- Plant physiological responses to episodic disturbance
- Stable isotope ecology
- Plant water relations and plant carbon balance
The work of my lab group revolves around studying how plants cope with environmental stress in desert ecosystems (including those in urban, riparian and upland areas). Specific questions we seek to answer include understanding 1) relationships between the physiology / morphology of stem succulents and their sensitivity to climate extremes, 2) patterns of plant resource allocation and how carbon allocation strategies (i.e. resource storage, growth, reproduction) govern the capacity for plants to cope with herbivory, drought and other stressors, 3) how local adaptation to environmental conditions impacts populations and species responses to climate change and other global change processes. To this end, we are applying stable isotope methods, dendrochronological techniques, measurements in plant water relations and measurements of plant carbon allocation and storage to improve our understanding of how desert plant systems function at multiple scales.
MAJOR THEMES AND PROJECTS:
- Local adaptation of a foundation species, Fremont cottonwood (Populus fremontii) to climate change and exotic species invasion. This project is in collaboration with researchers from Northern Arizona University with research locations in Arizona and Utah. Funded by the National Science Foundation, Macrosystems Biology program.
- Saltcedar (Tamarix spp) resource allocation strategies in response to stress caused by drought, salinity and episodic foliage herbivory. This project is in collaboration with researchers from UC Santa Barbara, the Desert Research Institute (Las Vegas, NV), and Northern Arizona University with field locations in Arizona and Nevada. Funded by the US Department of Agriculture, National Institute of Food and Agriculture. Go to http://rivrlab.msi.ucsb.edu/projects/TRC for more information.
- Vulnerability of columnar cacti to climate change as a function of stem functional morphology and physiology. This project is in collaboration with researchers from the University of Wyoming, the University of Arizona, Northern Arizona University, and Universidad Nacional Autónoma de Mexico (Hermosillo, Sonora), with research locations in Arizona, Sonora Mexico, Argentina and Chile.
- Climate change impacts on male and female individuals of dioecious tree species. This project is in collaboration with researchers from Northern Arizona University, the University of Utah and the US Geological Survey with field locations in Arizona and Utah.
Hultine KR, Majure LC, Nixon VS, Arias S, Búrquez A, Goettsch B, Puente-Martinez R, Zavala-Hurtado A. (2016). The role of botanical gardens in the conservation of Cactaceae. Bioscience. 66: 1057-1065
Hultine KR, Grady KC, Wood TE, Shuster SM, Stella JC, Whitham, TG. (2016). Climate change perils for dioecious plant species. Nature Plants. DOI 10.1038/NPLANTS.2016.109
Hultine KR, Williams DG, Dettman DL, Butterfield BJ, Puente-Martinez, R. (2016). Stable isotope physiology of stem succulents detects functional tradeoffs and bioclimatic specificity across a broad range of volume to surface area ratio. Oecologia. 182: 679-690
Hultine KR, Bean DW, Dudley TL, Gehring CA. (2015). Species introductions and their cascading impacts on biotic interactions in desert riparian ecosystems. Integrative and Comparative Biology 55: 587-601. Download Paper
Hultine KR, Dudley TL, Koepke DF, Bean DW, Glenn EP, Lambert AM. (2015). Patterns of herbivory-induced mortality of a dominant non-native tree/shrub (Tamarix spp.) in a southwestern US watershed. Biological Invasions 17: 1729-1742. Download Paper
Williams, D.G., K.R. Hultine and D.L. Dettman. 2014. Functional trade-offs in succulent stems predict responses to climate change in columnar cacti. Journal of Experimental Botany doi:10.1093/jxb/eru174. Download Paper
Hultine KR, Burtch KG, and Ehleringer JR. (2013) Gender specific patterns of carbon uptake and water use in a dominant riparian tree species exposed to a warming climate. Global Change Biology 19: 3390-3405. Download Paper
Hultine KR. Dudley TL. And Leavitt SW. (2013) Herbivory-induced mortality increases with radial growth in an invasive riparian phreatophyte. Annals of Botany 111: 1197-1206. Download Paper
Hultine KR, and Bush SE. (2011) Ecohydrological consequences of non-native riparian vegetation in the southwestern U.S.: a review from an ecophysiological perspective. Water Resources Research (in press). Download Paper
Hultine KR, Nagler PL, Morino K. Bush SE, Burtch, KG, Dennison PE, Glenn EP, and Ehleringer JR. (2010) Sap flux-scaled transpiration by tamarisk (Tamarix spp.) before, during and after episodic defoliation by the saltcedar leaf beetle (Diorhabda carinulata). Agricultural and Forest Meteorology 150: 1467-1475
Hultine KR, Belnap J, Dennison PE, Ehleringer JR, Lee ME, Nagler PL, Snyder KA, Uselman SM, van Riper III C, and West JB. (2010). Tamarisk biocontrol in the western United States: ecological and societal implications. Frontiers in Ecology and the Environment 8: 467-474. Download Paper
Hultine, KR, Bush, SE, and Ehleringer JR. (2010). Ecophysiology of riparian cottonwood and willow before, during and after two years of groundwater removal. Ecological Applications 20: 347-361. Download Paper
Hultine KR, Jackson TL, Burtch KG, Schaeffer SM, and Ehleringer JR (2008). Elevated stream inorganic nitrogen impacts on a dominant riparian tree species: results from an experimental riparian stream system. JGR Biogeosciences 113, G04025, DOI:10.1029/2008JG000809. Download Paper
Bush SE, Pataki DE, Hultine KR, West AG, Sperry JS and Ehleringer JR (2007) Wood anatomy constrains stomatal responses to atmospheric vapor pressure deficit in irrigated, urban trees. Oecologia 156, 13-20. Download Paper
Hultine KR, Bush SE, West AG and Ehleringer JR (2007) Population structure, physiology and ecohydrological impacts of dioecious riparian tree species of western North America. Oecologia 154, 85-93. Download Paper
West AG, Hultine KR, Jackson TL and Ehleringer JR (2007) Contrasting hydraulic strategies explain differential summer moisture use of Pinus edulis and Juniperus osteosperma. Tree Physiology 27, 1711-1720). Download Paper
Hultine KR, Koepke DF, Pockman WT, Fravolini A, Sperry JS, and Williams DG (2006) Influence of soil texture on hydraulic properties and water relations of a dominant warm-desert phreatophyte. Tree Physiology 26, 313-323. Download Paper
Fravolini A, Hultine KR, Brugnoli E, Gazal R, English N, and Williams DG (2005) Precipitation pulse use by an invasive woody legume: the role of soil texture and pulse size. Oecologia 144, 618-627. Download Paper
Huxman TE, Wilcox BP, Scott RL, Snyder KA, Breshears D, Small EE, Hultine KR, Pockman WT and Jackson RB (2005) Woody plant encroachment and the water cycle: an ecohydrological framework. Ecology 86, 308-319. Download Paper
Hultine KR, Scott RL, Cable WL and Williams DG (2004) Hydraulic redistribution by a dominant, warm-desert phreatophyte: seasonal patterns and response to precipitation pulses. Functional Ecology 18, 530-538. Download Paper
Hultine KR and Marshall JD (2000) Altitude trends in conifer leaf morphology and stable carbon isotope composition. Oecologia 123, 32-40. Download Paper