The results are given in the two reports from D. Zaharjevsky and A. Kirdjanov.
In the first part, D. Zaharjevsky summarized the state of the art in X-ray densitometry. In the second part he compared statistically three chronologies from different species (spruce, larch, pine) from Archangelsk ( 64°36'N/40°36'E) and compared them with climatological data from Archangelsk. The major scientific conclusion is that the maximum densities of all species show a clearer dependence on temperature data than all other parameters. The major influence occurs from May to August.
A. Kirdjanov studied five chronologies from the North of the Krasnoyarsk region and can be summarized as follows:
- Tree-ring width and maximum density chronologies obtained from Siberian larch (Larix sibirica, Ledeb) and Siberian spruce (Picea obovata, Ledeb) trees from 5 sites on the north of the Krasnoyarsk region (Russia) have been compared. The results of this analysis show that the statistical characteristics of variability of larch chronologies which resemble average values for each site are higher than those for spruce time series and increase for both species from site to site along the south-north gradient.
- The agreement analysis between index chronologies from different points has displayed that tree-ring width and maximum density chronologies contain different information about climate change.
- The correlation analysis of larch chronologies has shown that tree-ring width variability most closely connected with July temperature changes and maximum density of tree-rings reflects the temperature regime of a longer period than tree-ring width itself.
