Title: Missing and dark rings associated with drought in Pinus halepensis
Author: Novak, Klemen; De Luis, Martin; Gricar, Jozica; Prislan, Peter; Merela, Maks; Smith, Kevin T.; Cufar, Katarina.;
Source: IAWA Journal. 37: 260-274.
Publication Series: Scientific Journal (JRNL)
Description: The responses of the vascular cambium and tracheid differentiation to extreme drought in Aleppo pine (Pinus halepensis Mill.) were investigated. The research focused on the drought year of 2005, in the primary study area at Maigmo (MAI) in southeastern Spain, with comparisons in Jarafuel (JAL) and Guardamar (GUA). The climate in this region is typically warm and dry with hot summers. Wood formation throughout the 2005 growing season was studied in transverse microtome sections and integrated with a retrospective dendrochronological analysis of crossdated increment cores collected in 2009. For most anatomical sections collected throughout the growing season at MAI, the vascular cambium appeared to be dormant as indicated by the low number of cells per radial file. Occasionally, immature xylem derivatives were observed during the growing season but without production of an annual ring. In increment cores collected at MAI, the 2005 position in the annual ring series contained either a narrow ring of both earlywood and latewood (47% of samples), a narrow ring of apparent latewood with no earlywood (13%), or a missing ring (50%). We introduce the term "dark ring" to refer to those annual rings of apparent latewood with no earlywood. For trees at JAL, the 2005 ring had below-average width and contained both earlywood and latewood. At GUA, the trees produced the widest 2005 ring of all three sites and mainly contained an intra-annual density fluctuation (IADF). The IADF was formed after cambial reactivation in the autumn. Although dark rings, IADFs, and especially missing rings complicate dendrochronological analysis, these anatomical features may provide an additional proxy record from which to infer climate variability and change in the past.
Keywords: Aleppo pine, wood formation, missing ring, dark ring, false ring, intra-annual density fluctuation, Spain
- 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.
- This publication may be available in hard copy. Check the Northern Research Station web site to request a printed copy of this publication.
- Our on-line publications are scanned and captured using Adobe Acrobat. During the capture process some typographical errors may occur. Please contact Sharon Hobrla, email@example.com if you notice any errors which make this publication unusable.
XML: View XML
Novak, Klemen; De Luis, Martin; Gricar, Jozica; Prislan, Peter; Merela, Maks; Smith, Kevin T.; Cufar, Katarina. 2016. Missing and dark rings associated with drought in Pinus halepensis. IAWA Journal. 37: 260-274.
Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility