- Senior Global Futures Scientist, Julie Ann Wrigley Global Futures Laboratory
- Professor, School of Life Sciences, College of Liberal Arts and Sciences
- Affiliated Faculty, Center for Biodiversity Outcomes, Global Institute of Sustainability and Innovation
Tad Day is a plant ecologist who studies factors that control plant performance, plant litter decomposition and carbon cycling. While much of his past work investigated these questions in Antarctic tundra, the main aim of his present work is to unravel the mechanisms involved in plant litter decomposition in the Sonoran Desert. These mechanisms are poorly understood, limiting the ability of biogeochemists to accurately predict and model this important pathway of the carbon cycle in deserts.
While microbes appear to play a dominant role in litter decomposition in many ecosystems, direct breakdown of litter by sunlight (photodegradation) appears particularly important in deserts. Day's research examines how the optical, anatomical and chemical properties of leaf litter influence decomposition by environmental drivers such as sunlight, and biotic drivers such as microbes.
- PhD, Colorado State University, 1988
- MS, University of Idaho, 1985
- BS with distinction, Colorado State University, 1981
Guenon, R., T. A. Day, S. Velazco-Ayuso and R. Gros. 2017. Mixing of Aleppo pine and Holm oak litter increases biochemical diversity and alleviates N limitations of microbial activity. Soil Biology and Biochemistry 105(Feb):216-226. DOI: 10.1016/j.soilbio.2016.11.023. (link )
Day, T. A., R. Guénon and C. T. Ruhland. 2015. Photodegradation of plant litter in the Sonoran Desert varies by litter type and age. Soil Biology and Biochemistry 89(Oct):109-122. DOI: 10.1016/j.soilbio.2015.06.029. (link )
Elmendorf, S. C., G. H. Henry, R. D. Hollister, R. G. Björk, A. D. Bjorkman, T. V. Callaghan, L. Siegwart Collier, E. J. Cooper, J. H. Cornelissen, T. A. Day, A. Fosaa, W. A. Gould, J. Grétarsdóttir, J. Harte, L. Hermanutz, D. S. Hik, A. Hofgaard, F. Jarrad, I. Svala Jónsdóttir, F. Keuper, K. Klanderud, J. A. Klein, S. Koh, G. Kudo, S. I. Lang, V. Loewen, J. L. May, J. Mercado, A. Michelsen, U. Molau, I. H. Myers-Smith, S. F. Oberbauer, S. Pieper, E. Post, C. Rixen, C. H. Robinson, N. Martin Schmidt, G. R. Shaver, A. Stenström, A. Tolvanen, O. Totland, T. G. Troxler, C. Wahren, P. J. Webber, J. M. Welker and P. A. Wookey. 2012. Global assessment of experimental climate warming on tundra vegetation: Heterogeneity over space and time. Ecology Letters 15(2):164-175. DOI: 10.1111/j.1461-0248.2011.01716.x. (link )
Elmendorf, S. C., G. H. Henry, R. D. Hollister, R. G. Björk, N. Boulanger-Lapointe, E. J. Cooper, J. H. Cornelissen, T. A. Day, E. Dorrepaal, T. G. Elumeeva, M. Gill, W. A. Gould, J. Harte, D. S. Hik, A. Hofgaard, D. R. Johnson, J. F. Johnstone, I. Svala Jónsdóttir, J. C. Jorgenson, K. Klanderud, J. A. Klein, S. Koh, G. Kudo, M. Lara, E. Levesque, B. Magnusson, J. L. May, J. A. Mercado-Di'az, A. Michelsen, U. Molau, I. H. Myers-Smith, S. F. Oberbauer, V. G. Onipchenko, C. Rixen, N. Martin Schmidt, G. R. Shaver, M. J. Spasojevic, T. E. Thórhallsdóttir, A. Tolvanen, T. G. Troxler, C. E. Tweedle, S. Villareal, C. Wahren, X. Walker, P. J. Webber, J. M. Welker and S. Wipf. 2012. Plot-scale evidence of tundra vegetation change and links to recent summer warming. Nature Climate Change 2:453-457. DOI: 10.1038/nclimate1465. (link )
Strauss, S. L., F. Garcia-Pichel and T. A. Day. 2012. Soil microbial carbon and nitrogen transformations at a glacial foreland on Anvers Island, Antarctic Peninsula. Polar Biology 35(10):1459-1471. DOI: 10.1007/s00300-012-1184-5. (link )
Strauss, S. L., T. A. Day and F. Garcia-Pichel. 2011. Nitrogen cycling in desert biological soil crusts across biogeographic regions in the southwestern United States. Biogeochemistry 108(1):171-182. DOI: 10.1007/s10533-011-9587-x. (link )
Day, T. A., C. T. Ruhland, S. L. Strauss, J. Park, M. L. Krieg, M. A. Krna and D. M. Bryant. 2009. Response of plants and the dominant microarthropod, Cryptopygus antarcticus, to warming and contrasting precipitation regimes in Antarctic tundra. Global Change Biology 15(7):1640-1651. DOI: 10.1111/j.1365-2486.2009.01919.x. (link )
Krna, M. A., T. A. Day and C. T. Ruhland. 2009. Effects of neighboring plants on the growth and reproduction of Deschampsia antarctica in Antarctic tundra. Polar Biology 32:1487-1494. DOI: 10.1007/s00300-009-0646-x. (link )
Strauss, S. L., C. T. Ruhland and T. A. Day. 2009. Trends in soil characteristics along a recently deglaciated foreland on Anvers Island, Antarctic Peninsula. Polar Biology 32:1779-1788. DOI: 10.1007/s00300-009-0677-3. (link )
Day, T. A., C. T. Ruhland and F. Xiong. 2008. Warming increases aboveground biomass and C stocks in vascular-plant dominated Antarctic tundra. Global Change Biology 14(8):1827-1843. DOI: 10.1111/j.1365-2486.2008.01623.x. (link )
Day, T. A., E. T. Zhang and C. T. Ruhland. 2007. Exposure to solar UV-B radiation accelerates mass and lignin loss of Larrea tridentata litter in the Sonoran Desert. Plant Ecology 193:185-194. DOI: 10.1007/s11258-006-9257-6. (link )
Mueller, E. C. and T. A. Day. 2005. The effect of urban ground cover on microclimate, growth and leaf gas exchange of oleander in Phoenix, Arizona. International Journal of Biometeorology 49(4):244-255. DOI: 10.1007/s00484-004-0235-1. (link )
Day, T. A., P. Gober, F. Xiong and E. A. Wentz. 2002. Temporal patterns in near-surface CO2 concentrations over contrasting vegetation types in the Phoenix metropolitan area. Agricultural and Forest Meteorology 110(3):229-245. DOI: 10.1016/S0168-1923(01)00288-X. (link )
Wentz, E. A., P. Gober, R. C. Balling Jr and T. A. Day. 2002. Spatial patterns and determinants of winter atmospheric carbon dioxide concentratinos in an urban environment. Annals of the Association of American Geographers 92(1):15-28. DOI: 10.1111/1467-8306.00277. (link )
Grobe, T. A., C. T. Ruhland and T. A. Day. 1997. A new population of Colobanthus quitensis at Arthur Harbor, Antarctica: correlating recruitment with warmer temperatures.. Arctic and Alpine Research
McGraw, J. B. and T. A. Day. 1997. Size and characterization of a natural seed bank in Antarctica.. Arctic and Alpine Research
Day, T. A. and S. M. Demchik. 1996. Influence of enhanced UV-B radiation on biomass allocation and pigment concentrations in Brassica rapa. Vegetatio 109-116.
Day, T. A., B. W. Howells and C. T. Ruhland. 1996. Changes in growth and pigment concentrations with leaf age in pea under modulated UV-B field treatments.. Plant, Cell and Environmental 101-108.
Day, T. A. and J. B. McGraw. 1996. Ozone depletion, UV-B radiation and performance of Antarctic vascular plants. Antarctic Journal of the United States
Demchik, S. M. and T. A. Day. 1996. Effect of enhance UV-B radiation on pollen quantity, quality and seed yield in Brassica rapa.. American Journal of Botany 573-579.
Day, G. N., N. Cressie, S. S. Carroll and T. R. Carroll. 1995. Spatial modeling of snow water equivalent using airborne and ground-based data.. Environmetrics 127-139.
Day, T. A. and T. C. Vogelmann. 1995. Alterations in photosynthesis and pigment distributions in leaves following UV-B exposure.. Physiologia Plantarum 443-440.
Day, T. A. and T. C. Vogelmann. 1995. Alterations in photosynthesis and pigment distributions in pea leaves following UV-B exposure.. Physiologia Plantarum 433-440.
Day, T. A. and J. K. Detling. 1994. Water relations of Agropyron smithii and Bouteloua gracilis and community evapotranspiration following long-term grazing by prarie dogs.. American Midland Naturalist 381-392.
Day, T. A. 1993. Relating ultraviolet-B screening effectiveness of foliage to absorbing-compound concentration and anatomical characteristics in a diverse group of plants.. Oecologia 542-550.
Day, T. A. and J. K. Detling. 1990. Grassland patch dynamics and herbivore grazing preference following urine deposition. Ecology 180-188.
Martin, C. A., T. A. Day, J. M. Briggs, J. C. Stutz and M. R. Sommerfeld. 2001. Primary productivity at the CAP LTER. Poster presented at the January 19, 2001, CAP LTER Third Annual Poster Symposium, Center for Environmental Studies, Arizona State University, Tempe AZ. (link )
Mueller, E. C. and T. A. Day. 2000. Effects of urban ground cover on microclimate and landscape plant performance. Poster presented at 19 January 2000, CAP LTER Second Annual Poster Symposium, Center for Environmental Studies, Arizona State University, Tempe, AZ.
Vining, E. C., J. B. Gallaher and T. A. Day. 1999. Effects of urban ground cover on microclimate and landscape plant performance. Poster presented at the 22 January 1999, CAP LTER First Annual Poster Symposium, Center for Environmental Studies, Arizona State University, Tempe.