Oecologia

, Volume 162, Issue 2, pp 283–292

Patterns of Tamarix water use during a record drought

  • Jesse B. Nippert
  • James J. ButlerJr.
  • Gerard J. Kluitenberg
  • Donald O. Whittemore
  • Dave Arnold
  • Scott E. Spal
  • Joy K. Ward
Physiological Ecology - Original Paper

DOI: 10.1007/s00442-009-1455-1

Cite this article as:
Nippert, J.B., Butler, J.J., Kluitenberg, G.J. et al. Oecologia (2010) 162: 283. doi:10.1007/s00442-009-1455-1

Abstract

During a record drought (2006) in southwest Kansas, USA, we assessed groundwater dynamics in a shallow, unconfined aquifer, along with plant water sources and physiological responses of the invasive riparian shrub Tamarix ramosissima. In early May, diel water table fluctuations indicated evapotranspirative consumption of groundwater by vegetation. During the summer drought, the water table elevation dropped past the lowest position previously recorded. Concurrent with this drop, water table fluctuations abruptly diminished at all wells at which they had previously been observed despite increasing evapotranspirative demand. Following reductions in groundwater fluctuations, volumetric water content declined corresponding to the well-specific depths of the capillary fringe in early May, suggesting a switch from primary dependence on groundwater to vadose-zone water. In at least one well, the fluctuations appear to re-intensify in August, suggesting increased groundwater uptake by Tamarix or other non-senesced species from a deeper water table later in the growing season. Our data suggest that Tamarix can rapidly shift water sources in response to declines in the water table. The use of multiple water sources by Tamarix minimized leaf-level water stress during drought periods. This study illustrates the importance of the previous hydrologic conditions experienced by site vegetation for controlling root establishment at depth and demonstrates the utility of data from high-frequency hydrologic monitoring in the interpretation of plant water sources using isotopic methods.

Keywords

Diel water table fluctuationsEcohydrologyPhreatophyteStable isotopes

Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Jesse B. Nippert
    • 1
    • 2
    • 5
  • James J. ButlerJr.
    • 2
  • Gerard J. Kluitenberg
    • 3
  • Donald O. Whittemore
    • 2
  • Dave Arnold
    • 4
  • Scott E. Spal
    • 1
  • Joy K. Ward
    • 1
  1. 1.Department of Ecology and Evolutionary BiologyUniversity of KansasLawrenceUSA
  2. 2.Kansas Geological SurveyUniversity of KansasLawrenceUSA
  3. 3.Department of AgronomyKansas State UniversityManhattanUSA
  4. 4.Arnold RanchAshlandUSA
  5. 5.Division of BiologyKansas State UniversityManhattanUSA