Title: The dynamic pipeline: hydraulic capacitance and xylem hydraulic safety in four tall conifer species
Author: McCulloh, Katherine A.; Johnson, Daniel M.; Meinzer, Frederick C.; Woodruff, David R.;
Source: Plant, Cell & Environment. 37(5): 1171-1183.
Publication Series: Scientific Journal (JRNL)
Description: Recent work has suggested that plants differ in their relative reliance on structural avoidance of embolism versus maintenance of the xylem water column through dynamic traits such as capacitance, but we still know little about how and why species differ along this continuum. It is even less clear how or if different parts of a plant vary along this spectrum. Here we examined how traits such as hydraulic conductivity or conductance, xylem vulnerability curves, and capacitance differ in trunks, large- and small-diameter branches, and foliated shoots of four species of co-occurring conifers. We found striking similarities among species in most traits, but large differences among plant parts. Vulnerability to embolism was high in shoots, low in small- and large-diameter branches, and high again in the trunks. Safety margins, defined as the pressure causing 50% loss of hydraulic conductivity or conductance minus the midday water potential, were large in small-diameter branches, small in trunks and negative in shoots. Sapwood capacitance increased with stem diameter, and was correlated with stem vulnerability, wood density and latewood proportion. Capacitive release of water is a dynamic aspect of plant hydraulics that is integral to maintenance of long-distance water transport.
Keywords: capacitance, conifers, hydraulic conductance, safety margins, vulnerability curves
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
XML: View XML
McCulloh, Katherine A.; Johnson, Daniel M.; Meinzer, Frederick C.; Woodruff, David R. 2013. The dynamic pipeline: hydraulic capacitance and xylem hydraulic safety in four tall conifer species. Plant, Cell & Environment. 37(5): 1171-1183.
Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility