The influence of temperature on latewood lignin content in treeline Norwayspruce compared with maximum density and ring width

The latewood lignin content, maximum density and total ring width of ten co nsecutive annual increments were determined in treeline Norway spruce (Pice a abies [L.] Karst.) using ultraviolet (UV) microscopy and radio-densitomet ry, respectively. A positive correlation between the total ring width and t he mean temperature of mid-July to August was identified, as was one betwee n the maximum density and the temperature of August-September. Lignin conte nt in the secondary cell wall layer of the terminal latewood tracheids was positively correlated with the temperature for the period running from the beginning of September until the third week of October. It can, therefore, be concluded that lignification of the cell wall is susceptible to the infl uence of climatic variability, as is the case with ring width and maximum d ensity.