ИСТИНА

The length of hydrological and meteorological instrumental observations in the Volga region (53-56N, 46-52E) is maximum 120 years, and for streamflow is even shorter and goes up to a maximum of 70 years.

The aim of the study is to determine a climatic signal in tree ring width (TRW) of the nine pine chronologies (Pinus Sylvestris) and to examine the relationships between the growth of the trees and the streamflow of Volga river’s inflowing streams and Palmer Drought Severity Index (PDSI).

Most of the pine chronologies demonstrate a response to the streamflow during the low-water season from May to September but don’t show any correlation during the flooding season from April to May.

Based on TRW data of the site Y01S we built a simple linear regression model and reconstruct streamflow of Ilet’ river for current July-September (JS) from 1827 to 2013. Correlation coefficient between TRW and the river streamflow is 0,55 (p<0,05). Therefore, the model explains 27% of JS streamflow variability (r2=0,27).

The strongest significant relationship between TRW and PDSI is shown in the regional master chronology MasterTY with correlation coefficient of 0,6 (p<0,05) for the period from July to September. Based on that finding we reconstruct PDSI for the period from 1828 to 2013.

The statistical characteristics of the model for PDSI reconstruction are more significant than for the streamflow reconstruction with explained variability of the streamflow data in the reconstruction of 34%. The study was supported by RFFI project № 16-35-00408.