ENVIRONMENTAL RECONSTRUCTION FROM TREE RINGS OF ARCHAEOLOGICAL TIMBERS IN THE ALTAI MOUNTAINS, RUSSIA

Global reconstruction of climate change based on high-resolution multiproxy climate records is limited by geographical distribution of sites, especially for periods before AD 1000. Tree rings from living trees and subfossil wood were actively employed in climate reconstruction in the mountains of central Eurasia. There is the first attempt to estimate dendroclimatic potential of archaeological timbers from South Siberia. The goal of this study was to evaluate the climatic signal in tree rings from archaeological timbers of various ages and cultures in the Altai Mountains, Russia. We studied tree-ring widths of archaeological timbers from Siberian Scythians tombs (400-200 BC), Huns-Sarmatian burial mounds (AD 200-400) and Turks stone enclosures (AD 600-800) in high and low elevations of southeastern Altai. We crossdated tree rings and built 6 floating chronologies of larch (Larix sibirica). The 1574 years of the discontinuous chronologies spanned radiocarbon ages 325 BC to AD 650. Statistical properties and periodicity of tree-ring width variability of archaeological time series were compared with tree-ring series of living trees from the same region. A strong summer temperature signal was found in the Scythian tree rings from tombs at high elevation (2050-2345 m asl). The Scythian tree-ring chronology might be used as a master chronology of southeastern the Altai Mountains for crossdating and a as climatic proxy. The tree-ring variability of the Turks chronology (1600 m asl) showed insect outbreaks signal. Tree rings of Huns-Sarmatian wood (1600 m asl) are complacent and can not be used for an environmental reconstruction. The dendrochronological analysis indicates that the wood used for burial purpose was cut in surroundings forested sites. The most suitable wood for climatic reconstruction is from archaeological sites located at and above upper tree line. The study suggests that archaeological wood has a great potential for developing long-term climatic proxies from tree rings in the Altai Mountains.