Strip-Bark Morphology and Radial Growth Trends in Ancient Pinus sibirica Trees From Central Mongolia

• Published in: Carbohydrate Polymers
• Main Authors: Leland, Caroline, Cook, Edward R., Andreu-Hayles, Laia, Pederson, Neil, Hessl, Amy, Anchukaitis, Kevin J., Byambasuren, Oyunsanaa, Nachin, Baatarbileg, Davi, Nicole, D'Arrigo, Rosanne, Griffin, Kevin, Bishop, Daniel A., Rao, Mukund Palat
• Other Authors: Univ Arizona, Sch Geog & Dev
• Format: Article in Journal/Newspaper
• Language: English
• Published: AMER GEOPHYSICAL UNION 2018
• Subjects: cambial dieback; strip bark; dendroclimatology; standardization; Sibirica
• Online Access: http://hdl.handle.net/10150/627763; https://doi.org/10.1002/2017JG004196

Some of the oldest and most important trees used for dendroclimatic reconstructions develop strip-bark morphology, in which only a portion of the stem contains living tissue. Yet the ecophysiological factors initiating strip bark and the potential effect of cambial dieback on annual ring widths and tree-ring estimates of past climate remain poorly understood. Using a combination of field observations and tree-ring data, we investigate the causes and timing of cambial dieback events in Pinus sibirica strip-bark trees from central Mongolia and compare the radial growth rates and trends of strip-bark and whole-bark trees over the past 515years. Results indicate that strip bark is more common on the southern aspect of trees, and dieback events were most prevalent in the 19th century, a cold and dry period. Further, strip-bark and whole-bark trees have differing centennial trends, with strip-bark trees exhibiting notably large increases in ring widths at the beginning of the 20th century. We find a steeper positive trend in the strip-bark chronology relative to the whole-bark chronology when standardizing with age-dependent splines. We hypothesize that localized warming on the southern side of stems due to solar irradiance results in physiological damage and dieback and leads to increasing tree-ring increment along the living portion of strip-bark trees. Because the impact of cambial dieback on ring widths likely varies depending on species and site, we suggest conducting a comparison of strip-bark and whole-bark ring widths before statistically treating ring-width data for climate reconstructions. National Science Foundation [BCS-1210360, OPP-1737788] 6 month embargo; published online: 22 February 2018 This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [e-mail].