Title: Allometry, nitrogen status, and carbon stable isotope composition of Pinus ponderosa seedlings in two growing media with contrasting nursery irrigation regimes
Author: Dumroese, R. Kasten; Page-Dumroese, Deborah S.; Brown, Robert E.;
Source: Canadian Journal of Forest Research. 41: 1091-1101.
Publication Series: Scientific Journal (JRNL)
Description: Nursery irrigation regimes that recharged container capacity when target volumetric water content reached 72%, 58%, and 44% (by volume) influenced Pinus ponderosa Douglas ex Lawson & C. Lawson growth more than either a 1:1 (by volume) Sphagnum peat - vermiculite (PV) or a 7:3 (by volume) Sphagnum peat - sawdust (PS) medium. Exponential fertilization avoided confounding irrigation and fertilization. Temporary nitrogen (N) immobilization in PS caused transient allometric differences prior to hardening. Subsequent release of immobilized N during the onset of hardening, when daily N flux decreased from 4.2% to 1.6%, allowed PS seedlings to avoid foliar N dilution experienced by PV seedlings. Media yielded seedlings with similar final morphological characteristics, although PS seedlings had improved N status. At onset, particle density and volumetric water content were similar for both media, but PS held about 10% more water than PV at all water potentials at experiment conclusion. Exposure to the driest water content (44%) decreased seedling growth and root N status compared with cohorts that were provided ample moisture (72%). Despite maximum tissue heterogeneity within samples and regardless of irrigation regime, seedlings became 1.3 more depleted of 13C as the growing season progressed. Refinement of sampling procedures, with focus on ontogenetics, may improve subsequent use of stable carbon isotopes in nursery research.
Keywords: allometry, nitrogen status, arbon stable isotope composition, Pinus ponderosa seedlings, nursery irrigation regimes
- 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
Dumroese, R. Kasten; Page-Dumroese, Deborah S.; Brown, Robert E. 2011. Allometry, nitrogen status, and carbon stable isotope composition of Pinus ponderosa seedlings in two growing media with contrasting nursery irrigation regimes. Canadian Journal of Forest Research. 41: 1091-1101.
Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility