multiple factors for patterned-ground features across the Arctic bioclimate gradient. C12A-07, presented at AGU Fall Meeting. San Francisco, CA, December 13-17. 85:F424. PDF
  • Walker, D.A., Maier, H.A., Barbour, E.M., Balser, A.W., Grimes, J.P., Heinrichs, T.A., Nolan, M., Prokein, P., Pylant, C.L., Raynolds, M.K., Rogan, L.M., Sharpton, V.L., Stahlke, D.L., Vockeroth, S.G. 2007. Legacy IPY Hierarchic GIS Database for the Arctic Observatory at Toolik Lake. 41st Alaska Surveying and Mapping Conference. Westmark Hotel, Fairbanks, AK 19-23 March. PDF
  • Walker, D.A., Raynolds, M.K., Maier, H.A. 2003. The Circumpolar Arctic Vegetation Map: A tool for analysis of change in permafrost regions. C11E-05, presented at AGU Fall Meeting. San Francisco, CA, December 8 - 12. 84:C11E-05.
  • Walker, D.A., Raynolds, M.K., Maier, H.A., Barbour, E.M., Neufeld, G.P. 2010. Circumpolar geobotanical mapping: a web-based plant-to-planet approach for vegetation-change analysis in the Arctic. Mapping and Monitoring of Nordic Vegetation and Landscapes Conference. Hveragerði, Iceland 16-18 September. PDF
  • Walker, D.A., Raynolds, M.K., Maier, H.A., Murray, D.F., Markon, C.J., Talbot, S.S., Gould, W.A., Bliss, L.C., Edlund, S.A., Zoltai, S.C., Daniels, F.J.A., Wilhelm, M., Bay, C., Einarsson, E., Gundjonsson, G., Moskalenko, N.G., Ananjeva, G.V., Drozdov, D.S., Konchenko, L.A., Korostelev, Y.V., Melnikov, E., Ponomareva, O.E., Katenin, A.E., Kholod, S.S., Matveyeva, N.V., Safranova, I.N., Shelkunova, R., Yurtsev, B.A., Polezhaev, A.N., Elvebakk, A., Johansen, B.E., Trahan, N.G., Charron, T.M. 2002. Draft of the Circumpolar Arctic Vegetation Map. 53rd Alaska Science Conference of the American Association for the Advancement of Science Arctic Division. Fairbanks, AK September 18-21. PDF
  • Walker, D.A., Walker, M.D., Auerbach, N.A., Maier, H.A., Neufeld, G.P. 2009. Toolik Grid Plots: Baseline canopy height and species composition in 1990. Mapping and Monitoring of Nordic Vegetation and Landscapes. Hveragerdi, Iceland 16-18 September. PDF
  • Walker, D.A., Walker, M.D., Gould, W.A., Mercado, J., Auerbach, N.A., Maier, H.A., Neufeld, G.P. 2010. Maps for monitoring changes to vegetation structure and composition: The Toolik and Imnavait Creek grid plots. Mapping and Monitoring of Nordic Vegetation and Landscapes Conference. Hveragerði, Iceland 16-18 September. PDF

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Reports

  • Gonzalez, G., Gould, W.A., Raynolds, M.K. 2000. 1999 Canadian transect for the Circumpolar Arctic Vegetation Map. AGC Data Report. 89 pp.
  • Markon, C.J., Walker, D.A. 1999. Proceedings of the Third International Circumpolar Arctic Vegetation Mapping Workshop. USGS Open File Report No. 99-551. . 79. PDF
  • Munger, C.A., Raynolds, M.K., Kade, A.N., Walker, D.A. 2005. Biocomplexity of Patterned Ground: Mould Bay Expedition. AGC Data Report. 62 pp. PDF
  • Munger, C.A., Raynolds, M.K., Walker, D.A. 2004. July 2003 Banks Island Expedition: Vegetation, biomass, NDVI, soil, thaw layer, invertebrates, decomposition, biogeochemistry and turf-hummock studies. AGC Data Report. 72 pp. PDF
  • Raynolds, M.K., Markon, C.J. 2001. Fourth International Circumpolar Arctic Vegetation Mapping Workshop. US Geological Survey Open File Report 02-181. . 98. PDF
  • Walker, D.A., Lillie, A.C. 1996. Proceedings of the Second Circumpolar Arctic Vegetation Mapping Workshop and the CAVM-North American Workshop. Second Circumpolar Arctic Vegetation Mapping Workshop and The CAVM-North American Workshop. 52. PDF
  • Walker, D.A., Maier, H.A., Barbour, E.M., Raynolds, M.K. 2011. Final Report for A web-based multi-scale Arctic Geobotanical Atlas (AGA) for the Toolik Lake Field Station, Arctic Alaska, and the Circumpolar Region. AGC Final Report. 13 pp. PDF
  • Walker, D.A., Markon, C.J. 1996. Circumpolar arctic vegetation mapping workshop: abstracts and short papers. USGS Open File Report No. 96-251. . 121. PDF

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