Scots pine tree ring structure modifications and relation with climate

Abstract

In this study we assessed the tree ring structure modifications and the relation with climate in Scots pine from Aleșd region (Romania). Tree rings structures were analysed based on microscopic sections obtained from the core sample. The analysis on the area of the incomplete lignified cells (IC) and the lignified cells (CL) was made. The results show a high frequency of false rings, and unlignified cells. The tree ring with the highest unlignified cells part could be observed in the years 2007 and 1989. A reduced number of the unlignified cells were formed in the year 1998. An anomaly was analyzed in the tree ring structure of the year 1986. The temperature below 10 °C in the second period of the growing season has stopped the process of lignification of the wood cell walls. This study confirms the influence of temperature on the formation of the Scots pine tree rings. Key words: Scots pine, anatomical structure, radial growth, tree rings, temperature.