Assessment of Response to Climate Change in Experiments with the Origins of Picea abies (L.) Karst. × P. obovata (Ledeb.) in the North Russian Plain

Abstract

The article studies the intraspecific response of European spruce (Picea abies (L.) Karst. × P. obovata (Ledeb.)) to climatic changes on the basis of data on the growth of 15 provenances in 31-year-old provenance plot of the North Russian Plain (Arkhangelsk and Vologda regions) simulating warming and cooling. We compared the actual height and diameter at the test site and the calculated height at the places of growth of the source stands, determined by recalculating the actual progeny growth data through the latitudinal growth coefficients proposed by I.V. Volosevich for the North Russian Plain. The difference between the calculated and actual growth rates of the corresponding provenance at the test site represented the response of the provenance to the change in growing conditions. The response was crosschecked with differences in climatic characteristics (sum of effective temperatures above 10 °C) and geographic coordinates of the places of origin and growth of spruce. Spruce has approximately the same response rate if offspring move by an equal amount of gradient (north latitude) to the south or to the north and if the climatic factor (sum of temperatures above 10 °C) changes towards warming or cooling. While the sum of temperatures changes above 10 °C for every 100 °C, the difference in growth in height and diameter will be 0.48 m and 0.42 cm, respectively; for each degree of change in northern latitude, on average, 0.50 m and 0.44 cm in height and diameter, respectively. However, for species from the northern taiga subzone, mainly represented by Siberian spruce (P. obovata) the response of the species will be half as much than for the origin of hybrid spruce (Picea abies (L.) Karst. × P. obovata (Ledeb.)) from the middle taiga subzone. The calculated values of response by height and diameter for European spruce should be considered when regulating seed transfer and used in forecasts for the adaptation of forestry measures to the expected climatic changes.