CLIMATE SIGNAL IN THE RING WIDTH, DENSITY AND CARBON STABLE ISOTOPES IN PINE (PINUS SILVESTRIS L.) IN CENTRAL CAUCASUS

Enrico Brugnoli,Olga Solomina,Ekaterina Dolgova,Luciano Spaccino

doi:10.24057/2071-9388-2010-3-4-4-16

Abstract

Variability of width, maximum density and stable isotopes ( δ 13 C) in tree-rings of Scots pine (Pinus sylvestris L.) were studied in Northern Caucasus. Statistically sufficient agreements between ring width chronologies allow to construct composite chronology for the Elbrus area. Absence or low correlation between indices of the ring width and maximum density chronology point out different climatic signal. The influence of temperature and precipitation on these tree-ring parameters was also analyzed. The ring width of pine at the upper tree limit in the Baksan valley correlates positively with the June and July precipitation (r=0.3; 0.3; 0.4, p<0.05). No correlation with temperature parameters was found. The maximum density reflects the warm period temperature (April-October). The similarity in interannual variations of δ 13 C in annual rings between the individual samples means that their display a coherent common signal. This signal can be largely interpreted as the June and July precipitation.

Highlights

The longest continuous time series of meteorological observations in Caucasus slightly exceed a century
In this paper we report the results of the study of climatic signal in pine tree rings in Caucasus
To construct and analyze the ring width chronologies we used the standard procedures of measuring, cross-dating and indexation routinely used in tree-ring analysis [Stokes, 1968]

Summary

Introduction

The longest continuous time series of meteorological observations in Caucasus slightly exceed a century. In this paper we report the results of the study of climatic signal in pine tree rings in Caucasus. The tree-ring sites analyzed in this study are situated in the western and central part of the Greater Caucasus in Baksan and Teberda valleys at the elevation of 2200–2500 m asl. The western and central sectors of northern slope of the Greater Caucasus, where the study area is located, are in particular characterized by a strong convective activity in summer. Precipitation maxima occur in July–September in response to convective activity triggered by a combination of strong insolation and depressions developing on the Polar front and enhanced by the orographic uplift [Shahgedanova, 2002]

Methods

Results

Discussion

Conclusion