The Dendrochronological Signal of Pine Trees (Pinus Spp.) in Spain

Abstract

Thirty-one old-age pine stands in nine mountainous regions of Spain were studied in order to delineate dendrochronologically uniform areas. A country-wide cross-correlation analysis of the autoregressively standardized site chronologies showed the dendrochronological signal decreasing with distance so that beyond about 450 km crossdating becomes less reliable, but even over 630 km, the correlation coefficient is sometimes significantly high. A principal components analysis of the variance among the site chronologies segregated the chronologies into a northern and a southern group roughly along a line from Madrid to Barcelona. Two low-elevation northern sites were grouped with the southern sites. Moisture supply limits the growth of the pines in this group. In contrast, the high-elevation northern sites do not suffer from prolonged droughts. According to the uniform and extensive tree-ring signal in the south of the peninsula, the potential of dendrochronology for dating cultural objects is predicted to be favorable. Because of the greater variability between sites in the north, further studies are necessary to delineate uniform areas.