Study: Tree ring series of Bosnian pine (Pinus heldreichii Christ) from Pirin mountains in Bulgaria

Aim of this Study is to construct long and highly replicated tree ring chronology from the species, analyze the climate-growth relationships with available climate data and construct a proxy climate record with duration of 800 years or more.

Pirin Mountains are the second highest in Bulgaria (Vihren peak, 2917m a.s.l.). The climate in the range is formed under the complex influence of Mediterranean and Atlantic air masses, with the predominance of moist Mediterranean masses. This is reason for milder winters with frequent snowfalls and occasional Southwestern winds. Due to its specific climate Pirin Mountains have become refuge for numerous plant species, many of which are endemic. This is the reason why the majority of the northern part of the range has been declared a national park and included in UNESCOs Man and Biosphere list of very important natural zones. On the territory of the park are situated some of the best-preserved forests of the Balkan endemic species Pinus peuce and the very rare Pinus heldreichii.

Vihren peak (2917m a.s.l.) is situated in the central part of the mountains , just above Vihren and Bunderitsa hut. Its slopes are steep, often almost vertical (the North-Eastern wall is 400 meters high vertical wall). One very peculiar thing is that the base rock is marble. This is the reason for presence of many species that are capable of enduring both low temperatures and at the same time drought-type conditions. Many of them are very rare, included in the Bulgarian "Red Book" and are either Bulgarian, or Balkan endemic species. Of the tree species the most remarkable is Pinus heldreichii Christ. The slopes o Vihren are one of the "refuges" of the ancient forests, many of which consist of trees with age of 500+ years.

A magnificent old Pinus heldreichii (more than 700 years of age) along the Eastern slope of Vihren peak in Pirin, Bulgaria

Our team has been studying these forests for almost a decade. Up to now we have collected an impressive archive of tree ring series (more than 150 with age of +300 years), constructed several chronologies. We have presented results on conference meetings and prepared first articles (please, see a list below). Currently we are working in cooperation with the WSL team (dr. Valerie Trouet) for the analysis of the chronologies and continuation of the work. We also started a novel research on cambial activity (2010).

Collecting of the cores often is quite risky and requires the use of ropes and climbing equipment:)

Our "team" is coordinated by dr. Momchil Panayotov (Forestry University, Sofia, Bulgaria). During these years other people were attracted and took part in the collection of the cores, measurement and analysis. Among them are students Albena Ivanova, Yanitsa Todorova, Pepa Rangelova, Blagoy Stoyanov, Alexander Dountchev, Neli Nikolova and teachers in the University of Forestry Evgeni Tsavkov and Dr. Steffan Yurukov. Work has been supported by project 115/2008 of the University of Forestry, project 116/2010 of the University of Forestry and Project DTK 02/2/2010 of the National Science Fund

You can see some nice pictures from such work in our Galleries pages.


Panayotov, M., Bebi, P., Trouet, V., and Yurukov, S. (2010) Climate signal in tree-ring chronologies of Pinus peuce and Pinus heldreichii from the Pirin Mountains in Bulgaria. Trees - Structure and Function, 24: 479-490, 24: 479-490DOI: 10.1007/s00468-010-0416-y

Panayotov, M. and Yurukov, S. (2008) Pinus peuce and Pinus heldreichii tree rings as a key to past mountain climate in Southeastern Europe. Proceedings of TRACE2008 conference: 71-77, PDF file

Panayotov, M.P. and Yurukov, S. (2007) Tree ring chronology from Pinus peuce in Pirin Mts and the possibilities to use it for climate analysis. Phytologia Balcanica, 13(3): 313-320 , PDF file

Yurukov S.,Panayotov M., E.Tsavkov and P. Zhelev. (2005). Dendrological characteristic of Bosnian pine (Pinus heldreichii Christ) on karst terrains in Pirin National Park. Proceedings of the International Scientific Conference "Protected Karst Territories Conditions, Problems, Perspectives", 18-21. Oct. 2005, Shumen, Bulgaria.(PDF file, Bulgarian language, abstract in English. 0,5MB)


Dr. Momchil Panayotov, e-mail: mp2@ abv.bg (please note, there is one blank space after the "@" symbol, you have to remove it to send a mail. Nobody likes spam:)